72 cutlass, car sitting for 17 years.i put on a new timing chain and replaced the fuel pump. After a bunch of eruptions of gas from the carb I got the car runnin for about 20 min. I was just tinkering with it a few hours and went to check the oil and I pretty sure it smells like gas. Can it be a rings issue, I don't see how it can be from the fuel pump. I'm gonna do a compression test, any other ideas.

 

Why can't it be from the fuel pump?

- Eric

 

Well, sounds like it flooded enough times to seep into the crankcase. I don't know that for sure, but that is what it is sounding like. Change the oil and filter and try again before you spin a bearing.

 

X2 on that. That is most likely what happened. Happened to my friends 69' Chevelle. We changed the ignition and distributor. There was a lot of cranking and flooding. Before we tried starting it again we changed the oil and filter. It turns out the doofus had the number 1 plug wrong.....

 

X3. This is the most likely scenario, however don't rule out a bad fuel pump diaphragm either, given the age.

 

You don't mention which carb, but old Q-jets like to leak from those pesky well plugs on the bottom.
Pull the carb, and if the gasket is fuel soaked, spray some carb cleaner on them and liberal amounts of 2-part epoxy should be the cure.
Replace the gasket!

 

Sorry, but Qjet well plugs have really earned a bad rap for this. The leaking plugs only applies to the 1965-67 carbs that used the pressed-in sheet metal plugs (they look like tiny freeze plugs). Starting with the 1968 model year, all Qjets used spun-in thick aluminum plugs that do not leak. This is not the problem if the carb is the original 1972 carb.

 

Thanks for the advice, will change oil and pray.

 

Joe, what's your theory then on where all the fuel in the float bowl goes? Pretty much every Q-jet I've owned will be completely drained within 8 hours of parking it. I know some of it evaporates due to intake manifold heat. Is the rest leaking past the needle and seat?

 

That's a lot of fuel for eight hours.

Are you sure it's ALL gone, or is it just low?

Does the car smell like gas after a few hours?

I had a 2-Jet once that dripped gas out the throttle shaft fast enough to see it.
Ran fine, but smelled as soon as you stopped. I finally replaced it with a Q-Jet but I never did fix it.

- Eric

 

No gas smell, so it isn't leaking externally. And yes, it acts like it's completely empty.

Typical start after 8+ hours:
-- Fires instantly thanks to pump shot (to set choke) but immediately dies.
-- Crank for about 5 seconds to pump fuel into bowl, then fires and runs perfectly.

Temperature is definitely a factor. When it's cold out it takes more than 8 hours and there's usually enough left in the bowl. But let it sit 12 hours and it'll be empty.