The Stovebolt Site Forums The Shop Area Engine Shop Fuel Problems/ Carb HELP

Ok, Here it is. Truck cranks and runs but a little rough unless I leave the choke pulled out a little bit. drive 10-15 or however many miles. Sometimes at idle I have to pull the choke out a little farther so it wont die then back in when moving. As SOON as I get to where I am going, if I turn the truck off then immediatley try to crank it again it only turns over but no go. I found that if I take the top of the carb off, then replace it. It will start after I crank and crank with my foot holding down the gas pedal like when its flooded. Please help me with this problem. The carb was rebuilt by my Father in Law and I think we are going to do anther rebuild. The needle does appear to tick sometimes. But I just dont know. A year ago I had never even seen the inside of a carb. So bare with me. Thanks

Running with the choke pulled out for very long (like 5 miles)makes the fuel-air mixture too rich. The result can be fouled plugs. If the plugs get fouled (dirty, black carbon buildup on the electrode) the engine can be hard to start and rough running.

Distributor wear on the points and cap, as well as adjustment on the vacuum advance, can cause hard starting and rough running, although fiddlin' with the choke won't usually help here.

If your truck acts like the carburetor is flooding, I would be surprised (but I am often surprised by old Chevys) that taking the carb. top off and putting it back on would do for the quickest fix.

We need some others to weigh in here--somebody who's had a bunch o' trouble in the carburetor, ignition, timing ballpark.

C'mon you hawnyocks. Somebody out there knows what to do. Lay you ceegar down, putt yer beer bottle on the floor and get out here to the truck and help!

Sounds like the carb is running rich and needs to be adjusted, had the same problem with mine I just got my pops to help me adjust it and runs fine but also need to replace the advance vacuum.Someone else might have a better answer but thats what it sounds like. Good luck dude!

How much fuel is in the base of the carb when you pull the top off?

When it runs after warm up, is OK or just getting by?

When you get it warmed up and where it can idle by it self, get a 3 foot long small hose and use it to listen for any vacuum leaks under the carburtor. One end in your ear, the other poking around under the carb.

Are all the vacuum lines hooked up? Plug each line one at a time to check for correct opperation.

When you drive it, does it smoke? black or blue color?

You say when it restarts after the carb top is off you have to hold it to the floor or are you pumping it alot? First way is to much fuel, second way is not enough.

We need as much information as you can give. Joe

Have you checked for correct fuel pressure after your pump?

ok Here is what I would do. Pull the plugs and take a look. Probably need to replace because the are fouled. The colot of the spark plugs will tell you a lot. Then once plugs are replaced check the points and the points gap (probably fine). Next check the timing. Once you have done all that I would suggest geting out your vaccuum gauge and tack/dwell meter then your shop manual and start adjusting the carb.

Elimanate all the other possiblities first. Such as plugs points and timing then head back to the carb.

Now just for your records. This is my starting proceedure. If the truck has not been run for a day. Pull choke out, pump gas pedal 3 times hit starter button. This ususally works for me on the first try and for sure on the second. However once my truck warms up I push the choke in and run it. For starting the truck once she has been run. I eleminat the choke and just hit the gas three times and then the starter pedal.

Hope this helps! Let us know how things go.

You probably need a good rebuild on the carb. Get a porfessionally rebuilt one, but don't send yours as a core. get a swap meet $5 special and then learn again on your original. Sounds like the accelerator pump is allowing too much fuel in. Mine did the same thing. You should see it now.

Results of a night in the garage.

I have two of just about evrything since the newly rebuilt 235 was installed. I rebuilt the carb off the 216 and put it on the truck and she started right up. I then drove it around and didnt have to use the choke. She ran smooth but I think I may need to replace the plugs, idles a little rough. I think it was the needle valve that was hanging up. If I pushed the float in the up position, the needle would go up and then when I let the float go, the needle would stay in the valve until I shook it and then it would fall back down about half way. Anyway, Thanks for all your help.

That makes since, you had to pull the top off and doing so the float would break free all the while you never new it was stuck! Glad to hear its running. It sure fells good to get problems like that solved. Joe