emsrescu

run on is too much timing. correct?

JB

Actually, it's my impression that run-on (deiseling) is most often caused by too high an idle speed and/or a carb fuel mixture that's not set right.

JB

bloodvette80

i had run-on until i advanced my timing. it went away. Also, i know carbon in the chambers builds up and glows red hot... as a deisel. try adding a little water into the carb with engine running, usually dissolves any carbon build up. if that doesn't work, start buying diesel at the gas station... can't beat em- join em. :cheers:

Fevre

Running a cooler plug cold also help if all other adj are right on (timing, idle speed, throttle positon, etc.) There is a thread on plugs that has a link to the AC delco site with info on telling how to decode the plugs numbers.

EDIT here is the link:

www.acdelco.com/html/pi_plugs_ident.htm


[Modified by Fevre, 10:41 AM 7/16/2003]

Jvette73

Run on is usually caused by carbon build up or too high of temp in combustion chamber. High combustion chamber temps can be caused by reterded ignition or retarded cam timing(worn timing chain), too high of heat range plugs, lean fuel mixture. what happens is after you shut off the ignition, something in the chamber, either casting bumps or carbon bits are still glowing red hot and providing an ignition source allowing the engine to run on. Start by changing to a colder plug, setting the ignition to specs, and making sure the engine is not overheating. I had a high mileage olds 350 once that would always run a bit hot and on. Eventually the timing chain went south and the car wouldnt start. after I put a new timing chain on it cool down and didnt run on any more.