I've noticed that my car is difficult to start after it sits a few days. I replaced the carb with a rebuilt unit some time ago, but it seems all the fuel disappears from the fuel bowl if it sits for awhile. I have to grind on the starter, in short bursts, to re-prime the bowl, but once the fuel pump gets the fuel back up to the carb it will start and run fine. The car sits level so I don't think the fuel line from the tank to the pump is losing it's prime, but I'm suspicious of the fuel pump itself. Shouldn't there be a check valve to keep this from happening?
I had the same problem. After resetting the timing, new plugs , wires, and a new battery; it cranks up real good. Unless it's been sitting so long the fuel has evaporated from the carburetor.
Crappy gas and hot temps do wonders. My first guess is evaporation. the new blends aren't as efficient as the old blends so it takes more fuel to run an engine than it used to. That means the amount of evaporation that used to be considered acceptable is now going to cause issues.
your fuel pump is fine... all of my non-daily-driver old cars are like this. Instead of cranking the starter, I pump the gas pedal a few times before turning the key... starts right up lickity split :TU: Jeff ~
Another possible issue worth checking is the heat riser on the right exhaust. If it is stuck closed, the intake manifold will run hotter then it's design temperature and can cause excessive fuel evaporation from the carburetor.
I have an old parts car that runs, and it sits for months sometimes before I run it, so when I do I always spray starter fluid down the carb and make sure the choke is closed, then I hit the starter with foot off of gas pedal. Usually runs a second or two. I repeat the process until the fuel has made it's way back to the carb bowl, then it usually stays lit. This avoids endless cranking you'd have to do if just relying on the mech. fuel pump to recharge the lines and bowl just on the starter. I guess those old slick 50 commercials made an impression on me- I hate the endless cranking, especially since the oil pump needs to catch up too since all the oil is in the pan from sitting so long an bearings are unprotected. Kevin
Ithink it's mostly the modern gas thing, besides being more volitile than older gas was, carburetted cars generally have more difficulty with evaporation that's a result of it than modern fuel injected ones. Both of my old cars have new fuel pumps in them, and will be a bit finicky to start after sitting for a few days. If they run within 24 hours there's no problem, they fire right up.
I have the same issue with my 62 special. after a week of sitting, it needs to be cranked good to start up but on daily usage, it starts right up the first time.
I think we are goin to have to put electric pumps on them. The one I have a Qjet on I rebuilt and sealed the well plugs and even after sitting in the garage for a while you have to crank it alot. The one with a 2 barrel starts a little faster. Im wondering if the mechanical pumps might be letting the fuel run back to the tank. I pinched off the return hose and it still cranked a little after a couple of days. I dont run them long so the fuel cant be getting hot. Im running cam 2 fuel in them.
Thanks guys, you've given me a lot of ideas. I'm 60 years old and have owned and driven many carb equipped cars. Of course there were times when a car had to sit for awhile, but I don't recall it being this difficult to start them. Perhaps having to fill the fuel bowl back up, but it never took this long. Here is my plan. I want to put a fuel shut-off valve inline between the carb and the fuel pump and shut the valve off after driving. Wait a week and see if the fuel bowl is empty. That will give me a good idea if the gas is evaporating or leaking back down. I'll post back once I have the results.
Never got the chance to try my plan. The car has been sitting out at my daughter's place for a few weeks now, she needed my garage for a garage sale. I went out to get the car this afternoon after they had finally cleaned up the mess in my garage, but it would not start. It's my belief that the fuel pump is the problem as it is just too weak to pump the fuel up to the carb. I've suspected this ever since I got the car as it sat for a good long time (at least 5 years) before I got it. We had to use a siphon pump to get the fuel up to the pump originally, so even then I knew it was weak. I have one ordered and hopefully it won't take too long to get here. First time ordering from Auto Part Warehouse, hope they are okay. Could not find it at NAPA, was sure they would have it.
New pump arrived today and has been installed. Output didn't match the old one so some extra plumbing had to be installed. Found what I needed at NAPA and now the job is finished and the car started after about 5 rounds of short grinds on the starter. It never started that quickly before after sitting a long time so I think my problem all along was the old fuel pump. Will know more after it sits awhile. :beer
Please let us know if that helps fix the prob. I have the same problem, my 442 can sit for 6 months and starts right up, but the GS seems to lose fuel even though the carb has been rebuilt, well plugs done, etc.
<samp> "Use a small funnel with an inner diameter of 3/8" and place it over the float bowl vent tube and pour some gas into the bowl. You will save wear and tear on the starter and engine." (from helpful tips on buick performance club website) </samp>
Well, it has been over 2 weeks since I last started the car, so I pumped the gas a couple of times and hit the key. It almost started that time, so I pumped the gas a couple more shots and tried again. No go. Figured the third time is a charm and pumped it again, this time it fired right up. I believe the fuel pump was the problem. I also noticed that the clear glass bowl on the filter was completely full this time. Previously it would only be about half full after sitting for awhile. I also plan to change my oil and filter as some of the gas which leaked down may have found it's way into the crankcase via a bad fuel pump diaphragm. I've checked the oil level and it's not overly full, but better to be safe than sorry! :eek2:
