fuel starvation/vapor lock?

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bajaroadster
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fuel starvation/vapor lock?

Post by bajaroadster »

Replaced fuel filter recently and noticed that the gasket looked very well worn.(original glass bowl set up) Put it all back together until I could get a new gasket. Car ran fine for several weeks. This morning I started the car, again it ran trouble free. Removed glass bowl and old gasket and replaced the gasket with rubberized cork gasket and reassembled. Car started right up and ran for about ten seconds , then started to sputter and finally died. Classic fuel starvation symptoms. Now car will not start. I searched site for similar posts to no avail. Suggestions?
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Re: fuel starvation/vapor lock?

Post by bossbob »

Is the glass bowl filling up? I would start by pulling the line off the fuel pump, crank the motor and see if you are pumping fuel?
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Re: fuel starvation/vapor lock?

Post by notoptoy »

Put a light coating of grease on the gasket and try again. If all you did was remove the fuel filter bowl and reinstall, you had to create a small air leak.
If you did not touch anything else, I'd bet that is it.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

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bajaroadster
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Re: fuel starvation/vapor lock?

Post by bajaroadster »

I'll try the coating of grease today and hope that solves the problem. I have had the glass bowl off before without incident. The only difference this time is that I replaced the gasket. Did nothing else on the car that day. It would be a huge coincidence that the fuel pump would fail at just that moment, but ive had stranger things happen over the years. I'll also check by pulling the line at the fuel pump as suggested to be sure. Thanks for the advice, we'll see what happens.
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Re: fuel starvation/vapor lock?

Post by redroadster »

HF makes a hand operated vacuum pump with a catch bowl. $ 20. Thats Aweful handy
If it doesnt bring gas up in 3-4 quick pumps
bet your pulling the tank
What year? My 70 had a S bend that with calcium inside gives only about a 8th " line
I cut out , found a cheap sock filter for the tank
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Re: fuel starvation/vapor lock?

Post by bajaroadster »

Thanks to notoptoy for the simple fix. Pulled the whole filter assembly out of car instead of just dropping the glass bowl.Did some very slight trimming of the gasket to fit better, light coating of grease, fill bowl half way, and made sure bowl was centered perfectly. After a few turns of the key, car fired and ran without further problems.
Redroadster, my car is a 67 1/2. Thanks for the info on the vacuum pump. Sounds like a helpful tool to have around.
Bossbob , thanks for the input , that's why I love this site. All are willing to help. Now instead of stressing all day about a solution , I was able to resolve the issue and can enjoy the car and the day.
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Re: fuel starvation/vapor lock?

Post by notoptoy »

Excellent, congratulations on a simple fix!
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

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Re: fuel starvation/vapor lock?

Post by 23yrRebuild »

FYI....I use this rubber gasket for the glass bowl fuel strainer in my '67 1600/stroker:
https://www.oreillyauto.com/detail/b/sp ... 08/4722181
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Re: fuel starvation/vapor lock?

Post by bajaroadster »

Car has been running well with the exception of a stumble when it is a hot day and the car is at operating temp for several miles. Stumble occurs after stop signs or when the rpm's have gone down to an idle. Also, occurs if I turn the car off briefly and then restart within a few minutes if the car is still at upper operating temps when I return. Stumble will last about 20 seconds until rpm's are raised and then smooths out and runs well. The last time this problem occured , I took Notoptoys advice and put a thin film of grease on my cork gasket on the glass bowl fuel filter assembly and it solved the stumble. Apparently a slight air leak at the glass bowl gasket. Since the problem returned I assumed it was the same problem with the cork gasket drying out and purchased a roll of rubberized fiber gasket material and some permatex gasket dressing & sealant, hoping that it would be a more permanant fix than the cork gasket used before. Dressed the fabricated gasket with the permatex and installed. I had pre filled the glass bowl with fuel and the car started right up, but stopped running shortly after when the fuel in the glass bowl was used up. The system is not drawing fuel from the tank to refill the bowl. Is it possible that I created an air lock in the fuel line from the tank when I disconnected the incoming line to the fuel filter assembly? Am I correct in assuming that the fuel pump is not the problem since the car will start and run if I manually fill the glass bowl? Or maybe, ive just got a bad install on my new gasket and Im sucking air. Suggestions on how to best proceed appreciated.
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Re: fuel starvation/vapor lock?

Post by notoptoy »

Check the rubber hoses on the fuel lines, if any signs of cracking replace them.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

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Re: fuel starvation/vapor lock?

Post by Linda »

Get a clean cloth and put it over the disconnected fuel hose at the filter and blow back towards the tank. Notice any resistance, and listen carefully for the sound of bubbling. If there was resistance plus silence , then bubbling, you had a clog in the tank which you dislodged....
I would get rid of the glass bowl filter except for car shows and get a regular modern filter.
Otherwise for the glass bowl filter gasket, try dunking the whole thing in the gas, blot it, then reinstall. It will plump up and seal. Always worked for me on my previous 67.
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Re: fuel starvation/vapor lock?

Post by notoptoy »

Other than the seal leak only one time and easily fixed, I've never had a problem with the glass bowl filter and it's been 20 years. I see no need to get rid of it!
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

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Re: fuel starvation/vapor lock?

Post by bajaroadster »

I think I will buy a generic in line filter and install it just as a process of elimination experiment. Funny how these simple projects always seem to turn into more. A fuel filter gasket update suddenly disables my car. (SIGH) Although im sure it will turn out to be an easy , affordable fix, In the moment, when a 30 minute fix turns into a project, it frustrates the heck outa me. But........silver lining. Plenty of cold brewskies in the fridge.
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Re: fuel starvation/vapor lock?

Post by DAC21 »

bajaroadster wrote: Wed Nov 11, 2020 7:21 pm I think I will buy a generic in line filter and install it just as a process of elimination experiment. Funny how these simple projects always seem to turn into more. A fuel filter gasket update suddenly disables my car. (SIGH) Although im sure it will turn out to be an easy , affordable fix, In the moment, when a 30 minute fix turns into a project, it frustrates the heck outa me. But........silver lining. Plenty of cold brewskies in the fridge.

Here you go for a replacement Glass filter main gasket. I'm not sure if you have an O'Reily s in BC? Grab a few at this price. Or try to cross reference to local auto stores in Baja. Thanks to 23yrRebuild for this info.

https://www.oreillyauto.com/detail/b/sp ... 08/4722181
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Re: fuel starvation/vapor lock?

Post by bajaroadster »

Thanks Dac. No O'Reily s but an Autozone. Maybe a cross reference.
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