deaddds

Last weekend to get a car ready that had a poor carb job, I exchanged with another rebuilt, rebent basically correct lines and got the car fired up. Sounded good, ran out good- no detectable leaks. Next morning flushed radiator and changed generic U/L hoses with correct including clamps. Fired car up and topped off coolant as it idled when up to temp. Alll still looked good so took it out for a spin, ran like crap! Shifts crummy, sputters, made it around the block and back in garage before a wrench went through the windshield. Haven't had time to get back to it yet but can a trapped air pocket cause this? I'm thinking to look for a vacuum line that came off. Ideas? Thanks

rocketraider

How did the car run with the other carb?

4GC carbs can be persnickety. If they have the wrong gasket between float bowl and throttle plate they will do all kinds of hateful things, because wrong gasket can either create a vacuum leak, or plug a required vacuum bleed. They are also very sensitive to float level. A 16th inch off either direction can make one go crazy.

I fought with one on my blue Starfire for years till I finally said the hell with it and got a Holley Carb Shop reman. Bolted it up and car ran best it ever had.

The best running 4GC I ever had developed an unstoppable fuel leak at the inlet nut. There have been two different ones on that car since then, and they ran OK, but nothing like the original.

If it's shifting weirder than normal, make sure you didn't disturb any of the TV linkage when you changed it out. Also make sure the distributor vacuum advance is working and that its source port on the carb has a vacuum signal.

deaddds

Ran just fine once fired. I got a steel line from one of the big suppliers that list a 63 394 w air but surprise! doesn't come close. Honestly, where they get patterns is beyond me. So after having to reconfigure most of the bends, there were some crappy looking kinks so I was figuring it would be fuel starved. After cranking a few times to get fuel to the bowl and a shot of ether, it fired right up and idled fine. I watched this for a few minutes looking for any leaks, then drove it a few miles after the cold light went out. Performed fine, no hesitation, shifted normal. Put it away that day then returned in the AM to flush. Still idled smooth while playing with the coolant and when I was sure the stat opened and no more drop in fluid level, I closed the hood and tried to drive off. Then..... bad words.

fasteddi

im having the same problems with a 1962 olds 98... runs fine for 10 min then runs like crap..... whats the problem here?

dlh61olds

I had a brand new 1961 D-88 that did what you describe.

It turned out to be the sock on the fuel pickup in the tank was collapsing.

Let it sit 10 minutes ran O.K.

Start down the road and 10 minutes later, same thing.

Pulled into a dealer in Alb. N. M. , removed sock, no more problems.

I don't know how ethanol affects the socks but it probably is not good.

Good luck, Dave