I drove my for the first time tonight since last winter. It was running fine when parked. Now it has several symptoms that I think are likely a stuck float, but I'd like to get more opinions. 1961 Chevrolet with a 327 and 4G Rochester. Symptoms: moderate (more than normal) white smoke in the garage even when only running for a short while. It doesn't obstruct vision, but has bad smell and can easily been seen in the correct lighting. engine tries to stall when coming to a stop at a stop sign or red light. I must brake with my left foot and feather the gas. Once stopped, it will idle, but if I just pull up to a stop sign/red light normally the engine tries to die. in the driveway, if I am rolling very slowly and hit the brakes hard, the car stumbles but typically picks back up and won't die. (possibly unrelated) intermittent bog upon acceleration 1/2 or more throttle or when stabbing the pedal. Slow acceleration has no bog. Thanks,
Most of the faults you listed are associated with incorrect mixture. Someone here will know the settings for that carb (I think its all the way in, and about 1-1/2 turns out then start it and tune for the sweet spot).
Does it have fresh gas or is it what was in it when you parked it? And, is that gas part ethanol or pure gas (if there really is such a thing anymore)? And, how long was it parked?
Ah,,,, motion has an effect. You say So find a tool not too heavy. ( pliers? ) It hibernated all winter, a couple, well placed raps, to the carb, may just finish the wake up. Or to your question yup, maybe
Do you have vacuum boosted brakes? Sounds like a bad booster suckin' air and brake fluid. Does it stall if it sits idling and you stomp on the brake pedal?
Thanks for the replies. It has gas from last year. It was non-ethanol gas (we have a local Pacific Pride dealer here and I have an account to get 100 percent gasoline. No power brakes or power anything at all. It's a 4 speed, so I can't really brake-torque it to get a reaction in that way. Last year I rebuilt the carb, went completely through it and all upon reinstalling I had all the settings correct and it was running good.
Doesn't sound like a stuck float to me, they seldom get stuck anyway, if anything there is a stuck float valve, but that would just turn your engine off. I guess it's the gas - try some fresh gas from a canister to make sure.
Another vote for fresh gasoline. Todays gasoline without ethanol still has other undesirable contents. Generally (not always), with stale gasoline, the symptoms will lessen after the engine is run for 30 minutes or so at a time (attaining normal operating temperature). My low compression John Deere won't even start on last years gasoline from cold. Start it on ether to a high idle, and run it at high idle until the engine is hot. Then it will restart (hot) on old gasoline. Jon
unlikely, white smoke could also be from a lean state, as i experienced while trying to meter fuel by hand on first startup.
100% gasoline just means no Ethanol is in it, but it’s not like it was “back in the day”. I remember being under my daily changing the fuel filter in the early 90’s, some gas came out and made a little puddle. It sorta mesmerized me watching it evaporate and just leave a stain. Heck, didn’t even smell like it did 20 years before that. The smoke aside (and I’m no expert) I think the carburetor needs proper cleaning. Since you feel the float is “stuck”, guess you’re going to pull the carburetor anyways and check it out. May as well keep on going.
Carb settings don't change during idle storage time, so if it ran good prior to winter storage, it's more likely something is clogged up from gasoline going bad. I'd do the Sea Foam thing mentioned above, and get it out on the freeway at higher speed to let it do it's thing. If that doesn't clean it out, it may need to be torn down to clean it out. But I doubt it will need that.
Bad gas is a good guess. If you live with high humidity, the carb can ice up at certain temperatures with a cold engine. That will make it seem like it's flooding. Steam (white smoke) will be present at the tail pipe, too. If you let it idle for a while when first started , does it start acting like it's flooding and gets worse until it quits? Try adjusting the fast idle cam on the carb. If it idles slow when cold, it needs to speed up to get the manifold/carb warm enough to open the choke. After the carb is warm it should be okay. This used to be a common issue with carbureted engines. Doesn't happen with fuel injection. I put up with it constantly. Get some fresh gas...........
If I thought it was a stuck float, I'd be banging on the carb or taking it apart. White smoke could be a number of things from bad fuel, plugged carburetor orifice, to head gasket. You have some investigating to do.
Does it have an automatic transmission? And, Is it shifting strangely? I've had a vacuum modulator diaphram fail...very similar symptoms.
My son had a similar issue. It was too much fuel pressure. Those small Rochester 4G carbs don't like too much fuel pressure which acts like a stuck float. We put an adjustable fuel pressure regulator on it and dialed it down til it ran good. When you go buy a new fuel pump at the parts store, they sell you one that fits all small block Chevys and puts out 6-7 psi which is too much for those carbs.
Oh come on kids, just a little case of old gas with some condensation in it and the exhaust. No need to go condemning the modulator or transmission yet over it! Jeez!
I agree with SS327, if the tank wasn't full over the winter, there would have been room for condensation to form in there. When I was in the trade, we added a cup of methelated spirits to the gas to get rid of water.. In your case, I would drain the tank and add new, disconnect the fuel line to the carb and blow thru with air, and clean out the carby..
Top it up with fresh fuel and lead foot it down the freeway. Probably needs a good fang to clean it out instead of tooling around the city.
This is why I drive my car all winter, wards off evil spirits. If you have a 1/2 tank of more, pour in 1 pint of denatured alcohol, it will take care of any moisture in the fuel.
Bull Shit! I have been using it for years and never had any problems. Even in my lawn mower, and Snow blower.
Curious if @Vetteman61 has figured this problem out yet? Maybe you had a chance to mess with it over the weekend?
Oh geesh…….. I have a flathead that has been sitting for 4 years with that in its tank and I’m wanting to try and fire it up this week.
Mad Mike I hope you’re right, I just poked my nose in the filler tube and it smells like it’s still good but you never really know. My dad always put a new carburetor on after it sat for a really long time because he said it would varnish on the inside and sometimes a fuel pump (stock 8BA)
I prefer the Blue Marine Sta-Bil. I have seen problems with the red (very few) when I was in the golf kart business. But something is better than nothing with todays fuels!
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