---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Thu 09/06/12: 29 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:54 AM - Re: Stromberg NA-S3A1 (gboothe5@comcast.net) 2. 05:18 AM - Re: Stromberg NA-S3A1 (Ben Charvet) 3. 05:44 AM - Re: Stromberg NA-S3A1 (Jerry Dotson) 4. 06:08 AM - Stromberg NA-S3A1 (Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]) 5. 06:17 AM - Re: Stromberg NA-S3A1 (tools) 6. 06:22 AM - Re: Stromberg NA-S3A1 (gboothe5@comcast.net) 7. 06:51 AM - Re: Stromberg NA-S3A1 (SENTUCHOWS@aol.com) 8. 07:37 AM - Re: Stromberg NA-S3A1 (tools) 9. 07:37 AM - Re: Stromberg NA-S3A1 (Gerry Holland) 10. 07:54 AM - Re: Re: Stromberg NA-S3A1 (SENTUCHOWS@aol.com) 11. 08:25 AM - Re: Stromberg NA-S3A1 (tools) 12. 08:29 AM - Re: a way to avoid routing spars (C N Campbell) 13. 08:32 AM - Re: Stromberg NA-S3A1 (dgaldrich) 14. 08:38 AM - Re: Stromberg NA-S3A1 (Don Emch) 15. 08:48 AM - Re: what I would do differently, wing spars and other things (kevinpurtee) 16. 08:55 AM - Re: Re: Stromberg NA-S3A1 (gboothe5@comcast.net) 17. 09:00 AM - Re: Re: Stromberg NA-S3A1 (SENTUCHOWS@aol.com) 18. 09:08 AM - Re: Stromberg NA-S3A1 (Andrew Eldredge) 19. 09:18 AM - Fly Baby page (SENTUCHOWS@aol.com) 20. 10:11 AM - Re: Re: Stromberg NA-S3A1 (Ryan Mueller) 21. 10:39 AM - Re: Stromberg NA-S3A1 (Don Emch) 22. 11:03 AM - a little flying, a little turning around (Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]) 23. 12:02 PM - Re: Spar Routing (curtdm(at)gmail.com) 24. 05:12 PM - Re: a little flying, a little turning around (aerocarjake) 25. 05:58 PM - Re: Stromberg NA-S3A1 (taildrags) 26. 06:04 PM - Re: a little flying, a little turning around (taildrags) 27. 08:25 PM - Re: Re: Stromberg NA-S3A1 (Andrew Eldredge) 28. 08:58 PM - Re: Stromberg NA-S3A1 (tools) 29. 10:10 PM - Re: Stromberg NA-S3A1 (taildrags) ________________________________ Message 1 _____________________________________ Time: 02:54:35 AM PST US Subject: Re: Pietenpol-List: Stromberg NA-S3A1 From: gboothe5@comcast.net Thanks, Gerry. I can stop chasing ghosts! ------Original Message------ From: Gerry Holland Sender: owner-pietenpol-list-server@matronics.com ReplyTo: pietenpol-list@matronics.com Subject: Re: Pietenpol-List: Stromberg NA-S3A1 Sent: Sep 5, 2012 10:37 PM Gary...Yes it stumbles. Occasionally it even stops after a landing run. I blocked a runway two weeks ago! Tools method of using 'Carb Hot Air' is one I haven't tried so that is worth knowing. Mine is also reported as 'popping' when descending over Strip throttled back with Carb Hot Air on. Other than that, it's a real old A75! Gerry Sent on the Sprint Now Network from my BlackBerry ________________________________ Message 2 _____________________________________ Time: 05:18:31 AM PST US From: Ben Charvet Subject: Re: Pietenpol-List: Stromberg NA-S3A1 After a few stumbles like that you get used to advancing the throttle slowly. You don't want to disconcert the masses (or your passengers) Ben Charvet NX866BC A-65 On 9/5/2012 9:58 PM, Gary Boothe wrote: > > I'm sure there are several of you that fly, or have flown, with this > carb. I am wondering if it is characteristic for it to stumble if the > throttle is advanced too quickly. > > Gary Boothe > > NX308MB > > * > > > * -- Ben Charvet, PharmD Staff Pharmacist Parrish Medical center ________________________________ Message 3 _____________________________________ Time: 05:44:11 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "Jerry Dotson" Gary I am running a Marvel Ma-3A with no pump and it will stumble if you open the throttle to quick. It is worse just starting to taxi seems like. Not a deal for me. A cold start is a little problematic. Can't seem to get how much prime is right. -------- Jerry Dotson 59 Daniel Johnson Rd Baker, FL 32531 First flight June 16,2012 Started building July, 2009 21" wheels Lycoming O-235 C2C Jay Anderson CloudCars prop 76 X 44 do not archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382492#382492 ________________________________ Message 4 _____________________________________ Time: 06:08:55 AM PST US From: "Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]" Subject: Pietenpol-List: Stromberg NA-S3A1 Gary, I have no accelerator pump on my NA-S3A1 and it does not stumble unless it is cooler weather (55F or colder) and I haven't warmed up the engine thoroughly. (of course your engine and induction system are completely different than my A-65 setup) If I advance the throttle smoothly on takeoff or in flight after some slow flight the engine never stumbles. (thankfully) Mike C. ________________________________ Message 5 _____________________________________ Time: 06:17:36 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "tools" Here's another tidbit I just learned. Apparently aircraft carbs run very rich at full idle, to help with cooling (since the prop is so slow, not nearly as much cooling there). If you open the throttle just a tad, it gets it off the idle circuit, where it's more like a regular carb. Sure enough, when it's hot and I'm flying young eagles in a Glastar, on the rollout the engine gets VERY rough and is on the verge of quitting. I advance the throttle just a bit and get it off idle circuit and that helps a ton. Also, when trying to hot start, I'll keep it off the idle circuit to avoid or lessen the effects of flooding. Hand propping is a different matter. I'd NEVER try that while hand propping alone. I haven't flown the piet enough repetitively on a hot day like that to be a problem. I have found that it's easier to flood on hot days and I go through the standard a65 unflood routine, and it starts first flip afterwards. Because of the success there, I haven't tried hand propping with someone else in the cockpit with the carb off the idle circuit. Now, how this affects cold starting and prime is... EVERY time I've had the engine catch and run a few revolutions, I can't get it started easily after that point. Well, it's just like pulling it through, and with the engine on the extra rich idle circuit, it floods. Now, every time it catches a few revs and quits, I just turn the mags off, open the throt and pull it backwards a dozen pulls, reset everything and viola, easy start 1st pull after that. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382495#382495 ________________________________ Message 6 _____________________________________ Time: 06:22:29 AM PST US Subject: Re: Pietenpol-List: Stromberg NA-S3A1 From: gboothe5@comcast.net Thanks, Mike! There was some talk on the Piper Super Cub list about slightly enrichening the mixture to help ease the problem. You may already be there. Gary ------Original Message------ From: Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC] Sender: owner-pietenpol-list-server@matronics.com ReplyTo: pietenpol-list@matronics.com Subject: Pietenpol-List: Stromberg NA-S3A1 Sent: Sep 6, 2012 6:07 AM Gary, I have no accelerator pump on my NA-S3A1 and it does not stumble unless it is cooler weather (55F or colder) and I haven't warmed up the engine thoroughly. (of course your engine and induction system are completely different than my A-65 setup) If I advance the throttle smoothly on takeoff or in flight after some slow flight the engine never stumbles. (thankfully) Mike C. Sent on the Sprint Now Network from my BlackBerry ________________________________ Message 7 _____________________________________ Time: 06:51:53 AM PST US From: SENTUCHOWS@aol.com Subject: Re: Pietenpol-List: Stromberg NA-S3A1 The Stromberg carb is a good one. It shouldn't stumble if adjusted properly. Please read Harry Fenton's Advice on the Flybaby site. I just reb uilt an A-65 and the stromberg carb that is on it. and It doesn't stumble. Dave In a message dated 9/6/2012 9:22:41 A.M. Eastern Daylight Time, gboothe5@comcast.net writes: --> Pietenpol-List message posted by: gboothe5@comcast.net Thanks, Mike! There was some talk on the Piper Super Cub list about slightly enrichening the mixture to help ease the problem. You may already be there. Gary ------Original Message------ From: Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC] Sender: owner-pietenpol-list-server@matronics.com ReplyTo: pietenpol-list@matronics.com Subject: Pietenpol-List: Stromberg NA-S3A1 Sent: Sep 6, 2012 6:07 AM --> Pietenpol-List message posted by: "Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]" Gary, I have no accelerator pump on my NA-S3A1 and it does not stumble unless it is cooler weather (55F or colder) and I haven't warmed up the engine thoroughly. (of course your engine and induction system are completely different than my A-65 setup) If I advance the throttle smoothly on takeoff or in flight after some slow flight the engine never stumbles. (thankfully) Mike C. Sent on the Sprint=AE Now Network from my BlackBerry=AE ________________________________ Message 8 _____________________________________ Time: 07:37:34 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "tools" Dick bought my carb at Sun-n-fun and just sent it out for a complete rebuild. And in it's defense, it NEVER stumbled on me (except for the broke primer line) except while adding power to taxi IMMEDIATELY after startup. However, I was warned (by quite a few people) that just firewalling it with no regard wasn't a good idea, and knowing it has no accelator pump, it made sense. I started the carb heat routine while I was troubleshooting the backfiring (lean condition) caused by the broke primer line, and it helped quite a bit, which lets me know it would help with a lean condition caused by quick acceleration and no accelerator pump. Also, it didn't make sense to waste time taking my hand off the throttle, moving to the carb heat (all while slowing down and wasting runway), then back to the throttle to go around. So it's a routine I use ALL the time. While a good carb, it is old... I'm going to go read the article you mention. I do have a question for you and Mike. Can you get your carbs to hesitate? If it's adjusted properly, will it hesitate at all? Under any normal condition? I guess the whole point is this. If SOME hesitation under an extremely quick advance of the throttle from a full idle is normal, then you can experience it knowing things are probably alright with your carb. As how these things go, I was warned of it and after I JUST became a little comfortable with it, I did advance the throttle more quickly (I would advance the throttle VERY slowly at first because I wasn't much used to a taildragger, rather than trying to overcome a difficulty with the carb) and found that hesitation so assumed it normal. As it turned out, it wasn't! A technique I use with jet engines is to never let the engine "go to sleep". Especially with pure jets (no fan) and older jets, the response time from a developed idle can be dangerously slow. If you jockey the engines just enough, you'll keep them in a position where you have good response, without adding any significant thrust that would compromise the approach. Same applies to a piet. I notice many light civil pilots basically fly a no power final approach (which guarantees making the field with an engine failure, not a bad idea). Now if you fly that approach at a close to touchdown speed, if you do get low and add power with hesitation, you're in bad shape. If you fly that approach at a higher speed, short of touchdown and glide into it, you have margin for error, enough time (speed) to get through a hesitation. I, on the other hand, with a huge lack of experience in light civil planes, and YEARS AND YEARS of "bad habits", fly a lower power on approach, which keeps my engine out of the region where it would hesitate with a quick advance anyway. As I mentioned, the whole point of the discussion (in my mind) is to help us understand what the limitations of our carbs are so that we can determine if something isn't right. It's quite possible it SHOULDN'T ever hesitate and my flying habits would mask that condition and I'd never know if my carb was adjusted right in that regime or not. Lastly, the old drip from these old carbs. I'm on the verge of buying a little Chief with an A65. The owner just had the carb totally overhauled (to the tune of $600) because it would drip. I was told that was silly, because they all drip... I'm of the opinion that no good carb should just drip. Something is wrong in there if it does. May not really matter because it won't drip while running, but still... Oh ya, one more thing. When I was buying n2rn it was being inspected. A cylinder had to be pulled for some work. After we put it together and ran it, it had a little pop on acceleration. Dick wasn't happy and we thought maybe leaking a little air somewhere and we went about tightening all the hose clamps on the intake system. Problem went away. None of them seemed loose. It does seem that this engine is quite sensitive to any leaks in the intake system. So don't confuse that problem with a POSSIBLE propensity for hesitating due to a lack of complexity. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382499#382499 ________________________________ Message 9 _____________________________________ Time: 07:37:34 AM PST US Subject: Re: Pietenpol-List: Stromberg NA-S3A1 From: Gerry Holland I agree that the Stromberg is a good Carb. and widely used but there are some 'stumblers' out there including mine. One of the FAA Notices I came across whilst investing this was Continental Engines M64-6. You might all know of it? I've attached it for information. I am going to try it towards winter time. As for the stumbling....going tinker about but open throttle carefully until I feel happy about it. Gerry ________________________________ Message 10 ____________________________________ Time: 07:54:19 AM PST US From: SENTUCHOWS@aol.com Subject: Re: Pietenpol-List: Re: Stromberg NA-S3A1 Dick, One of the major problems with older Stromberg is the fit between the carb and the throttle shaft. As this area becomes warn, outside air leaks in around the shaft. You have a lean condition that cannot be adjusted out. . Lean on idle means hesitation and engine stoppage. Just my experience. Dave In a message dated 9/6/2012 10:39:49 A.M. Eastern Daylight Time, n0kkj@yahoo.com writes: --> Pietenpol-List message posted by: "tools" Dick bought my carb at Sun-n-fun and just sent it out for a complete rebuild. And in it's defense, it NEVER stumbled on me (except for the broke primer line) except while adding power to taxi IMMEDIATELY after startup. However, I was warned (by quite a few people) that just firewalling it with no regard wasn't a good idea, and knowing it has no accelator pump, it made sense. I started the carb heat routine while I was troubleshooting the backfiring (lean condition) caused by the broke primer line, and it helped quite a bit, which lets me know it would help with a lean condition caused by quick acceleration and no accelerator pump. Also, it didn't make sense to waste time taking my hand off the throttle, moving to the carb heat (all while slowing down and wasting runway), then back to the throttle to go around. So it's a routine I use ALL the time. While a good carb, it is old... I'm going to go read the article you mention. I do have a question for you and Mike. Can you get your carbs to hesitate? If it's adjusted properly, will it hesitate at all? Under any normal condition? I guess the whole point is this. If SOME hesitation under an extremely quick advance of the throttle from a full idle is normal, then you can experience it knowing things are probably alright with your carb. As how these things go, I was warned of it and after I JUST became a little comfortable with it, I did advance the throttle more quickly (I would advance the throttle VERY slowly at first because I wasn't much used to a taildragger, rather than trying to overcome a difficulty with the carb) and found that hesitation so assumed it normal. As it turned out, it wasn't! A technique I use with jet engines is to never let the engine "go to sleep". Especially with pure jets (no fan) and older jets, the response time from a developed idle can be dangerously slow. If you jockey the engines just enough, you'll keep them in a position where you have good response, without adding any significant thrust that would compromise the approach. Same applies to a piet. I notice many light civil pilots basically fly a no power final approach (which guarantees making the field with an engine failure, not a bad idea). Now if you fly that approach at a close to touchdown speed, if you do get low and add power with hesitation, you're in bad shape. If you fly that approach at a higher speed, short of touchdown and glide into it, you have margin for error, enough time (speed) to get through a hesitation. I, on the other hand, with a huge lack of experience in light civil planes, and YEARS AND YEARS of "bad habits", fly a lower power on approach, which keeps my engine out of the region where it would hesitate with a quick advance anyway. As I mentioned, the whole point of the discussion (in my mind) is to help us understand what the limitations of our carbs are so that we can determine if something isn't right. It's quite possible it SHOULDN'T ever hesitate and my flying habits would mask that condition and I'd never know if my carb was adjusted right in that regime or not. Lastly, the old drip from these old carbs. I'm on the verge of buying a little Chief with an A65. The owner just had the carb totally overhauled (to the tune of $600) because it would drip. I was told that was silly, because they all drip... I'm of the opinion that no good carb should just drip. Something is wrong in there if it does. May not really matter because it won't drip while running, but still... Oh ya, one more thing. When I was buying n2rn it was being inspected. A cylinder had to be pulled for some work. After we put it together and ran it, it had a little pop on acceleration. Dick wasn't happy and we thought maybe leaking a little air somewhere and we went about tightening all the hose clamps on the intake system. Problem went away. None of them seemed loose. It does seem that this engine is quite sensitive to any leaks in the intake system. So don't confuse that problem with a POSSIBLE propensity for hesitating due to a lack of complexity. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382499#382499 ________________________________ Message 11 ____________________________________ Time: 08:25:20 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "tools" The carb in n2rn was totally overhauled to the tune of $600 also, by a well respected aviation carb shop (got all the receipts). I assume (though I havn't pulled and checked) that the throttle shaft issue would be resolved if worn for that sort of rebuild and yellow tagging. Also, it would never quit while idling and starts well, both indicating that it isn't a worn throttle shaft. I've had problems with worn throttle shafts on tractors (very similar carbs) and old skid steers with Wisconsin VH4D's. That bulletin aforementioned is really interesting! Also hadn't yet found the incredible wealth of info on the fly baby website about little airplane engines. Super useful info. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382503#382503 ________________________________ Message 12 ____________________________________ Time: 08:29:59 AM PST US From: "C N Campbell" Subject: Re: Pietenpol-List: a way to avoid routing spars My chart from Bruhn's " Analysis and Design of Airplane Structures" shows spruce at 15% moisture content at 27 Pounds per cubic foot. Of course, this book was printed in 1949 -- figures might be different now. Chuck ----- Original Message ----- From: Clif Dawson To: pietenpol-list@matronics.com Sent: Thursday, September 06, 2012 2:19 AM Subject: Re: Pietenpol-List: a way to avoid routing spars Uh, Jack, I think you'll find that to be 31 lb at 12% moisture content. At least according to the US Forest Products Lab. The closest you're going to get to that is Western Red Cedar with a corresponding reduction in strength. Clif Calculate it. Sitka Spruce has a density of 21.86 lbs/ft3. Jack Phillips NX899JP Smith Mountain Lake, Virginia ------------------------------------------------------------------------- --- ________________________________ Message 13 ____________________________________ Time: 08:32:10 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "dgaldrich" Ref the drip on Stromberg carbs, there was a guy at OSH who seems to know EVERYTHING about the Stromberg and showed us a mod right from the NAS3 overhaul manual that permanently fixes the leak. It involves plugging a port that ends up below float level when a tail wheel aircraft is on the ground and drilling a small hole "higher" up on the carb body. Easy to do and a permanent fix or so he said. What he warned about was the typical "Must be the float cover gasket. I'll just lean on the screws and tighten it a bit more." response from many mechanics. That does nothing useful if the gasket is correctly installed and can warp the cover if done to an extreme. Same guy said he was close to FAA-PMA approval for replacement float needle and seats. That would be a good thing since the steel ones are pretty much NLA. As an unrelated data point, my Piper Cherokee has an FAA warning on the instrument panel about not rapidly advancing the throttle even though the O-320 uses a Marvel Dribbler MA4-SPA with an accelerator pump. Dave Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382505#382505 ________________________________ Message 14 ____________________________________ Time: 08:38:03 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "Don Emch" I get a stumble sometimes in the 1000-1200 rpm range. I think it may have something to do with the transition from the idle jet to the main jet. I've experienced this on other carbs too. Don Emch NX899DE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382507#382507 ________________________________ Message 15 ____________________________________ Time: 08:48:54 AM PST US Subject: Pietenpol-List: Re: what I would do differently, wing spars and other things From: "kevinpurtee" So Oscar, you know that despite the fact that I'm recovering I can still kick your butt, right?:) Just kidding, of course. On the rebuild, we will do the following: - 3 piece wing, - Use a Gary Boothe fuel tank (~16 gallons), - Move the fuel tank filler port forward a little for ease of refueling, - Probably use the lightweight fabric as Jack mentioned, - Slant the back seat back a little as Jack mentioned, - Figure out a way to make Shelley more comfortable in the front seat, raise the seat, figure out better cushions, whatever, - Maybe raise the turtle deck an inch? We'll see, - Use fittings at the top of the rear cabanes as an attach point for the front seat shoulder harness attach cable vs. the through-the-cabane eyebolts we used, - Maybe use a head rest to raise the back seat shoulder harness, - I loved the brakes, but need to figure out a way to quit popping spokes. May just use Jack's design. We'll see, - Maybe a cutout in the wing? - Add a sump to the fuel tank, of course.... I loved the airplane and it performed nicely. These are changes for convenience (except for the sump in the fuel tank, of course...). -------- Kevin "Axel" Purtee NX899KP Austin/San Marcos, TX Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382508#382508 ________________________________ Message 16 ____________________________________ Time: 08:55:01 AM PST US Subject: Re: Pietenpol-List: Re: Stromberg NA-S3A1 From: gboothe5@comcast.net Exactly where I'm getting it! ------Original Message------ From: Don Emch Sender: owner-pietenpol-list-server@matronics.com ReplyTo: pietenpol-list@matronics.com Subject: Pietenpol-List: Re: Stromberg NA-S3A1 Sent: Sep 6, 2012 8:37 AM I get a stumble sometimes in the 1000-1200 rpm range. I think it may have something to do with the transition from the idle jet to the main jet. I've experienced this on other carbs too. Don Emch NX899DE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382507#382507 Sent on the Sprint Now Network from my BlackBerry ________________________________ Message 17 ____________________________________ Time: 09:00:14 AM PST US From: SENTUCHOWS@aol.com Subject: Re: Pietenpol-List: Re: Stromberg NA-S3A1 NoKK. try this, _http://www.bowersflybaby.com/tech/fenton.htm#nologs_ (http://www.bowersflybaby.com/tech/fenton.htm#nologs) In a message dated 9/6/2012 11:25:34 A.M. Eastern Daylight Time, n0kkj@yahoo.com writes: --> Pietenpol-List message posted by: "tools" The carb in n2rn was totally overhauled to the tune of $600 also, by a well respected aviation carb shop (got all the receipts). I assume (though I havn't pulled and checked) that the throttle shaft issue would be resolved if worn for that sort of rebuild and yellow tagging. Also, it would never quit while idling and starts well, both indicating that it isn't a worn throttle shaft. I've had problems with worn throttle shafts on tractors (very similar carbs) and old skid steers with Wisconsin VH4D's. That bulletin aforementioned is really interesting! Also hadn't yet found the incredible wealth of info on the fly baby website about little airplane engines. Super useful info. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382503#382503 ________________________________ Message 18 ____________________________________ Time: 09:08:26 AM PST US Subject: Re: Pietenpol-List: Stromberg NA-S3A1 From: Andrew Eldredge My stromberb stumbles when advanced quickly. The stumble was a contributing factor to 7229R's appearance in the NTSB database. In my "oral counseling" with the FAA, we talked about not bein so quick on the throttle. ________________________________ Message 19 ____________________________________ Time: 09:18:17 AM PST US From: SENTUCHOWS@aol.com Subject: Pietenpol-List: Fly Baby page Here is the addy for the bowers fly baby site. There is a lot of info on engines and wood working. You can learn from this site. Dave _http://www.bowersflybaby.com/tech/index.html#woodi_ (http://www.bowersflybaby.com/tech/index.html#woodi) ________________________________ Message 20 ____________________________________ Time: 10:11:43 AM PST US Subject: Re: Pietenpol-List: Re: Stromberg NA-S3A1 From: Ryan Mueller Strombergs are excellent carbs, simple tech that has been proven over many years on god knows how many different production/experimental aircraft and engines. As Dave mentioned, the dripping is a simple issue of where the float bowl vent port is relative to the level of fuel in the bowl when the carburetor is installed on a taildragger. This was addressed over 50 years ago by a Service Bulletin.....shops/people don't know about or don't perform the SB, and they still drip....from D&G Supply's page: "For Stromberg/NAS model carburetors utilized on "taildraggers", care must be taken to control the fuel level in the bowl to accommodate the slanted mounting of this unit on the engine to prevent overflow leakage. There is a modification to this carburetor per Service Bulletin #73 dated 6/58 that removes a potential leaking air bleed hole located low in the throat by plugging and re-drilling a new one further up". Simple resolution. I just happened to stumble upon the gentleman Dave mentioned in the Vintage Barn (Bob Kachergius), and sat in on his talk.....he definitely knows what he's talking about. He went through the carb top to bottom, with samples, cutaway carbs, etc, pointing out all the different little details of an overhaul that might get missed: SB 73, the warping from overtightening the screws, looking for evidence of corrosion from water at in the bottom of the float bowl, how the float needle seat hole many times was not drilled deep enough at the factory, so the seat is too proud and you can't properly set the float level unless you machine it properly, etc etc, and how he addresses them. His overhaul price was a little more than some other shops, but I'd be hard pressed to imagine you could find a more thorough overhaul. Steve Krog interviewed him for an article in the August 2011 VAA mag, and he's apparently written numerous articles in various type club publications (Cub Club, etc). Anywho, he's got an ad up on Barnstormers: http://www.barnstormers.com/classified_392052_STROMBERG+NA-S3++CARBURETORS.html Ryan ryan@rmueller.org On Thu, Sep 6, 2012 at 9:37 AM, tools wrote: > > Dick bought my carb at Sun-n-fun and just sent it out for a complete > rebuild. And in it's defense, it NEVER stumbled on me (except for the > broke primer line) except while adding power to taxi IMMEDIATELY after > startup. > > However, I was warned (by quite a few people) that just firewalling it > with no regard wasn't a good idea, and knowing it has no accelator pump, it > made sense. I started the carb heat routine while I was troubleshooting > the backfiring (lean condition) caused by the broke primer line, and it > helped quite a bit, which lets me know it would help with a lean condition > caused by quick acceleration and no accelerator pump. > > Also, it didn't make sense to waste time taking my hand off the throttle, > moving to the carb heat (all while slowing down and wasting runway), then > back to the throttle to go around. So it's a routine I use ALL the time. > > While a good carb, it is old... I'm going to go read the article you > mention. I do have a question for you and Mike. Can you get your carbs to > hesitate? If it's adjusted properly, will it hesitate at all? Under any > normal condition? > > I guess the whole point is this. If SOME hesitation under an extremely > quick advance of the throttle from a full idle is normal, then you can > experience it knowing things are probably alright with your carb. > > As how these things go, I was warned of it and after I JUST became a > little comfortable with it, I did advance the throttle more quickly (I > would advance the throttle VERY slowly at first because I wasn't much used > to a taildragger, rather than trying to overcome a difficulty with the > carb) and found that hesitation so assumed it normal. As it turned out, it > wasn't! > > A technique I use with jet engines is to never let the engine "go to > sleep". Especially with pure jets (no fan) and older jets, the response > time from a developed idle can be dangerously slow. If you jockey the > engines just enough, you'll keep them in a position where you have good > response, without adding any significant thrust that would compromise the > approach. Same applies to a piet. > > I notice many light civil pilots basically fly a no power final approach > (which guarantees making the field with an engine failure, not a bad idea). > Now if you fly that approach at a close to touchdown speed, if you do get > low and add power with hesitation, you're in bad shape. If you fly that > approach at a higher speed, short of touchdown and glide into it, you have > margin for error, enough time (speed) to get through a hesitation. > > I, on the other hand, with a huge lack of experience in light civil > planes, and YEARS AND YEARS of "bad habits", fly a lower power on approach, > which keeps my engine out of the region where it would hesitate with a > quick advance anyway. > > As I mentioned, the whole point of the discussion (in my mind) is to help > us understand what the limitations of our carbs are so that we can > determine if something isn't right. It's quite possible it SHOULDN'T ever > hesitate and my flying habits would mask that condition and I'd never know > if my carb was adjusted right in that regime or not. > > Lastly, the old drip from these old carbs. I'm on the verge of buying a > little Chief with an A65. The owner just had the carb totally overhauled > (to the tune of $600) because it would drip. I was told that was silly, > because they all drip... > > I'm of the opinion that no good carb should just drip. Something is wrong > in there if it does. May not really matter because it won't drip while > running, but still... > > Oh ya, one more thing. When I was buying n2rn it was being inspected. A > cylinder had to be pulled for some work. After we put it together and ran > it, it had a little pop on acceleration. Dick wasn't happy and we thought > maybe leaking a little air somewhere and we went about tightening all the > hose clamps on the intake system. Problem went away. None of them seemed > loose. It does seem that this engine is quite sensitive to any leaks in > the intake system. So don't confuse that problem with a POSSIBLE > propensity for hesitating due to a lack of complexity. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=382499#382499 > > ________________________________ Message 21 ____________________________________ Time: 10:39:30 AM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "Don Emch" Dave and Gary, I had the old hole plugged and new drilled in mine at overhaul. Supposed to be better for sitting in the 3 point at a steeper angle like mine does. Never leaks. As far as the stumble goes... it is very faint and since I've noticed it in so many other airplanes, I've never given it much thought. Don Emch NX899DE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382516#382516 ________________________________ Message 22 ____________________________________ Time: 11:03:15 AM PST US From: "Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]" Subject: Pietenpol-List: a little flying, a little turning around Out for fuel at nearby Medina Airport over Labor Day weekend and as I appro ached that veil of rainshowers was moving in towards my destination. I made a 180 degree turn and headed to home base since if I would have land ed the showers would have moved in and trapped me there. A good excuse to go fly another day. After I got back I was just a bit cool so laid down on the pavement by the hangar under the nose of the plane to feel the heat absorbed by the blacktop. See the fun things you'll get to do when you finish your Pietenpol or to th e newest planes in the air owner/operators? Fun stuff. Mike C. do not archive ________________________________ Message 23 ____________________________________ Time: 12:02:05 PM PST US Subject: Pietenpol-List: Re: Spar Routing From: "curtdm(at)gmail.com" Thanks Jack. That's exactly what I was looking for. I noticed the question sparked another thread. One must keep to the plans to keep the Top Curmudgeon pro tem at bay. "Fellows, this is a dangerous road to begin walking down. OK, I resisted replying to Mikie's post, but this is going on too long, too far..........May I remind you that y'all are in jeopardy of being disqualified on being able to call your ship a "Pietenpol". There are no Pietenpol plans (that I know of) that mention anything but routed spars from solid spruce. Sorry, but don't kill the messenger................... Since the Top Curmudgeon has taken a leave of absence from this list, I fear that there will be no one to herd the masses in the right direction. That is why I feel compelled to mention this. " Dan Helsper -------- Curt Merdan Flower Mound, TX Do Not Archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382520#382520 ________________________________ Message 24 ____________________________________ Time: 05:12:14 PM PST US Subject: Pietenpol-List: Re: a little flying, a little turning around From: "aerocarjake" nice....!! I like the thought of soaking up the heat form the asphalt, although the sun never shines here in Seattle so the asphalt can't absorb it... (ha!) do not archive -------- Jake Schultz - curator, Newport Way Air Museum (OK, it's just my home) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382554#382554 ________________________________ Message 25 ____________________________________ Time: 05:58:36 PM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "taildrags" Ah, my favorite old carb! I've worked with probably a half-dozen different ones now, and the one that is presently on Scout (A75) behaves precisely as Tools describes. So I do what Tools does... when I get ready to take off, I apply carb heat and leave it on till the engine is running strong and we're ready to unstick from the runway (just a couple of seconds, really). I have not tried the trick of easing in just a little throttle to get it off the idle circuit first, but that's another one I'll try. A quick shove on the throttle, hot or cold, without carb heat applied is a guarantee of stumble, hesitation, and hard swallowing on my part. As to the dribble, I've ended that problem by carefully setting the float level per the information that is also found on the FlyBaby site. It's a bit tedious but if done slowly and carefully and with the simple little measuring tool, it will be correct and you won't get dribble out the air box. I also don't fly auto gas... the Stromberg on my old A65 would drool fuel every time I tried auto gas if I set the float level for avgas, so I stopped flying with car gas. -------- Oscar Zuniga Medford/Ashland, OR Air Camper NX41CC "Scout" A75 power Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382560#382560 ________________________________ Message 26 ____________________________________ Time: 06:04:38 PM PST US Subject: Pietenpol-List: Re: a little flying, a little turning around From: "taildrags" Mikee- I can relate, in more ways than one. Down near my former home field of San Geronimo (TX), a popular destination for quickie outings is Medina Lake, maybe 20 miles west of the field. I have taken off many times headed for a lazy sightseeing/keeping the skies safe patrol over the lake, only to find as I made my way over, that a line of thunder-bumpers and rain dumpers was coming into view. Discretion being the better part of valor, I set the autopilot to execute a coordinated 180 turn back to the field (ha!)- with worries about erosion from flying through rain going through my head. I must say though, I've never plopped down under the airplane to soak up the warmth of the pavement. That just wasn't necessary in Texas. Now up here in Oregon, probably so! do not archive -------- Oscar Zuniga Medford/Ashland, OR Air Camper NX41CC "Scout" A75 power Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382561#382561 ________________________________ Message 27 ____________________________________ Time: 08:25:45 PM PST US Subject: Re: Pietenpol-List: Re: Stromberg NA-S3A1 From: Andrew Eldredge Tools said: "Now, how this affects cold starting and prime is... EVERY time I've had the engine catch and run a few revolutions, I can't get it started easily after that point. Well, it's just like pulling it through, and with the engine on the extra rich idle circuit, it floods. Now, every time it catches a few revs and quits, I just turn the mags off, open the throt and pull it backwards a dozen pulls, reset everything and viola, easy start 1st pull after that." I've had this expeirence several times, last time was labor day attempting a hot start, but I did not know this procedure. To be clear, is this the "flood clearing" procecure? Usually on a hot start, I'll not bother "priming" with any pulls before the mags go on, the compression is tight and it will usually fire up on the first turn, but from time to time, "that" will happen, and I don't have a better solution than to shut off the fuel and wait a while. Andrew Eldredge Provo, UT On Thu, Sep 6, 2012 at 11:11 AM, Ryan Mueller wrote: > Strombergs are excellent carbs, simple tech that has been proven over many > years on god knows how many different production/experimental aircraft and > engines. > > As Dave mentioned, the dripping is a simple issue of where the float bowl > vent port is relative to the level of fuel in the bowl when the carburetor > is installed on a taildragger. This was addressed over 50 years ago by a > Service Bulletin.....shops/people don't know about or don't perform the SB, > and they still drip....from D&G Supply's page: "For Stromberg/NAS model > carburetors utilized on "taildraggers", care must be taken to control the > fuel level in the bowl to accommodate the slanted mounting of this unit on > the engine to prevent overflow leakage. There is a modification to this > carburetor per Service Bulletin #73 dated 6/58 that removes a potential > leaking air bleed hole located low in the throat by plugging and > re-drilling a new one further up". Simple resolution. > > I just happened to stumble upon the gentleman Dave mentioned in the > Vintage Barn (Bob Kachergius), and sat in on his talk.....he definitely > knows what he's talking about. He went through the carb top to bottom, with > samples, cutaway carbs, etc, pointing out all the different little details > of an overhaul that might get missed: SB 73, the warping from > overtightening the screws, looking for evidence of corrosion from water at > in the bottom of the float bowl, how the float needle seat hole many times > was not drilled deep enough at the factory, so the seat is too proud and > you can't properly set the float level unless you machine it properly, etc > etc, and how he addresses them. > > His overhaul price was a little more than some other shops, but I'd be > hard pressed to imagine you could find a more thorough overhaul. Steve Krog > interviewed him for an article in the August 2011 VAA mag, and he's > apparently written numerous articles in various type club publications (Cub > Club, etc). Anywho, he's got an ad up on Barnstormers: > > > http://www.barnstormers.com/classified_392052_STROMBERG+NA-S3++CARBURETORS.html > > Ryan > ryan@rmueller.org > > > On Thu, Sep 6, 2012 at 9:37 AM, tools wrote: > >> >> Dick bought my carb at Sun-n-fun and just sent it out for a complete >> rebuild. And in it's defense, it NEVER stumbled on me (except for the >> broke primer line) except while adding power to taxi IMMEDIATELY after >> startup. >> >> However, I was warned (by quite a few people) that just firewalling it >> with no regard wasn't a good idea, and knowing it has no accelator pump, it >> made sense. I started the carb heat routine while I was troubleshooting >> the backfiring (lean condition) caused by the broke primer line, and it >> helped quite a bit, which lets me know it would help with a lean condition >> caused by quick acceleration and no accelerator pump. >> >> Also, it didn't make sense to waste time taking my hand off the throttle, >> moving to the carb heat (all while slowing down and wasting runway), then >> back to the throttle to go around. So it's a routine I use ALL the time. >> >> While a good carb, it is old... I'm going to go read the article you >> mention. I do have a question for you and Mike. Can you get your carbs to >> hesitate? If it's adjusted properly, will it hesitate at all? Under any >> normal condition? >> >> I guess the whole point is this. If SOME hesitation under an extremely >> quick advance of the throttle from a full idle is normal, then you can >> experience it knowing things are probably alright with your carb. >> >> As how these things go, I was warned of it and after I JUST became a >> little comfortable with it, I did advance the throttle more quickly (I >> would advance the throttle VERY slowly at first because I wasn't much used >> to a taildragger, rather than trying to overcome a difficulty with the >> carb) and found that hesitation so assumed it normal. As it turned out, it >> wasn't! >> >> A technique I use with jet engines is to never let the engine "go to >> sleep". Especially with pure jets (no fan) and older jets, the response >> time from a developed idle can be dangerously slow. If you jockey the >> engines just enough, you'll keep them in a position where you have good >> response, without adding any significant thrust that would compromise the >> approach. Same applies to a piet. >> >> I notice many light civil pilots basically fly a no power final approach >> (which guarantees making the field with an engine failure, not a bad idea). >> Now if you fly that approach at a close to touchdown speed, if you do get >> low and add power with hesitation, you're in bad shape. If you fly that >> approach at a higher speed, short of touchdown and glide into it, you have >> margin for error, enough time (speed) to get through a hesitation. >> >> I, on the other hand, with a huge lack of experience in light civil >> planes, and YEARS AND YEARS of "bad habits", fly a lower power on approach, >> which keeps my engine out of the region where it would hesitate with a >> quick advance anyway. >> >> As I mentioned, the whole point of the discussion (in my mind) is to help >> us understand what the limitations of our carbs are so that we can >> determine if something isn't right. It's quite possible it SHOULDN'T ever >> hesitate and my flying habits would mask that condition and I'd never know >> if my carb was adjusted right in that regime or not. >> >> Lastly, the old drip from these old carbs. I'm on the verge of buying a >> little Chief with an A65. The owner just had the carb totally overhauled >> (to the tune of $600) because it would drip. I was told that was silly, >> because they all drip... >> >> I'm of the opinion that no good carb should just drip. Something is >> wrong in there if it does. May not really matter because it won't drip >> while running, but still... >> >> Oh ya, one more thing. When I was buying n2rn it was being inspected. A >> cylinder had to be pulled for some work. After we put it together and ran >> it, it had a little pop on acceleration. Dick wasn't happy and we thought >> maybe leaking a little air somewhere and we went about tightening all the >> hose clamps on the intake system. Problem went away. None of them seemed >> loose. It does seem that this engine is quite sensitive to any leaks in >> the intake system. So don't confuse that problem with a POSSIBLE >> propensity for hesitating due to a lack of complexity. >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=382499#382499 >> >> >> >> >> >> >> >> ========== >> st" target="_blank">http://www.matronics.com/Navigator?Pietenpol-List >> ========== >> http://forums.matronics.com >> ========== >> le, List Admin. >> ="_blank">http://www.matronics.com/contribution >> ========== >> >> >> >> > * > > * > > ________________________________ Message 28 ____________________________________ Time: 08:58:52 PM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "tools" Yep, classic a65 flood clearing procedure from what I've heard from a few different sources. Mags - off Throt - wide open Blades - pull through BACKWARDS, about a dozen Throt - closed (EASY to screw this up, be VERY careful) Carb heat - off Mags - on Start as usual. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382569#382569 ________________________________ Message 29 ____________________________________ Time: 10:10:53 PM PST US Subject: Pietenpol-List: Re: Stromberg NA-S3A1 From: "taildrags" Andrew; my experience with the Stromberg when it floods is EXACTLY the same as Tools'... but when I smell gas and the engine isn't starting I turn the fuel 'off', open the throttle wide, then slowly and patiently pull the prop through BACKWARDS a blade at a time, maybe 10-12 blades. What you're trying to do is evaporate excess fuel that's in the combustion chambers so don't hurry pulling those blades through. When you think that the excess fuel is all gone, turn the fuel valve back on and crack the throttle and try propping it normally again. BRAKES SET OR WHEELS CHOCKED! It can happen that the engine will fire with excess fuel available in the intake tubes, which means that it will catch and accelerate, and you need to be ready for that eventuality. It'll settle down quickly. If it starts, it will be normal. If it doesn't (and this happened to me many times in hot weather with the engine hot), repeat the above procedure and don't be in a hurry. In fact, I had almost as good results as the above by just shutting off the fuel, opening the throttle wide, and going back into the hangar or FBO to do other stuff for awhile until I thought the excess fuel had evaporated and I had another chance to fire up the engine. Cessna drivers wondered what the heck I was doing ;o) I have never flooded the 75, for some reason. It seems to want more fuel on starting than the 65 did, but then again they run two different Strombergs and we all know that Strombergs are like women: you have to treat them right and treat them like individuals, and they will reward you if you do that. My 65 had a temperamental (starting) but utterly reliable (running) brunette Stromberg; my 75 has a quick-starting but cold-natured redhead Stromberg. Heaven help us if I ever have an engine with a hot-blooded and wild blonde Stromberg! Oh, and if it has a mixture control-! Look out, Marilyn Monroe! Marvel-Scheblers are more like men, I guess... all alike in the basics, and always ready for action if stroked a time or two since stroking shoots some fuel in there to get the juices flowing every time. I can't tell you how many times I have stroked the throttle on Scout out of habit and inattention on starting, then realized that it does absolutely nothing for the Stromberg to open and close the butterfly in the venturi in that carb if no air is flowing through it. -------- Oscar Zuniga Medford/Ashland, OR Air Camper NX41CC "Scout" A75 power Read this topic online here: http://forums.matronics.com/viewtopic.php?p=382572#382572 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message pietenpol-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Pietenpol-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/pietenpol-list Browse Digests http://www.matronics.com/digest/pietenpol-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.