found the gas leak on my carb

[SMKN97GP]

so gas is leaking from where the fuelfilter/fuel line enter the carb. i guess thats a common problem on the quadrajets. only problem is those fittings are on there sooo tight. i dont have a line wrench that is the correct size so i have to get that. my friend says he has the wrenches and hes done it before so i should get it fixed this weekend. now if its a steady but semi slow drip at idle, do you think that would be the reason for the engine choking out when i rev it...not getting the fuel because its leaking out. also anyone else ever have this problem> is there a gasket in there i should replace.

 

[tonyk72]

It's a common problem on the Holley's too...could possibly be a very dangerous situation...Maybe the fuel fitting and/or threads are damaged? Check those. Next, make sure you use a flare wrench & use the right size. I got the 9 piece Craftsman flare wrench set for $39 from sears.com. It will save you much frustration & you won't be stripping any nuts.

In the end, if you still have a leak...& this is a bubba fix,but this is what I had to resort to...apply some pipe dope with teflon on the fuel fittings. This worked for me.

 

[ed_in_pa]

If it's the same as a 76, there is a gasket.

 

[SMKN97GP]

so would you agree that this is problably the reason why the engine gets angry when i give it some throttle?

 

[curtis]

Here's my 2 cents. A small leak willnot be enough to starve a revving engine. If choking out ie flooding, maybe your secondaries are opening too soon. If stumbles when you punch it, maybe the accelerator pump is not pushing in enough fuel. Be sure you put in a new filter in quadrajet a plugged one doesn't look much different than a new one. Any other fuel filters should also be changed. That gasket looks like a small flat donut almost like a piece of hard cardboard and very thin.

 

[brusso]

Take a trip to the local parts store and find the "HELP" turnstile. On it you should find GM carb gaskets. In it you'll find the correct one for the fuel filter housing.

 

[mike weyman]

upon hard accelleration the leak will suck air into the lines as the carb is calling for more gas.and it draws from the line.,wich creates negative pressure,wich will suck air into the line.mike

 

[SMKN97GP]

Take a trip to the local parts store and find the "HELP" turnstile. On it you should find GM carb gaskets. In it you'll find the correct one for the fuel filter housing.

i work at a small local parts store part time and i think we actually have that, if not i know the local autozone or maybe its an advance has a very large section of help/motormite. ill make sure to pick up one of those. thanks

upon hard accelleration the leak will suck air into the lines as the carb is calling for more gas.and it draws from the line.,wich creates negative pressure,wich will suck air into the line.mike

this is making sense to me. thanks for all the help guys.

 

[SMKN97GP]

two more questions


how tight are those fuel fittings screwed on!?
and what size is the smaller fitting? it looked like 5/8th so i picked up a 5/8th line wrench at work...and it went on there snug, and i applied alot of pressure up until i was applying my full force and the thing wouldnt budge...the wrench actually started to slip off and strip the fuel line fittingad

these arent a reverse thread or metric or anything right?

 

[Vettehead Mikey]

upon hard accelleration the leak will suck air into the lines as the carb is calling for more gas.and it draws from the line.,wich creates negative pressure,wich will suck air into the line.mike

The pressure in the line would have to drop below atmospheric to allow any 'sucking' affect. The fuel pump constantly supplies approx 5 psi under all conditions. If the pressure/flow were to drop below demand from the float bowl, there would still be no 'sucking affect' as the bowl operates at atmospheric pressure.

The principle of operation is no different than the tank on a toilet- float drops, valve opens, water flows in at domestic water pressure. Tank is vented to atmosphere. There's no condition where the tank can suck air into the line.

 

[SMKN97GP]

i finally got it off!! replaced the fuel filter... i think it might of been the original . things were sorta gunked up in there. anyway i put in the new filter, cleaned out the area and put in the gasket and there was no more drip drip . and when i revved her up there was no staling, or choking or poping like before. the big test will be tomorrow when i take her down the road for a rip. hopefully all will go well. then all i gotta do is take it over to my buddys shop one of these days, fix the flexplate and ill be all ready for a corvette summer