AeroElectric-List Digest Archive

Sun 09/23/12


Total Messages Posted: 17



Today's Message Index:
----------------------
 
     1. 01:34 AM - Re: ACF-50 Anti-corrosion between block and alternator mount... (B Tomm)
     2. 06:41 AM - Re: Why did this AMP crimp on connection get singed and fail? (Bill Watson)
     3. 07:07 AM - Re: Misprint in Z-16, v.12/ OV with Rotax generators? (Ken)
     4. 09:44 AM - Re: ACF-50 Anti-corrosion between block and alternator mount... (Michael Burbidge)
     5. 10:03 AM - Start Solenoid Orientation (Jeff Luckey)
     6. 10:31 AM - Re: ACF-50 Anti-corrosion between block and alternator mount... (Robert L. Nuckolls, III)
     7. 10:41 AM - Re: What crimper to use for B&C alternator field terminals... (Robert L. Nuckolls, III)
     8. 11:00 AM - Re: Why did this AMP crimp on connection get singed and fail? (Robert L. Nuckolls, III)
     9. 11:09 AM - Re: pitot tube (Robert L. Nuckolls, III)
    10. 11:10 AM - Re: Re: Pitot tube slightly plugged... (Robert L. Nuckolls, III)
    11. 11:13 AM - Re: ACF-50 Anti-corrosion between block and alternator mount... (Robert L. Nuckolls, III)
    12. 01:31 PM - Re: Start Solenoid Orientation (Robert L. Nuckolls, III)
    13. 01:38 PM - Re: Misprint in Z-16, v.12/ OV with Rotax generators? (Robert L. Nuckolls, III)
    14. 02:47 PM - Yesterday's Project - Show & Tell (Jeff Luckey)
    15. 02:54 PM - Re: Start Solenoid Orientation (Jeff Luckey)
    16. 05:10 PM - Re: Re: Pitot tube slightly plugged... (Dj Merrill)
    17. 05:41 PM - Re: Re: Pitot tube slightly plugged... (RGent1224@aol.com)
 
 
 


Message 1


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    Time: 01:34:30 AM PST US
    From: "B Tomm" <fvalarm@rapidnet.net>
    Subject: ACF-50 Anti-corrosion between block and alternator
    mount... Michael, Since nobody has responded yet...I will offer my .02 It is my understanding that products like ACF-50 are used to prevent oxidation/corrosion from developing. If the part is already corroded, I would suggest removing the corrosion and then use the ACF-50 to prevent it from returning anytime soon. You may also look for a electrically conductive paste that will seal out the oxygen. There should be plenty of electrical pathway capacity through the mounting bolts regardless. Bevan -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Michael Burbidge Sent: Saturday, September 22, 2012 1:03 PM Subject: AeroElectric-List: ACF-50 Anti-corrosion between block and alternator mount... --> <mburbidg@gmail.com> When I took the old alternator mount off the engine, I noticed there was some corrosion on the engine block under the alternator mount. My new alternator (B&C) gets its ground through the mount. Can I use and anti-corrosion film such as ACF-50 on the block before bolting the mount to the engine? Or will that place resistance in the ground path for the alternator? Thanks, Michael-


    Message 2


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    Time: 06:41:59 AM PST US
    From: Bill Watson <Mauledriver@nc.rr.com>
    Subject: Re: Why did this AMP crimp on connection get singed
    and fail? Rayj, thanks for that. I found it and it helps. In the end, I think I'm getting reasonably good crimps given the equipment and parts I'm using. It's going to be a matter of inspecting each connection regularly for 'smoking' and to take even more care with each crimp. Bill do not archive On 9/22/2012 5:08 PM, rayj wrote: > > Bill, > > Search "switches with faston tabs" in the AeroElectric archives. They > discuss the discoloration of the faston insulation as the result of > switch failure. Time frame of sept 08. > > Raymond Julian > Kettle River, MN. > 9/22/12 > >


    Message 3


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    Time: 07:07:53 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Misprint in Z-16, v.12/ OV with Rotax generators?
    Not Ducati but I had a similar John Deere regulator for a 20 amp permanent magnet alternator fail full on. My fault as I started the engine with a dead battery. The voltage went high as the dead battery was not immediately ready to accept current which is not unusual for a fully discharged AGM battery. The regulator failed and thereafter let unregulated full alternator output through. The regulator failed even though the overvoltage disconnect relay was between the alternator and the regulator so the voltage must have risen faster than the relay could open when the engine started. I credit Bob's crowbar ovm for keeping the buss voltage clamped though and preventing any further damage. I guess the main point is that sometimes solid state devices can indeed fail ON instead of OFF. Ken On 22/09/2012 5:52 PM, s wrote: > --> AeroElectric-List message posted by: s<uuccio@gmail.com> > > Hello listers, > > Seems like there is a small misprint in Z16 v.12: the wire between > the 5A breaker (or is it a fuse?) and the S1 switch should be 18AWG > not 22AWG since its the same size as the fuse link. > > I was chatting to my favorite automotive mechanic the other day and > telling him I was planning to include an alternator disconnect relay > (as per Z16 or maybe Z17) in my electrical system. He said that he's > never heard of a Ducati regulator going in over voltage, he says they > usually just stop working. Does anyone know of anyone who's > experienced an OV problem with the inbuilt Rotax generator? > > Another question: can anyone explain why the alternator disconnect > wiring is more complex in Z16 than in Z17? What is the advantage of > doing it the Z16 way? > > Sacha Rebuilding a Kitfox IV with Rotax 80hp, almost there Sicily, > Italy > >


    Message 4


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    Time: 09:44:42 AM PST US
    Subject: Re: ACF-50 Anti-corrosion between block and alternator
    mount...
    From: Michael Burbidge <mburbidg@gmail.com>
    That's what I did. I cleaned off the corrosion and then put ACF-50 in between before bolting the new mount to the block. Sounds like that should be ok. Mike Sent from my iPhone On Sep 23, 2012, at 1:32 AM, "B Tomm" <fvalarm@rapidnet.net> wrote: > > Michael, > > Since nobody has responded yet...I will offer my .02 > > It is my understanding that products like ACF-50 are used to prevent > oxidation/corrosion from developing. If the part is already corroded, I > would suggest removing the corrosion and then use the ACF-50 to prevent it > from returning anytime soon. You may also look for a electrically > conductive paste that will seal out the oxygen. There should be plenty of > electrical pathway capacity through the mounting bolts regardless. > > Bevan > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Michael > Burbidge > Sent: Saturday, September 22, 2012 1:03 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: ACF-50 Anti-corrosion between block and > alternator mount... > > --> <mburbidg@gmail.com> > > When I took the old alternator mount off the engine, I noticed there was > some corrosion on the engine block under the alternator mount. My new > alternator (B&C) gets its ground through the mount. Can I use and > anti-corrosion film such as ACF-50 on the block before bolting the mount to > the engine? Or will that place resistance in the ground path for the > alternator? > > Thanks, > > Michael- > > > > > > > >


    Message 5


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    Time: 10:03:58 AM PST US
    From: "Jeff Luckey" <JLuckey@pacbell.net>
    Subject: Start Solenoid Orientation
    Group, I'm preparing some electrical hardware for my RV7 & this question came up: How should I orient the start solenoid, terminals up or down? I'm curious how G loading will affect the plunger. I'm planning to use this solenoid http://www.autopartswarehouse.com/sku/Standard/Starter_Solenoid/SISS581.html (a generic automotive type) because it is inexpensive & should be easily found in the future. In the picture at the above link, the solenoid appears "terminals down". Is that how it should be mounted in the airframe? In that orientation, any positive G loading will try to keep the contacts apart or open which is what I want. (don't want starter to inadvertently engage at the bottom of a hard pull). I think that the return spring in this device is pretty strong therefore it would take more than 6 Gs to get it to move but I thought I would pose the question to the group. Also, this solenoid has an "I" terminal which gets B+ when the solenoid is energized. (I think it is used to bypass an ignition ballast resistor in older cars) Does anyone have a schematic of the wiring inside this device? I'm curious how this "I" terminal is wired internally. ( I googled for about 20 minutes but could not find any info on this, which I though was odd ) So, I'm looking specifically for feedback on the following 2 questions: 1. applicability of this device for cranking a Lycoming 2. mounting orientation 3. internal schematic TIA, Jeff Luckey


    Message 6


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    Time: 10:31:32 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: ACF-50 Anti-corrosion between block and alternator
    mount... At 03:03 PM 9/22/2012, you wrote: When I took the old alternator mount off the engine, I noticed there was some corrosion on the engine block under the alternator mount. My new alternator (B&C) gets its ground through the mount. Can I use and anti-corrosion film such as ACF-50 on the block before bolting the mount to the engine? Or will that place resistance in the ground path for the alternator? The only way to you add resistance to the joint with such treatments is when the higher resistance contaminant is as hard or harder than base materials (alternator bracket and engine crankcase). For example, we've discussed the manner in which anti-corrosion dopes work in crimped terminals on aluminum wire. A wire grip and wire strands might appear to be full of dope but after the crimp, the PRESSURES applied to deform metal parts with intent to create gas-tight junctures is so much higher the compression strength of the 'contaminant' that it's extruded out of spaces where the metal hits the road. As you transition out of those metal upset spaces, the remaining dopant is squished out and remains in the voids becomes a barrier to moisture laden air. Back in my two-way-radio-days we used to pack coax cable connectors on tower joints with Dow Corning DC-4, a silicone grease the consistency of wheel-bearing grease. The connectors were then wrapped with 3+ layers of plastic tape (which would only stick to itself due to slickness of the coax and connectors underneath!), Such joints opened years later might have the tape nearly falling off due to UV and weather effects but the joints inside were as-new pristine. Suitable dopant used on the brightly cleaned and ready to mate surfaces of your alternator bracket and engine is incapable of raising joint resistance where adequate metal-to-metal contact and pressures are achieved. Remnants of the dopant not extruded out of the joint remain in non-contact areas and provide the desired barrier for ingress of moisture. There's a host of suitable materials. Electronic grade RTV (no corrosive type) comes to mind as a material with high operating temperatures but soft enough not to 'glue' things together. Chemical conversion coatings will only protect a surface and have no ability to fill gaps and preclude moisture incursion. You use those chemical conversion before assembly then use gap-filing dopants on top of that for the golden joint. Bob . . .


    Message 7


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    Time: 10:41:46 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: What crimper to use for B&C alternator field
    terminals... At 03:06 PM 9/22/2012, you wrote: > >Does anyone know what kind of crimper I use for the terminals used >on the field wire for the B&C alternators? Does one of the crimpers >from B&C work? Which one? > >Thanks, >Michael- Those are b-crimp terminals http://tinyurl.com/8j73sbp http://tinyurl.com/8hf6mo9 applied with a tool like the one shown from B&C I discovered this tool on eBay which appears to be the right one but there's not enough details in the ad to be sure. http://tinyurl.com/8hn8vxe I've ordered one for evaluation and will report my findings here on the List. Bob . . .


    Message 8


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    Time: 11:00:25 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Why did this AMP crimp on connection get singed
    and fail? At 04:08 PM 9/22/2012, you wrote: > >Bill, > >Search "switches with faston tabs" in the AeroElectric archives. >They discuss the discoloration of the faston insulation as the >result of switch failure. Time frame of sept 08. Yes . . . there was a 'rash' of failures manifesting in 'smoked joints' that started with loose rivets on the Carling switches. This prompted a lot of discussion and failure-analysis/tear-downs back about that time. Something to keep in mind as folks are unhappily blessed with such events. Look for a the loci of failure . . . sorta like a arson investigation. See which parts got hottest. These usually point to the area off poor connection where the degradation of the joints began. Several examples of over-heating in poor conduction areas are explored here: http://tinyurl.com/8d63v8x http://tinyurl.com/8zzkfbb http://tinyurl.com/8zzkfbb Whether bolting alternator brackets to crank-cases or keeping all the connections tight through a switch, the path to failure is the same. Increase in resistance increases heating and VOLTAGE DROP across a joint These two antagonists team up regeneratively to damage and perhaps fail the joint. Bob . . .


    Message 9


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    Time: 11:09:52 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: pitot tube
    At 06:58 PM 9/22/2012, you wrote: > >Bob, > > I'm interested, but I'm unwilling to take on any more projects > at this time. Maybe a couple of years down the road. When I > decide to take on another project I'll drop you a note. > >Just a couple of quick questions How many amps at what voltage would >be available and what would you imagine the overall dimensions to be? > >I'll keep my eyes out for stainless steel electrical properties and >drop you a note if I see anything that might be useful. Good. I've got about 100 back-burner projects, some of which get tid-bits of useful information added from time to time. It's that expansion of situational awareness that contributes to understanding of the whole . . . holler if you get either inspired or motivated . . . and thanks for the offer. Bob . . .


    Message 10


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    Time: 11:10:36 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Pitot tube slightly plugged...
    > >Stick the "V" end up in the hole in the fuel drain, gascolator, fuel >vent, etc, with the legs sticking out to the side. > >Remove before flight, but in theory air would be able to pass if you >accidentally left them in the fuel vent. > >Been doing this for a few years now and no more bug problem in the >fuel drains. An elegant solution Dj . . . how about some photos of these critters in place. Let's do a little one-pager for the AEC website archives. Bob . . .


    Message 11


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    Time: 11:13:59 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: ACF-50 Anti-corrosion between block and alternator
    mount... At 03:32 AM 9/23/2012, you wrote: > >Michael, > >Since nobody has responded yet...I will offer my .02 > >It is my understanding that products like ACF-50 are used to prevent >oxidation/corrosion from developing. If the part is already corroded, I >would suggest removing the corrosion and then use the ACF-50 to prevent it >from returning anytime soon. You may also look for a electrically >conductive paste that will seal out the oxygen. There should be plenty of >electrical pathway capacity through the mounting bolts regardless. > >Bevan Bingo! You get the gold star for this topic my friend. The paste or "dopant" need not be conductive for reasons I cited in the other posting. But their function is necessary to joint longevity and goes beyond repairs and protection of surfaces. Chemical treatment thicknesses are measured in diameters of molecules. Gap fillers have a much larger and equally important role to play . . . Bob . . .


    Message 12


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    Time: 01:31:06 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Start Solenoid Orientation
    At 12:02 PM 9/23/2012, you wrote: Group, I'm preparing some electrical hardware for my RV7 & this question came up: How should I orient the start solenoid, terminals up or down? I'm curious how G loading will affect the plunger. I'm planning to use this solenoid http://www.autopartswarehouse.com/sku/Standard/Starter_Solenoid/SISS581.html (a generic automotive type) because it is inexpensive & should be easily found in the future. In the picture at the above link, the solenoid appears "terminals down". Is that how it should be mounted in the airframe? In that orientation, any positive G loading will try to keep the contacts apart or open which is what I want. (don't want starter to inadvertently engage at the bottom of a hard pull). I think that the return spring in this device is pretty strong therefore it would take more than 6 Gs to get it to move but I thought I would pose the question to the group. Exactly. The g-load closing of starter contactors is one of those hanagar myths that has been around for a very long time . . . and repeated often enough it morphs into fact. That contactor mounted on the firewall orients the the terminals forward. A study of these pieces and parts http://tinyurl.com/96wy5mq shows that the contact bar is pushed against the insulated lid which retains the terminals. G-forces tending to close the contacts in this orientation would be achieved only if you flew into a mountainside. When oriented on a horizontal surface, you'd have to be in a wing-stripping push-over to close the contacts. I was working the B&C booth at OSH when one of the air-show famous showed up to buy a new starter and a starter contactor. After completing a performance it was discovered that his starter ring gear was trashed and the pinion on the starter damaged. The starter contactor was "stuck shut" which common wisdom of excited moment suggest was victim of daring-do g-loads. I didn't get to see the as-installed carcasses nor were we asked to do autopsies on the damaged parts. After some reflection in following months I concluded that he most likely suffered a stuck contactor at engine start up. But given the cockpit noise of these hi-performance machines and attention to upcoming demands on pilotage, the event went unnoticed. He probably flew his routine with a starter engaged and running. Also, this solenoid has an "I" terminal which gets B+ when the solenoid is energized. (I think it is used to bypass an ignition ballast resistor in older cars) Does anyone have a schematic of the wiring inside this device? I'm curious how this "I" terminal is wired internally. ( I googled for about 20 minutes but could not find any info on this, which I though was odd ) You're correct. This feature isn't used in cars with electronic ignition but would still be useful on a '57 Chevy. Few cognizant enthusiasts today are even aware of this feature or its significance. There are two popular form factors for this contactor. http://tinyurl.com/8my46tv There's a number of I-terminal references in this document http://tinyurl.com/9looejm So, I'm looking specifically for feedback on the following 2 questions: applicability of this device for cranking a Lycoming Works good, lasts a long time mounting orientation Doesn't really matter much but you'd have to go out of your way to mount it such that flight g-loads tended to close contacts. This is unlike popular starter contactors of yesteryear http://tinyurl.com/8fwygp4 which featured large area, low pressure contacts and massive solenoid armatures. Even in the "continuous duty" versions were not well suited to high-inrush duty of spinning up cranking motors. That's the best we had in 1960 but have not been seen in that service for many decades. But even these parts are exceedingly unlike to get closed under g-loads of flight. Now, there WAS a good reason for mounting them upside down on the firewall but that was for moisture reasons . . . that's another story of a CFD and hat-dance carried out at the Cessna Single Engine facility about 1980. internal schematic See figure 11-21 in the 'Connection. Functionally accurate. The "I" terminal in modern incarnations of a starter contactor is bridged in one stroke with the main terminals of the device. In this picture http://tinyurl.com/96wy5mq the "thin and light moving contacts" are propped up on a spring strut at right angles to the main current pathway. The end of this strut contacts the "I" terminal simultaneously with closure of the main terminals. Bob . . .


    Message 13


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    Time: 01:38:15 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Misprint in Z-16, v.12/ OV with Rotax generators?
    At 11:18 PM 9/22/2012, you wrote: Thanks Bob, I almost didn't mention it as I thought it was "obviously wrongh but now I'm glad I did as I learnt something! (Is there a detailed discussion of how each Z figure works somewhere that beginners can read?). Still wondering about the diff between the Z16 and Z17 alternator disconnect wiring. Just variations on a theme. Primary design goal is to achieve absolute control over energy from the alternator as seen by the rest of the airplane. Opening the DC pathway out of the rectifier-regulator does that. Opening the AC power into the regulator does too. AC is generally easier to control than DC for considerations of contact arcing. But given the low duty cycle of stressful events in these systems, either will do fine and last a long time. As Ken noted, the RR can be placed at risk for high rpm ops without having the battery connected. So while the control schemes presented in Z-16/17 are golden for the rest of the airplane, Z-17 carries the protection further back toward the alternator and would perhaps have saved Ken's RR from untimely demise due to the unloaded condition. I've not taken the time to really thrash through the physics of a PM regulator. Seems it SHOULD be designed to handle worst case failures including unloaded operations. It can probably be done but Z-17 is a work-around until the golden PM rectifier regulator comes along. Bob . . .


    Message 14


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    Time: 02:47:50 PM PST US
    From: "Jeff Luckey" <JLuckey@pacbell.net>
    Subject: Yesterday's Project - Show & Tell
    How about a little show-and-tell. I'm not sure that the embedded picture will come thru, (if it does not, I will re-post) Picture of a panel of containing a master solenoid, start solenoid, shunt, shunt fuses & ANL current limiter for the engine battery in my RV-7. Design Goals: 1. as compact as practical ( the mounting plate dimensions are 6" wide x 5.5" tall) 2. easy to install - (mounts to airframe w/ 4 screws) 3. easy to work on (all of the interconnections were made while sitting at my workbench as opposed to working in-position on the airframe) 4. easy to maintain (all fastenings are tapped into the base-plate thus not requiring access to the back of the panel after installation for maintenance) Mounting: To be mounted <~12" from the battery on the firewall Exercise for the reader: See if you can identify input & all outputs Any & all questions, comments, & constructive criticisms welcome. Jeff Luckey


    Message 15


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    Time: 02:54:01 PM PST US
    From: "Jeff Luckey" <JLuckey@pacbell.net>
    Subject: Start Solenoid Orientation
    Thanks Bob for your usual thorough mini-dissertation (I don't know how you find the time to deliver such thoughtful answers to the group but it is much appreciated! - If you are ever in Southern California, the cervezas are on me) -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Sunday, September 23, 2012 13:28 Subject: Re: AeroElectric-List: Start Solenoid Orientation <nuckolls.bob@aeroelectric.com> At 12:02 PM 9/23/2012, you wrote: Group, I'm preparing some electrical hardware for my RV7 & this question came up: How should I orient the start solenoid, terminals up or down? I'm curious how G loading will affect the plunger. I'm planning to use this solenoid http://www.autopartswarehouse.com/sku/Standard/Starter_Solenoid/SISS581.html (a generic automotive type) because it is inexpensive & should be easily found in the future. In the picture at the above link, the solenoid appears "terminals down". Is that how it should be mounted in the airframe? In that orientation, any positive G loading will try to keep the contacts apart or open which is what I want. (don't want starter to inadvertently engage at the bottom of a hard pull). I think that the return spring in this device is pretty strong therefore it would take more than 6 Gs to get it to move but I thought I would pose the question to the group. Exactly. The g-load closing of starter contactors is one of those hanagar myths that has been around for a very long time . . . and repeated often enough it morphs into fact. That contactor mounted on the firewall orients the the terminals forward. A study of these pieces and parts http://tinyurl.com/96wy5mq shows that the contact bar is pushed against the insulated lid which retains the terminals. G-forces tending to close the contacts in this orientation would be achieved only if you flew into a mountainside. When oriented on a horizontal surface, you'd have to be in a wing-stripping push-over to close the contacts. I was working the B&C booth at OSH when one of the air-show famous showed up to buy a new starter and a starter contactor. After completing a performance it was discovered that his starter ring gear was trashed and the pinion on the starter damaged. The starter contactor was "stuck shut" which common wisdom of excited moment suggest was victim of daring-do g-loads. I didn't get to see the as-installed carcasses nor were we asked to do autopsies on the damaged parts. After some reflection in following months I concluded that he most likely suffered a stuck contactor at engine start up. But given the cockpit noise of these hi-performance machines and attention to upcoming demands on pilotage, the event went unnoticed. He probably flew his routine with a starter engaged and running. Also, this solenoid has an "I" terminal which gets B+ when the solenoid is energized. (I think it is used to bypass an ignition ballast resistor in older cars) Does anyone have a schematic of the wiring inside this device? I'm curious how this "I" terminal is wired internally. ( I googled for about 20 minutes but could not find any info on this, which I though was odd ) You're correct. This feature isn't used in cars with electronic ignition but would still be useful on a '57 Chevy. Few cognizant enthusiasts today are even aware of this feature or its significance. There are two popular form factors for this contactor. http://tinyurl.com/8my46tv There's a number of I-terminal references in this document http://tinyurl.com/9looejm So, I'm looking specifically for feedback on the following 2 questions: applicability of this device for cranking a Lycoming Works good, lasts a long time mounting orientation Doesn't really matter much but you'd have to go out of your way to mount it such that flight g-loads tended to close contacts. This is unlike popular starter contactors of yesteryear http://tinyurl.com/8fwygp4 which featured large area, low pressure contacts and massive solenoid armatures. Even in the "continuous duty" versions were not well suited to high-inrush duty of spinning up cranking motors. That's the best we had in 1960 but have not been seen in that service for many decades. But even these parts are exceedingly unlike to get closed under g-loads of flight. Now, there WAS a good reason for mounting them upside down on the firewall but that was for moisture reasons . . . that's another story of a CFD and hat-dance carried out at the Cessna Single Engine facility about 1980. internal schematic See figure 11-21 in the 'Connection. Functionally accurate. The "I" terminal in modern incarnations of a starter contactor is bridged in one stroke with the main terminals of the device. In this picture http://tinyurl.com/96wy5mq the "thin and light moving contacts" are propped up on a spring strut at right angles to the main current pathway. The end of this strut contacts the "I" terminal simultaneously with closure of the main terminals. Bob . . . ----- No virus found in this message. Checked by AVG - www.avg.com


    Message 16


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    Time: 05:10:07 PM PST US
    Subject: Re: Pitot tube slightly plugged...
    From: Dj Merrill <deej@deej.net>
    On 9/23/2012 2:07 PM, Robert L. Nuckolls, III wrote: > > An elegant solution Dj . . . how about some photos > of these critters in place. Let's do a little one-pager > for the AEC website archives. > Hi Bob, I did a quick little write-up on my website at: http://deej.net/aviation/bug-plug/ Feel free to use the pictures and info on that page if you want to put something up on the AEC site. -Dj -- Dj Merrill - N1JOV Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/ Glastar Flyer N866RH - http://deej.net/glastar/


    Message 17


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    Time: 05:41:34 PM PST US
    From: RGent1224@aol.com
    Subject: Re: Pitot tube slightly plugged...
    Can you convert the document to PDF format so it can be easily saved Thanks, Dick In a message dated 9/23/2012 7:11:01 P.M. Central Daylight Time, deej@deej.net writes: --> AeroElectric-List message posted by: Dj Merrill <deej@deej.net> On 9/23/2012 2:07 PM, Robert L. Nuckolls, III wrote: > > An elegant solution Dj . . . how about some photos > of these critters in place. Let's do a little one-pager > for the AEC website archives. > Hi Bob, I did a quick little write-up on my website at: http://deej.net/aviation/bug-plug/ Feel free to use the pictures and info on that page if you want to put something up on the AEC site. -Dj -- Dj Merrill - N1JOV Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/ Glastar Flyer N866RH - http://deej.net/glastar/




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