In Reply to: Sputtering 9n posted by Michael K. on May 26, 2018 at 22:57:04:
You won't find better instructions on Carb adjustment than these from the archives posted by Bruce.
Posted by Bruce (VA) on June 06, 2010 at 09:13:06 [URL] [DELETE] :
In Reply to: carb adjustment posted by AL CT on June 06, 2010 at 08:02:22:
Unhook the rod to the governor.
Both Ford and Marvel/Schebler (assuming you have a M/S carb ) say to set both the side-pointing idlemix and the down-pointing mainjet to 1-turn as a starting point. I set the down-pointing mainjet to 1-1/2 turns and don't fool w/ it anymore.
Then adjust the side-pointing idlemix for fastest idle; not the smoothest idle. Next, adjust the behind the carb idle-speed set-screw for very slow 400-rpms idle. Do that idlemix adjust for maximum idle at least 3-times. Make sure that you turn the screws slowly, like 1/8 of a turn at a time & wait a second or two for the engine to catch up. Take your time!
Do it like this:
1. Adjust idle mix jet until RPM increases
2. Adjust idle-mix set screw until the engine nearly stops (as slow as you can get it unless you have a tach that tells you 400 rpm)
Repeat steps 1 - 3 three times.
Remember the side-pointing idlemix is out for lean, in for rich.
If you do not have any problems inside the carb, it is easy to get the idle down to 350 - 400 rpms.
Now hook the governor rod back up. If the engine speeds up, the rod is too short, so adjust the rod.