AeroElectric-List Digest Archive

Thu 06/24/04


Total Messages Posted: 11



Today's Message Index:
----------------------
 
     1. 08:06 AM - LVWM (Fiveonepw@aol.com)
     2. 08:23 AM - Long-EZ earth  (Glenn Rainey)
     3. 09:43 AM - batteries//load dump testing etc (Paul Messinger)
     4. 09:49 AM - Re: Automotive Landing Lights? (Ken)
     5. 09:52 AM - Re: engine hot starting and more on batteries (Paul Messinger)
     6. 01:47 PM - Re: Noise problems with JPI EDM-900 and autopilot (Jeff Hildebrand)
     7. 03:49 PM - Re: Transponder connection (Robert L. Nuckolls, III)
     8. 05:19 PM - Re: Re: Cont VS Bendix injection systems (George Braly)
     9. 07:06 PM - Transponder connection (Mark Sherman)
    10. 08:01 PM - Re: Re: Cont VS Bendix injection systems (Paul Messinger)
    11. 08:59 PM - Re: Re: Cont VS Bendix injection systems (George Braly)
 
 
 


Message 1


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    Time: 08:06:33 AM PST US
    From: Fiveonepw@aol.com
    Subject: LVWM
    --> AeroElectric-List message posted by: Fiveonepw@aol.com I have recently noticed my LVWM lamp briefly and intermittently turning on immediately after liftoff. This continues until about 2000' AGL then goes away. The only time I normally see it is when it should be on, such as when engine is not running or under about 600 rpms. Loose belt? Only difference in operation is higher ambient temps lately. I would have checked voltage but was busy getting off the ground... Thanks in advance- Mark -6A, Z-11 with generic VR-66 regulator, batt & reg on firewall, B&C 40A alternator, E3D Lyc. do not archive


    Message 2


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    Time: 08:23:10 AM PST US
    From: Glenn Rainey <nimbusaviation@yahoo.com>
    Subject: Long-EZ earth
    --> AeroElectric-List message posted by: Glenn Rainey <nimbusaviation@yahoo.com> My Long-EZ was built with a copper tube earth from firewall to nose, curiously with a joint to a smaller pipe diam at the station of the panel bulkhead. Disliking that joint, I pulled the foward section, but the main length of the pipe will have to stay, and carry current. So.. will 4AWG suffice for the 3 ft or so forward to the battery (with Hall sensor!), and similarly 4AWG back from the firewall to the starter (maybe 3 - 4 ft)? I will be turning an O-235-L2C with one of those, umm.. 'light weight' starters. Maybe some wt saving, and easier to work with 4AWG. regards from Scotland, Glenn Rainey LEZ project (builder #2) __________________________________ http://promotions.yahoo.com/new_mail


    Message 3


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    Time: 09:43:06 AM PST US
    From: "Paul Messinger" <paulm@olypen.com>
    Subject: batteries//load dump testing etc
    --> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com> ----- Original Message ----- From: "Robert L. Nuckolls, III batteries" <bob.nuckolls@cox.net> > > > > need for a float charger to keep it topped off like the Panasonic does. > > I don't know of anyone who has found it necessary to keep > a float charger on a Panasonic battery to achieve satisfactory > service . . . and there are many hundreds of Panasonic batteries > flying in airplanes. > >> Bob; Perhaps you missed the background on my comment and the basis for the "need for float charger" I was responding to a statement that "ALL" batteries self discharge more or less at the same rate. I have data that shows that some have a TEN times lower self discharge rate that others of the same general type. (AGM). Panasonic will loose as much as 36% of its charge in 12 months while others may loose only 5%. Thus IF you store your aircraft for the 6 months you may need a float charger with the Panasonic type battery. Other (expensive) brands can store for 12 months with no noticable loss of capacity. But how many ownersreally do (store for months on end) that anyway. That said, Panasonic and the similar other brands often recommended on this list are simply amazing in performance based on my testing. They can start large auto engines and have Twice the CCA of the flooded cell certified aircraft batteries. A real sleeper (in real performance) that YOU have been recommending for years. Only down side I can find is the somewhat weak terminal lugs and that is not a problem in my opinion if the user also follows another of your great recommendations and use the very flexable welding cable for the short battery to aircraft leads. Paul


    Message 4


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    Time: 09:49:05 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Automotive Landing Lights?
    --> AeroElectric-List message posted by: Ken <klehman@albedo.net> FWIW the plastic automotive projector lamps that I am using had a metal strip inside the housing to cut off the top of the light beam. I removed them with needle nose pliars and I believe the broader vertical beam will be more suitable for aviation use. I used both driving and fog lamps so it may have been only one or the other that had these metal strips inside. Ken Rob Housman wrote: >--> AeroElectric-List message posted by: "Rob Housman" <RobH@hyperion-ef.com> > >The lens tells you almost nothing about the beam pattern. What you need is >a reflector that is an accurate parabolic shape in order to deliver a narrow >(i. e., focused) beam of light. The lens merely scatters (more or less, >depending on its design) the light bounced off the reflector surface. The >reflectors in such systems as the very bright lights (see: >http://www.spectrolab.com/DataSheets/SX16/ILS_SX-16.pdf) used on police >helicopters, for example, are relatively deep electroformed nickel parabolic >shapes with coatings to enhance the reflectivity, and these can deliver >(with a xenon short arc lamp) a beam spread of less than 5 degrees. >Automotive headlamps are never going to match that kind of performance, but >as Bob has said, 3 watts from a cheap lantern can do the job. > >


    Message 5


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    Time: 09:52:31 AM PST US
    From: "Paul Messinger" <paulm@olypen.com>
    Subject: Re: engine hot starting and more on batteries
    --> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com> I truly do not want any to reply to this as we have beat it to death. Until someone has a real concrete set of info/test data; I will continue to recommend that Bob's approach on batteries be followed. Its been proven to be reliable, low cost, and safe. What more can one ask in today's world? Brian; If you recall I never questioned that what you were quoting was not "better" I only (from day one was asking for some backup data) as to how much better and never seemed to get a reply. To me it is not argumentative to keep asking for backup data that would define what "better" is or how much "shorter" life was and under exactly what conditions that data applied to. You have finally said you had no real test data (and neither do I) to refer to that provided definitive info on exactly what was to be gained that an engineer (vs. chemist) could look at and evaluate to see if it was cost or safety effective in his/her aircraft. I have been unable to get any definitive data as to what if any real benefit a fancy expensive 3 charge charger will do for the average experimental owner builder. Until such time as data is made available I can see no reason to consider deviation from what Bob has suggested as it has been demonstrated to be a good way to do as states above. Paul ----- Original Message ----- From: "Brian Lloyd" <brianl@lloyd.com> > Clearly you are going to argue until the cows come home. Feel free. I have presented information I consider to be significant. Hopefully people will make up their own minds about this. >


    Message 6


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    Time: 01:47:35 PM PST US
    From: "Jeff Hildebrand" <jhildebrand@crownequip.com>
    Subject: Noise problems with JPI EDM-900 and autopilot
    --> AeroElectric-List message posted by: "Jeff Hildebrand" <jhildebrand@crownequip.com> After spending a few hours isolating our intercom and other components, we found that it wasn't radiated noise from the power bus. It turns out that it was radiated noise from the intercom wire that connects the autopilot chime to the intercom. It turns out that the volume was set too high on the STEC 55x autopilot. When it was set correctly the noise disappeared. For anyone out there with an STEC 55x autopilot, make sure that the volume pot is set correctly. Jeff Hildebrand C-GSPH www.lancaires.com -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Trampas Subject: RE: AeroElectric-List: Noise problems with JPI EDM-900 and autopilot --> AeroElectric-List message posted by: "Trampas" <tstern@nc.rr.com> Well the noise is either coming from power bus or from some sort of radiated noise. To see if radiated power intercom from separate power supply, like an automotive "jump box". If noise is still there it is a radiated noise from RF or magnetic fields. This is most likely not the problem. The more likely problem is that the units are generating noise on power bus. To check this take one of the units and power it from the "jump box" while keeping the unit grounds connected. If noise goes away, you most likely have a unit which generates noise on power bus. Sometimes electronic devices have power supplies which produce noise spikes on power bus. If the device is doing this often placing a diode inline with the device will remove the noise. Other times the device draws large amounts of power for brief periods which generates noise on power bus. In these cases placing an inductor/capacitor filter as Bob has outlined fixes the problem. Either way I would personally recommend an inductor/cap filter on the intercom power as that power supply noise is really common. Regards, Trampas -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jeff Hildebrand Subject: AeroElectric-List: Noise problems with JPI EDM-900 and autopilot --> AeroElectric-List message posted by: "Jeff Hildebrand" <jhildebrand@crownequip.com> We are having noise problems with our Lancair ES. When we have the JPI EDM-900 engine analyzer and the STEC 55x autopilot on at the same time, we get a static noise in our headsets. When I turn off either one, the noise will go away. It seems to be coming from the EDM-900, because when I have the autopilot on already and I start the EDM it gives a little bit of static on the startup sequence, then it is consistent after this. When I have the EDM on already, and I turn on the autopilot, the static is there immediately. This noise is there when the engine is on or off. Where do I go from here? How do I diagnose the problem and fix it? Thanks, Jeff Hildebrand Lancair ES C-GSPH www.lancaires.com <http://www.lancaires.com/> == == == ==


    Message 7


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    Time: 03:49:45 PM PST US
    From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
    Subject: Re: Transponder connection
    --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net> At 11:59 AM 6/23/2004 -0700, you wrote: >--> AeroElectric-List message posted by: Mark Sherman ><msherman95632@yahoo.com> > >About the transponder connection question I ask >earlier, It was miswritten, the terminals are crimped >not soldered. But the question remains. > >Mark S. Mark, for some reason I didn't see the original post come through. Repeat your question please? Bob . . . ----------------------------------------- ( Experience and common sense cannot be ) ( replaced with policy and procedures. ) ( R. L. Nuckolls III ) -----------------------------------------


    Message 8


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    Time: 05:19:19 PM PST US
    Subject: Re: Cont VS Bendix injection systems
    From: "George Braly" <gwbraly@gami.com>
    --> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com> Paul, The TCM starting issue has virtually nothing to do with "flushing hot fuel from the system." Rather, it has everything to do with the temperature of the internal components of the mechanical fuel pump that come into contact with new fuel from the tank. If those components are hot enough to flash to vapor a significant portion of the hydrocarbon components of the new incoming fuel stream - - then there will be a "bloom" of vapor as the new fuel hits the inlet portion of the mechanical fuel pump - - which will then nicely suffer a classic vapor lock as the pump inlet "suction" is relieved by the bloom of fuel vapor and the pump is no longer able to pull (suck) fuel uphill to the inlet of the mechanical pump. It is not helpful to an understanding of the problem to try to deal with anything that happens downstream of that point - - as frankly, "HOT" downstream of the mechanical pump is usually helpful to the final result, not harmful. If, during cranking or subsequent operation, a gram of fuel vaporizes in one of the small stainless fuel lines, it is still a gram of fuel that ends up going into the cylinder induction plumbing and eventually into the cylinder and burning just like it would if it were liquid when it entered or exited the fuel injector. Regards, George -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Paul Messinger Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems --> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com> I will not get into a long reply other than to say that the specific Cont system I remarked about has a Single speed pump. Its a different cont or what ever system that have a dual speed pump. There is NO difference in fuel flow to the engine with or without the aux pump running (vs the engine driven pump when the engine is running). Bottom line is the cont system I am talking about had far less hot fuel to dump out of the engine lines before the starting can occur. Its not just the hot fuel in the lines to the cyl that boil but even the fuel in the pumps boil when it gets to the final very low pressure poing near the cyl injection points You are talking about different variations with dual speed pumps etc. In any event the Cont system I had was simple to hot start and the bendix system I had was very hard to hot start due to the inabilty to flush hot fuel from the engine. I will end this discussion with this post as its really off the subject Paul ----- Original Message ----- From: "Gary Casey" <glcasey@adelphia.net> Subject: AeroElectric-List: Re: Cont VS Bendix injection systems > --> AeroElectric-List message posted by: "Gary Casey" <glcasey@adelphia.net> > > I feel the need to comment on some of Paul's observations regarding the > Continental vs. "Bendix" fuel injection systems. There is no electrical > content here, so pardon us: > > <<The engine driven pump is a Positive displacement pump and is able to use > an > Aux pump with no change in performance. (no concern about HI or LOW pump > setting or changes in mixture with aux on or off) > > The pump output pressure is independent of altitude or ambient air > conditions.>> > > I believe the opposite is true - the fuel flow in the Bendix system is > independent of inlet pressure until it is insufficient for full flow (about > 15 psi), while the flow in the Continental system is sensitive to inlet > pressure and there have been accidents caused by the pilot incorrectly > choosing between high and low boost pump settings. In fact, if the mixture > is observed to change when the boost pump is turned on it should be > considered a defect. One important difference - the fuel flow rate in the > Continental system is also independent of another thing - the air flow into > the engine. The fuel flow in the Bendix system is inherently proportional > to air flow and independent of engine speed and inlet pressure. The > Continental system (unless the altitude-compensated version is used) does > not compensate for air density, while the fuel flow in the Bendix system is > proportional to the square root of inlet air density, essentially half > correcting for altitude and inlet air temperature. And the idle fuel flow > control is essentially the same in both systems, being a function of > throttle position, not air flow. > > <<The pump has a built in bypass as well as a built-in Vapor separator and > fuel > return to the tank requirement. The aux pump can flush and replace hot fuel > with cool fuel. > > Bendix system cannot flush the fuel past the firewall as there is no fuel > return setup. In a hot start condition a significant amount of fuel must be > purged from the system and out the exhaust before the engine can run. > > In the Cont system the aux pump can purge all the fuel except the small > amount in the line to and the lines from the flow divider. This is estimated > to be 80% or more of the total fuel in the engine compartment (there is > really only a very small amount of fuel in the non purgable part of the > system). Thus the Cont design greatly reduces the amount of hot fuel that > must be disposed of in a hot start.>> > > True, except that the Continental system doesn't purge fuel all the way to > the spider, but to the fuel control valve. The Bendix system relies on > pressure being maintained between the pump and within the fuel control servo > to prevent boiling in that area. If the pressure bleeds off after shutdown > there is a problem in the fuel pump that should be corrected. And hot fuel > doesn't cause the problem - it is the fuel vapor that is the issue. In both > systems it can be assumed that all the fuel in the spider is boiled out, and > the residual fuel from the distributor back to the fuel control valve may or > may not be partially vapor. > > And I think Paul mistyped - all Continental engines have the Continental > system except for those where the customer insisted on the Bendix system (I > think the Beech Duke is one of those). I don't know of a single case where > a Lycoming buyer selected the Continental system even though the Bendix > system, now manufactured by Precision Airmotive, has no corporate ties to > Lycoming. Yes, the venturi in the Bendix system does cause a manifold > pressure drop, but I don't know of any data that shows the system is more > prone to icing because of it. > > <<I have extensive experience in the two systems and I would never, by > choice > fly with an engine, using the Bendix system or at least as described above. > "Paul Messinger">> > > While the hot starting issue may be an area where the Continental has an > advantage, I don't think there have been any fatalities caused by hot start > problems. There have been fatalities caused by improper boost pump > operation in aircraft equipped with the Continental system. That, and the > fact that the Bendix system is at least partially compensated for air > density, are the reasons I prefer the Bendix system. > > Gary Casey > > == == == ==


    Message 9


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    Time: 07:06:12 PM PST US
    From: Mark Sherman <msherman95632@yahoo.com>
    Subject: Transponder connection
    --> AeroElectric-List message posted by: Mark Sherman <msherman95632@yahoo.com> Good afternoon Bob. I am installing a Garmin GTX 320A transponder with a Ameriking AK 350 encoder in my Zenith 701. There was no installation manual with the unit so I downloaded one from there web site. The encoder came with a cable, with a plug on one end for the encoder and bare wires on the other end for the transponder. I want to ensure that I am reading the installation manual correctly. They show a drawing of a 25 pin d-sub and pin-out definitions. The widest part of the connector is at the top with pin one at top row left and pin 25 at bottom row right. What it doesn't say is if this is the back of the plug that I will be soldering to, or the front of the plug that plugs into the transponder. Which would reverse the pins. My best guess is, it is the back that I will be soldering to. Can anyone confirm this? It is very expensive to have the smoke put back into the box so I don't want to let any out. Thanks Mark S. __________________________________ http://promotions.yahoo.com/new_mail


    Message 10


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    Time: 08:01:39 PM PST US
    From: "Paul Messinger" <paulm@olypen.com>
    Subject: Re: Cont VS Bendix injection systems
    --> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com> I think you missed my point. I agree with much of your comment. However; My point is that the secret is cooling the mechanical pump with cold fuel from the cold electric pump. Something not possible with the Bendix system. Fuel from the electric pump is pressurized above vapor pressure and does not vaporize at the hot engine pump. Further the cool fuel is pushed past the pump into the mixture assy where it is also cooled and exchanged even with the mix control in idle cutoff. Even if there is some initial vapor produced it is purged back into the tank and is not a factor. I assume one runs the electric pump long enough to cool things down a little. Worked for me at 6,000ft in 110F heat soaked aircraft many times when other acft ran the batterys down trying to start. Once properly cooled enough and considering that need not be much, with the pressure supplied by the electric pump it eliminates vapor lock during the critical start. There is always electric pump pressure at the inlet and thruout the mech pump and mix assy from the electric pump during its operation and thus no possible suction to allow vapor lock at the inlet of the pump. I hope you review the Cont system (in the 1971 book) was referring to and not some later system. The key to my point is circulation of fuel works and it worked for me too many times to count and the Bendix system design did not permit this and was, in most pilots (I have talked to) experience hard to 'hot' start. If you have an alternative why there is such a dramatic difference in the Bendix system VS the Cont system as used in the S35 ( I am specifically talking about that system and not other versions) I would be interested. I found hot starts to be a non event! I have never been able to hot start the Bendix system with out lots of cranking as one often makes a hot start into a severely flooded engine start. I have never met a pilot that did not have problems with the Bendix system and most failed to accept that in the S35 it could be a non event. To me as an engineer and mechanic the key is the ability to replace most of the hot fuel and also cool most of the fuel system prior to any attempt to crank the engine. Paul ----- Original Message ----- From: "George Braly" <gwbraly@gami.com> Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems > --> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com> > > > Paul, > > The TCM starting issue has virtually nothing to do with "flushing hot > fuel from the system." > > Rather, it has everything to do with the temperature of the internal > components of the mechanical fuel pump that come into contact with new > fuel from the tank. > > If those components are hot enough to flash to vapor a significant > portion of the hydrocarbon components of the new incoming fuel stream - > - then there will be a "bloom" of vapor as the new fuel hits the inlet > portion of the mechanical fuel pump - - which will then nicely suffer a > classic vapor lock as the pump inlet "suction" is relieved by the bloom > of fuel vapor and the pump is no longer able to pull (suck) fuel uphill > to the inlet of the mechanical pump. > > It is not helpful to an understanding of the problem to try to deal with > anything that happens downstream of that point - - as frankly, "HOT" > downstream of the mechanical pump is usually helpful to the final > result, not harmful. > > If, during cranking or subsequent operation, a gram of fuel vaporizes > in one of the small stainless fuel lines, it is still a gram of fuel > that ends up going into the cylinder induction plumbing and eventually > into the cylinder and burning just like it would if it were liquid when > it entered or exited the fuel injector. > > Regards, George >


    Message 11


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    Time: 08:59:49 PM PST US
    Subject: Re: Cont VS Bendix injection systems
    From: "George Braly" <gwbraly@gami.com>
    --> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com> TCM has a basic system that requires an electric boost pump. Cessna , Beech and others, at different times have provided either single speed boost pumps or two speed boost pumps, depending pretty much on which side of the bed some engineer and the FAA got up on the day the decision was made. The two speed pumps are very nice to have and very useful. I have seen a vapor lock so bad on a normally aspirated IO-550 that took off from Bullhead City, Az - - with 100+F new fuel (above ground tanks) loaded into the airplane - - that it vapor locked about 120 seconds after takeoff. HARD vapor lock. LOW boost did not even touch the problem. It took FULL RICH and HIGH boost to get the engine running again before we hit the terrain. One then current space shuttle mission specialist on board (PIC), me, and two teenagers. It made for some interesting Crew Resource Management. Regards, George -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Paul Messinger Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems --> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com> I think you missed my point. I agree with much of your comment. However; My point is that the secret is cooling the mechanical pump with cold fuel from the cold electric pump. Something not possible with the Bendix system. Fuel from the electric pump is pressurized above vapor pressure and does not vaporize at the hot engine pump. Further the cool fuel is pushed past the pump into the mixture assy where it is also cooled and exchanged even with the mix control in idle cutoff. Even if there is some initial vapor produced it is purged back into the tank and is not a factor. I assume one runs the electric pump long enough to cool things down a little. Worked for me at 6,000ft in 110F heat soaked aircraft many times when other acft ran the batterys down trying to start. Once properly cooled enough and considering that need not be much, with the pressure supplied by the electric pump it eliminates vapor lock during the critical start. There is always electric pump pressure at the inlet and thruout the mech pump and mix assy from the electric pump during its operation and thus no possible suction to allow vapor lock at the inlet of the pump. I hope you review the Cont system (in the 1971 book) was referring to and not some later system. The key to my point is circulation of fuel works and it worked for me too many times to count and the Bendix system design did not permit this and was, in most pilots (I have talked to) experience hard to 'hot' start. If you have an alternative why there is such a dramatic difference in the Bendix system VS the Cont system as used in the S35 ( I am specifically talking about that system and not other versions) I would be interested. I found hot starts to be a non event! I have never been able to hot start the Bendix system with out lots of cranking as one often makes a hot start into a severely flooded engine start. I have never met a pilot that did not have problems with the Bendix system and most failed to accept that in the S35 it could be a non event. To me as an engineer and mechanic the key is the ability to replace most of the hot fuel and also cool most of the fuel system prior to any attempt to crank the engine. Paul ----- Original Message ----- From: "George Braly" <gwbraly@gami.com> Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems > --> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com> > > > Paul, > > The TCM starting issue has virtually nothing to do with "flushing hot > fuel from the system." > > Rather, it has everything to do with the temperature of the internal > components of the mechanical fuel pump that come into contact with new > fuel from the tank. > > If those components are hot enough to flash to vapor a significant > portion of the hydrocarbon components of the new incoming fuel stream - > - then there will be a "bloom" of vapor as the new fuel hits the inlet > portion of the mechanical fuel pump - - which will then nicely suffer a > classic vapor lock as the pump inlet "suction" is relieved by the bloom > of fuel vapor and the pump is no longer able to pull (suck) fuel uphill > to the inlet of the mechanical pump. > > It is not helpful to an understanding of the problem to try to deal with > anything that happens downstream of that point - - as frankly, "HOT" > downstream of the mechanical pump is usually helpful to the final > result, not harmful. > > If, during cranking or subsequent operation, a gram of fuel vaporizes > in one of the small stainless fuel lines, it is still a gram of fuel > that ends up going into the cylinder induction plumbing and eventually > into the cylinder and burning just like it would if it were liquid when > it entered or exited the fuel injector. > > Regards, George > == == == ==




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