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> Runs great cold then ...
pbob42
post Jun 21 2012, 04:06 PM
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Bringing back a '73 from a barn. Got her going. She starts great cold, first thing in the morning, cranks right up. She will only run for about 5 minutes and then peters out and won't start until the next morning.

Any thoughts?
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JawjaPorsche
post Jun 21 2012, 04:23 PM
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You failed to mention if you had FI or carbs. Have you clean the fuel tank and replaced the fuel filter?
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jsayre914
post Jun 21 2012, 04:40 PM
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so, after i searched your earlier threads...

you changed the fuel pump. did you change the fuel filtre? You also replaced all the fuel injection hoses. did you mix them up at the pump? you also said that huge clouds of smoke were comming out the tailpipe. is this the case for the five min run?



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pbob42
post Jun 21 2012, 06:35 PM
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QUOTE(jsayre914 @ Jun 21 2012, 03:40 PM) *

so, after i searched your earlier threads...

you changed the fuel pump. did you change the fuel filtre? You also replaced all the fuel injection hoses. did you mix them up at the pump? you also said that huge clouds of smoke were comming out the tailpipe. is this the case for the five min run?



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put in a new filter with the pump. I am thinking I might have some blockage - that filter is clear and only about 15% full. I am thinking that gas should about be filling it up.

Don't think I mixed the hoses. Can't imagine, it would run at all.

Pulled off the muffler - smoke went away so I can burn that out.
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ThePaintedMan
post Jun 21 2012, 06:39 PM
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So you do have carbs then (imagine so with a clear filter - those are only low pressure). That being said, my clear filter never fills either when running. Might have some blocked jets that get worse as the car runs, progressively getting more blocked as the sediment in the bowls gets thrown up and into them. Well, thats my guess and one of the first things I'd check.
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seanery
post Jun 21 2012, 06:39 PM
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Wasn't there a thread a couple weeks ago where the guy had a similar situation? New pump, fuel lines and filter, car would start then run a short bit bit, then done. I can't remember the resolution, but I think it might have been mixed lines or a kink/crease in the supply line. Maybe work backwards looking for a kink or blockage?

Good luck!
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pbob42
post Jun 21 2012, 07:00 PM
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QUOTE(seanery @ Jun 21 2012, 05:39 PM) *

Wasn't there a thread a couple weeks ago where the guy had a similar situation? New pump, fuel lines and filter, car would start then run a short bit bit, then done. I can't remember the resolution, but I think it might have been mixed lines or a kink/crease in the supply line. Maybe work backwards looking for a kink or blockage?

Good luck!


No - mine is FI, so that filter is probably my problem.
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ThePaintedMan
post Jun 21 2012, 07:08 PM
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Well don't take my word for it. But I was always under the impression that the clear filters were for low pressure systems. A higher pressure FI system (well above 4-5 PSI) might not work well with it, and in a worst case scenario, break the glass/plastic and spew gas. As far as the rest of the FI is concerned, I'm not the guy to ask. Dave Darling will be along soon with some good suggestions though.

One more thought though - with the pressure of a FI system, I would definitely think that clear filter would be full. Perhaps a blockage prior to the filter, or like these gentlemen said, lines crossed. Aren't the stock fuel pumps three outlets? Seems like it would be easy enough to mix up.
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pbob42
post Jun 21 2012, 07:15 PM
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QUOTE(ThePaintedMan @ Jun 21 2012, 06:08 PM) *

Well don't take my word for it. But I was always under the impression that the clear filters were for low pressure systems. A higher pressure FI system (well above 4-5 PSI) might not work well with it, and in a worst case scenario, break the glass/plastic and spew gas. As far as the rest of the FI is concerned, I'm not the guy to ask. Dave Darling will be along soon with some good suggestions though.

One more thought though - with the pressure of a FI system, I would definitely think that clear filter would be full. Perhaps a blockage prior to the filter, or like these gentlemen said, lines crossed. Aren't the stock fuel pumps three outlets? Seems like it would be easy enough to mix up.


Well the third line is a primer line. An aftermarket pump was remommended where that third line is eliminated.

I can't see how the car would run at all if the pump was backward. It would be sucking the gas away from the injectors.
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76-914
post Jun 21 2012, 08:37 PM
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the filter should be on the gravity side, not the pressure side!
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pbob42
post Jun 21 2012, 10:15 PM
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QUOTE(76-914 @ Jun 21 2012, 07:37 PM) *

the filter should be on the gravity side, not the pressure side!

It is on the gravity side, but I figured the gravity would keep it full.

The more I read up I am thinking it is the pressure sensor. The plugs that came out of the car were fouled. Running rich and stalling out after a few minutes seem to point to pressure sensor.
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TheCabinetmaker
post Jun 22 2012, 05:28 AM
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I would suspect the head temp sensor. Do an ohms test when warm. It should be around 250 or less. Im assuming this is a djet.
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Java2570
post Jun 22 2012, 06:56 AM
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QUOTE(vsg914 @ Jun 22 2012, 07:28 AM) *

I would suspect the head temp sensor. Do an ohms test when warm. It should be around 250 or less. Im assuming this is a djet.



(IMG:style_emoticons/default/agree.gif) Sounds like it could be Cylinder Head Temp Sensor......

Follow the Anders page and make sure you have all the basics checked out first;
you'll save your self lots of time chasing tails.
You may very well have several problems going on at the same time....thats what I found with my car. It does sounds like you are getting too much fuel and flooding out which is indicative of the CHT being bad.
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pbob42
post Jun 22 2012, 07:55 AM
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QUOTE(Java2570 @ Jun 22 2012, 05:56 AM) *

QUOTE(vsg914 @ Jun 22 2012, 07:28 AM) *

I would suspect the head temp sensor. Do an ohms test when warm. It should be around 250 or less. Im assuming this is a djet.



(IMG:style_emoticons/default/agree.gif) Sounds like it could be Cylinder Head Temp Sensor......

Follow the Anders page and make sure you have all the basics checked out first;
you'll save your self lots of time chasing tails.
You may very well have several problems going on at the same time....thats what I found with my car. It does sounds like you are getting too much fuel and flooding out which is indicative of the CHT being bad.


I'll get the ohm meter out this morning. I'll check the temp sensor and the coils on the pressure sensor and let you guys know.
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rhodyguy
post Jun 22 2012, 09:39 AM
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fuel screen/sock in the tank? it gets plugged up with debris and collapses under pump vacuum. shut the engine down and over time as the vacuum equalizes the screen allows some fuel to pass. then more crap in the tank gets drawn to the screen and the cycle repeats. start at the beginning of the fuel flow.

k
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jmill
post Jun 22 2012, 10:32 AM
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QUOTE(rhodyguy @ Jun 22 2012, 10:39 AM) *

fuel screen/sock in the tank? it gets plugged up with debris and collapses under pump vacuum. over time as the vacuum equalizes the screen allows some fuel to pass. then more crap in the tank gets drawn to the screen and the cycle repeats. start at the beginning of the fuel flow.

k



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That initial white smoke was most likely water in the fuel. That sock might be clogged up with slime and/or crud.
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