[JRHAWK9]

Hi guys, I have a '73 Pontiac 400 (out of a '73 Grand Am) in my '77 Olds Cutlass and ever since I took it out of storage after 5 years the car seems to lose it's fuel in the line and takes forever to start after sitting for more than a few days. If it sits for too long I normally have to dump a little gas in the carb in order to get it to start and to feed itself. Once the gas gets up to the carb it pops right off and goes to high idle and runs great. This was NEVER an issue before it sat for the 5 years. I just have the stock 2bbl Rochestor carb on it and the engine is 100% stock. Is there some kind of check valve in the fuel pump that could be dried up allowing the fuel to drain back to the tank....??? What do you guys think could be the issue?

thanks!
Paul

[BVR421]

Paul, given the gas formulation we have now, it sounds totally normal to need a primer shot of gas to start after sitting for a few days. What are a few dAys? 5? 10? The 2 barrel doesnt have a large reserve and todays gas evapoorates VERY fast.
I have 3 cars that are driven seldom anymore sometimes a month or two before starting again. I use a small plastic mustard bottle of gas to prime them. The pointy nozzle drops right in the float bowl vent and a gentle squeeze fills the bowl.
My cars and probably yours would start if cranked long enough but the primer is sure quicker.
Another thing to check is any rubber hose from tank to carb, A small crack or loose clamp can suck air and loose prime especially the short rubber hose between the tank and the metal line com9ing to the front or the rubber line from metal pipe to the fuel pump. Todays gas rots the old style rubber lines and they need to be replaced with modern fuel hose anyway.

[b-man]

These days what passes for gasoline evaporates very quickly, add that to the very small float bowl of a Q-jet carb (I assume) and you end up the common problem of keeping enough fuel in the carb to start the engine.

Sure-cure is to intall a small electric pump back at the tank to act as a pusher to work in unision with your mechanical fuel pump.

Chepest cure is to just pop the hood and prime the carb with gas, squirt it into the bowl vent tube to fill the float bowl instead of right down into the carb throat.

Today's fuels suck.

[JRHAWK9]

thanks guys!!

Originally Posted by BVR421

What are a few dAys? 5? 10?

this last time was 6 days. The thing is though, did the gas really change that much in the past 10 years or so?? Back before it got stored for a long period of time the car could go a whole winter and then fire right up in spring with no priming needed.

Originally Posted by BVR421

I use a small plastic mustard bottle of gas to prime them. The pointy nozzle drops right in the float bowl vent and a gentle squeeze fills the bowl.

where is the float bowl vent on my Rochester 2BBL? That sounds like a quick and easy way to prime it.

Originally Posted by BVR421

My cars and probably yours would start if cranked long enough but the primer is sure quicker.

yep, mine will start, but it just takes a while of cranking it over until it pops off. When it pops off it runs 100% normally like it should.

Originally Posted by BVR421

Another thing to check is any rubber hose from tank to carb, A small crack or loose clamp can suck air and loose prime especially the short rubber hose between the tank and the metal line com9ing to the front or the rubber line from metal pipe to the fuel pump. Todays gas rots the old style rubber lines and they need to be replaced with modern fuel hose anyway.

I have already replaced the ones in front going from the metal line to the fuel pump and will be replacing the ones from the sending unit to the metal lines in the rear when I replace my tank in a few weeks. My front ones were all rotted to heck and I was amazed they were even able to transport any fuel without leaking.

[Schurkey]

Originally Posted by JRHAWK9

Is there some kind of check valve in the fuel pump that could be dried up allowing the fuel to drain back to the tank....???

Yes, fuel pump check valve(s) can go bad and allow fuel to drain back towards the tank. Often won't show up when testing the pump for volume and pressure, because the leakage is so small--that's why it takes days to drain the fuel lines.

This is usually worse with Q-jet carbs because the float bowl is so much smaller than the one on your 2-barrel. As soon as fuel leaks or evaporates out of the bowl, the float drops. The needle lifts off the seat, and the fuel in the fuel lines can start siphoning back to the tank.

A crutch for this problem is to install a fuel filter in the carb inlet that has a safety valve (rollover valve) in it. Available at NAPA or any "real" parts store. If the problem goes away, you need a new fuel pump.

I though today's fuel was LESS volatile than the gasoline from years ago. Shows how much I know.

[zippy]

Ya, todays gas evaporates so fast. It's made like that so that spills will evaporate, hopefully before getting into the water system and the ground too deep. That was the main reason I went to a Elec pump. Even with a new fuel pump, rebuilt carb with no leaking fuel wells, It would be a bear to start after 4 days sitting. Now, I let the key on for 10 sec before I hit the starter and Voila

[JRHAWK9]

well, seeing it was cheap and easy I swapped in a new fuel pump Sunday afternoon. I'm not too optimistic that it will solve anything but figured it wouldn't hurt seeing the one that was in there sat a long time w/o seeing any use.