The Stovebolt Site Forums The Shop Area Engine Shop 55 235 sputter

Hi Guys, my engine starts to hesitate like its running out of gas until you mash down on the pedal then it picks up with good power until you let off the gas then it starts all over .The carb bowl is full of gas the fuel pump is new the coil is new ,just not sure if its fuel or electrical .Thanks

Look for vacuum leaks. Also, try setting the idle mixture for best idle, and set the idle speed up a little. The good power with acceleration eliminates many suspects, including most electrical troubles.

Harvester

Thanks Wrench Fetcher,I'll try that first thing tomorrow,I hope its something that simple, it does'nt do it all the time,Drove it 100 miles round trip to a car show this past Saturday and everything was great,not a problem . Drove about 3 miles today and it started doing it. Thanks again, Jim.

I tried to make the carb. more rich and raised the idle but its running terrible ,didnt help , I took the rochester apart but cant find anything obivious wrong , maybe it just needs a good soaking, any suggestions

can't find vacuum leaks by lookin inside the carb

Bill

Since you have it apart already, put a new gasket set in it. Replace the base to manifold gasket, too. Might also want to check the carb isolator for cracks. Other places to look for leaks are the manifold to head gaskets and the wiper vacuum supply hose, if equipped.
Another thing to check, just judging from the description of what it's doing, check the timing. You may need to advance it a bit.

Sorry I forgot to mention I didnt find a vacuum leak from the vacuum advance to the carb or the wiper hose.I'll replace the gaskets in the carb tomorrow .why does it smooth out when I add choke after its warmed up. Thanks for the help , Jim

That does sem to indicate vacuum leak. May need to replace the intake manifold gaskets.

as longbox sez, if using the choke smooths it out you've got a leak some place

Bill

Whats the best way to find a vacuum leak

Sounds like vacuum to me. But don't rule out point gap, timing, and or possible low voltage problems. The low voltage problem will feal like fuel starvation. This condition could be caused by an improperly adjusted voltage regulator along with a weak battery. It would correct itself when you accelerate due to the charging system working better at a higher engine RPM.