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Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 08, 2022 10:17PM

Start car idles great, go for a drive the vair runs great no issues, idles well at lights, good acceleration etc.
You get home get out of the car let it idle for a bit. After 2 or 3 or 4 minutes it just decides to quit, whats up with that?!
Restart and it still has difficulty ilding, crazy.

Your experience?

Joel
Cave Creek, AZ
1965 Corsa 140 tele

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Re: Many of you have experienced this...
Posted by: playerpage ()
Date: September 09, 2022 04:13AM

Sounds like a fuel pump issue. Sometimes with nothing else wrong with it the electric pumps can get clogged from impurities in the fuel, in the tank, Etc. Makes them run in spurts.

You can try changing out that little filter that they have attached directly to them, but you may find that your only option is to completely replace them.

All things being equal, my car can do that sometimes too. I'm pretty sure that that's what's going on with me. But the thought of getting under there and doing it again, even though it's a straightforward job, just makes me tired. I'm going to live with it for the rest of this season and then do all the little jobs at once over the winter, including that and replacing the fuel tank.

You may also want to consider checking your spark plugs and see how dirty they are...

Eric C. Player
Fargo, North Dakota
MEMBER: CORSA National, Central Coast CORSA, South Coast CORSA, Vintage CORSA, Sfba CORSA, and Great Plains Corvair Club.
THEN: 1965 Monza 110, Canary Yellow - 1965 Corsa 180 Turbo, Red - 1966 Monza 110, Purple - 1967 Monza 140, Red - 1966 500 110, Black; nicknamed "Shadow" - 1965 Monza 110, Camaro Yellow; nicknamed "Silver"
NOW: 1966 Corsa 180 Turbo, Blue; nicknamed "Bluvair"
---------------------------------------
"He cautioned me not to take notes. It would not have helped if I had, as he would start a paragraph with, 'It is therefore obvious. . .'
and go on from there to matters which may have been obvious to him and God but to no one else."
-- Robert A. Heinlein, character of Daniel B. Davis, 'The Door Into Summer.'



Edited 2 time(s). Last edit at 09/09/2022 04:15AM by playerpage.

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Re: Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 09, 2022 06:51AM

Sometimes I feel like im the last person still running mechanical fuel pump.
I replaced pump 1 year ago just before I tore up the diff and had it rebuilt.
Fuel pump has like 5 miles on it. Doesnt mean thats not the culprit.
Plugs are all good.

Joel
Cave Creek, AZ
1965 Corsa 140 tele

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Re: Many of you have experienced this...
Posted by: playerpage ()
Date: September 09, 2022 07:01AM

I kept my last Corvair mechanical, I get it.

If it's a new mechanical pump, maybe it's just simply vapor lock? I know there are a few solutions to that, but isn't it just kind of otherwise par for the course?

It also is possible that the gasket in the pump is bad or dissolved while sitting and is occasionally blocking up the pump. The consensus here on the boards that I've been reading is that the newly manufactured mechanical fuel pumps are pretty much garbage.



Edited 3 time(s). Last edit at 09/09/2022 07:05AM by playerpage.

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Re: Many of you have experienced this...
Posted by: Brizo ()
Date: September 09, 2022 10:08AM

It sounds like the fuel pump is weak and its not pumping much at idle speeds. It was ok and getting by when you were driving faster.
Disconnect a line from a carb, and see how much volumn its pumping at cranking and at idle rpm. Many of the newer pumps made from a heavy zink alloy are warping at the base causing internal leakage.

Dan Brizendine, Circle City Corvairs
'64 8 door Greenbrier, +.060, stroked 1/4", 186 ci.140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

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Re: Many of you have experienced this...
Posted by: jamesolefjensen ()
Date: September 09, 2022 10:50AM

Maybe the distributor vacuum advance canister went south (assuming that it is connected to full vacuum).

James
65 Corsa
SF Bay Area

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Re: Many of you have experienced this...
Posted by: irfgt ()
Date: September 09, 2022 01:03PM

The vacuum advance should not be connected to a full vacuum port unless it is a turbo.

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Re: Many of you have experienced this...
Posted by: irfgt ()
Date: September 09, 2022 01:04PM

More than likely a carb problem and not fuel pump unless it is producing too much pressure.

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Re: Many of you have experienced this...
Posted by: link9711 ()
Date: September 09, 2022 06:41PM

Hi all Sounds to me like a carb over heat problem and the gas is boiling and one point in the base of the carb.When driving theres air moving around inside the eng compartment but when you stop the heat from the heads may be coming up and heating the carb base and causing the gas to vaporize and starts vapor flooding would not take much at a idle to make the car die.I would take the temp of the carb when its idling ok and all covers closed.and when it starts dieing retake the temp at the carb bowl.Just a idea. Hope this helps.

link9711
63 monza spyder
san antonio,tx

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Re: Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 09, 2022 07:35PM

thanks for the diagnosis, ill report back.
for the record its a newly rebuilt 390 holley center mount

thank you

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Re: Many of you have experienced this...
Posted by: corventure Dave ()
Date: September 10, 2022 01:26AM

Also may want to check voltage to the coil. Plus the coil may be failing. I have seen new off shore coils that overheat and fail almost right away. If the coil was exposed to too much voltage at one time, it could be an issue.

Also be sure the fuel filter sock on the fuel sending unit in the tank is not encrusted and limiting fuel flow.

Just another thing to check.

Corventure Dave

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Re: Many of you have experienced this...
Posted by: Lane66m ()
Date: September 10, 2022 03:56AM

Does the engine have Pertronix Ignitor Unit? If it does, it may be failing.

Here the troubleshooting link for the Ignitor. Just in case.

[www.pertronix.com.au]

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Re: Many of you have experienced this...
Posted by: link9711 ()
Date: September 10, 2022 06:34AM

Hi again quick question what type of base gasket do you have on the carb the reason I ask is I have a friend that has a mustang and he has the same carb on it.He could not get it to run right I looked at it and tryed to adjust the idel fuel mix turned both screws and did not make any difference.What we found is he had a big gasket with a open hole and it took a gasket with 4 holes in it to block off the ports also with the big gasket he was getting vac to the dist all the time when we put the right gasket then could adjust both sides fuel mix and the vac to the dist was only when given throttle would advance it made all the difference in the world.easy check inplug the dist vac advance and see if you have vac there at idle.Hope this helps.Would seem if you had a fuel low supply would show when driving at high speed making it starve for fuel.That ignator may be failing when it gets hot but you would think it also would do it when driving.Hope this helps.

link9711
63 monza spyder
San antonio TX

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Re: Many of you have experienced this...
Date: September 10, 2022 09:13AM

Unsafe140 Wrote:
-------------------------------------------------------
> Sometimes I feel like im the last person still running mechanical fuel pump.
> I replaced pump 1 year ago just before I tore up the diff and had it rebuilt.
> Fuel pump has like 5 miles on it. Doesnt mean thats not the culprit.
> Plugs are all good.


I'm running the same mechanical for years now and its been absolutely fine... knock wood.

1961 Corvair 700 Sedan - 3sp - Gasoline Heat - Lowered a bit - Rust in Progress



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Re: Many of you have experienced this...
Posted by: joelsplace ()
Date: September 10, 2022 08:13PM

If it only has trouble idling and runs fine otherwise it isn't a weak fuel pump. It could be overpressure but I have no idea how much pressure a Holley needs or can handle. It sounds like some kind of hot soak issue. If you run it a while does the problem go away?

Joel
Northlake, TX
5 Ultravans, 138 Corvairs and counting...

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Re: Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 10, 2022 09:29PM

I hope to get to looking at it again more closely tomorrow
Thanks for all the leads

Joel
Cave Creek, AZ
1965 Corsa 140 tele

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Re: Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 15, 2022 07:27PM

Made sure the carb vacuum port was plugged well. Started right up ran good.
Drove ten miles. Idled in front of house for ten minutes. Drove to garage, went to back up to park and it died. Then acted just as before, tried to start revved up to 3k and died again. did that a couple times. Pushed it into parking spot and called it a night...weird

Joel
Cave Creek, AZ
1965 Corsa 140 tele

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Re: Many of you have experienced this...
Posted by: Brizo ()
Date: September 15, 2022 10:57PM

Did you test the fuel pump yet?

You never mentioned if it still has points or not? If so, it could be a bad condenser.

Dan Brizendine, Circle City Corvairs
'64 8 door Greenbrier, +.060, stroked 1/4", 186 ci.140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"



Edited 1 time(s). Last edit at 09/15/2022 10:58PM by Brizo.

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Re: Many of you have experienced this...
Posted by: Unsafe140 ()
Date: September 16, 2022 07:03AM

No I am not running points anymore.

I dont believe it to be the fuel pump as it was running good and idling fine
just a few minutes earlier.

I will have to keep investigating. Doesnt lead to confidence to drive outside the neighborhood.

Im not sure what it is but these little gremlins are no doubt more common
than sbc vehicles ive owned in the past (maybe this is what keeps prices depressed). I know some of you out there will argue thats not the case but the
anecdotal evidence seems overwhelming...

Joel
Cave Creek, AZ
1965 Corsa 140 tele

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Re: Many of you have experienced this...
Posted by: MtnVairMike ()
Date: September 16, 2022 08:19AM

corventure Dave Wrote:
-------------------------------------------------------
> Also may want to check voltage to the coil. Plus the coil may be failing. I have seen new off shore coils that overheat and fail almost right away. If the coil was exposed to too much voltage at one time, it could be an issue.
>
> Also be sure the fuel filter sock on the fuel sending unit in the tank is not encrusted and limiting fuel flow.
>
> Just another thing to check.
>
> Corventure Dave

I had that happen with a coil...

1966 Monza Convertible, 140HP-4 speed, Ermine White
1969 Monza Convertible, 110HP-PG, Frost Green

Black Mountain,NC

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