Puddles of gas on my intake manifold

73 New Yorker

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Started my car and backed it out of my garage to let it idle/warm up. I usually pump it twice, start it, put it in reverse and it backs without me having to push on the gas pedal.

It usually idles high so I give it a light tap to kick the idle down. I did all this today and then smelled gas. I turned the car off, popped the hood and this is what I found. Pools of gas on either side of the manifold, mostly on the passenger side. All of this happened in less than three minutes.

I had the intake manifold and carburetor installed last June and have had an occasional pop/backfire if I try to step on the gas too quickly but never any gas leaks. 99% of the time the car has run great.

If any anyone has any suggestions I would appreciate the help. Thanks

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How tight are the fuel line clamps? Is that wetness I see around them? Have the rubber fuel lines a the rear of the stubframe and into and out of the fuel pump been changed, too?

Any fuel in the oil? Might be sure all of the fuel in the heat crossover part of the cyl head has fully evaporated.

Which carb?

Just some thoughts,
CBODY67
 
G'Day,
Please Allow Me to Make a Suggestion!
I Note That You Appear to Have a Paper Air Filter Element.
I Had a Very Nasty Incident with One of Those.
It's a Long Tale so I Won't Go into Too Many Details.
But I Had a Power Steer Hose Burst & Spray Hot Oil on to the Exhaust Manifold.
In the Ensuing Fire the Paper Element Caught Alight.
Was Fortunate to Get the Fire Out But What Didn't Help at All was the Fact That the Paper Element
Kept Smoldering and Reigniting Even After the Initial Quenching.
Since That Day, I Don't Run Open Element Air Cleaners or Paper Filters.
Just a Suggestion.
Kind Regards, Tony.M
 
Are your rubber fuel lines fuel injection rated? If not, I recommend switching over as today’s gasoline will eat away at the standard rubber fuel line hose.
 
Started my car and backed it out of my garage to let it idle/warm up. I usually pump it twice, start it, put it in reverse and it backs without me having to push on the gas pedal.

It usually idles high so I give it a light tap to kick the idle down. I did all this today and then smelled gas. I turned the car off, popped the hood and this is what I found. Pools of gas on either side of the manifold, mostly on the passenger side. All of this happened in less than three minutes.

I had the intake manifold and carburetor installed last June and have had an occasional pop/backfire if I try to step on the gas too quickly but never any gas leaks. 99% of the time the car has run great.

If any anyone has any suggestions I would appreciate the help. Thanks

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What carb are you running? I don't like the looks of that transmission linkage adjustment either. Just sayin.
 
Holley 750 and yes the transmission linkage is going to be dealt with this summer.
I would inspect your Holley closely. There are a lot of places where they can leak gas. You did mention backfires. The power valves can blow out and cause rich running as well. The transmission kickdown can cause transmission failure in short order if not adjusted properly.
 
Hi Just a guess but your carb could be percolating. (Scenario)You take your car for a good drive etc. You park your car , the heat in the engine will build up in the block before it starts to cool , this is called "heat soak". If you've ever watched your temp gauge after restarting, say after a fuel or Burger stop you will see the gauge climb to above middle and then as the engine runs the gauge will start to drop to normal . That's what heat soak looks like and why most modern cars use a coolant reserve tank on the radiator.
I see you have a thin carb base gasket , your aluminum intake manifold is a very good conductor of heat , the carburetor will absorb this heat and the fuel in the bowl will start to boil , sometimes to a point where the fuel will get pushed back out of the bowl vent ,or even out of the idle air bleed holes in the air horn and if severe enough out onto the intake manifold. The common remedy for this is a bakelite carb insulator installed on the base of the carb usually about 1/4" to 1/2" thick gasketed on the top and bottom. The bakelite insulator controls the heat transfer.
 
Turns out the fuel filter had come partially unscrewed. Tightened the filter and the hose clamps at each end, problem solved.
And with all the responses I got I now have about a dozen other things I know to check next time. The people on this website are one of the best parts of owning a C-body.
Thanks from a newb.
 
Turns out the fuel filter had come partially unscrewed. Tightened the filter and the hose clamps at each end, problem solved.
And with all the responses I got I now have about a dozen other things I know to check next time. The people on this website are one of the best parts of owning a C-body.
Thanks from a newb.
You need to toss that junk filter over your shoulder and replace it with something that doesn't unscrew or crack.
 
Turns out the fuel filter had come partially unscrewed. Tightened the filter and the hose clamps at each end, problem solved.
And with all the responses I got I now have about a dozen other things I know to check next time. The people on this website are one of the best parts of owning a C-body.
Thanks from a newb.
Good to hear you figured it out.
 
"The people on this website are one of the best parts of owning a C-body.
Thanks from a newb."
You Forgot to Mention That We're Good Looking Too! LOL
Regards Tony.M
 
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