Quote:
Originally Posted by Sparta
Hey guys! I’ve got a bone stock 1931 ford model A. It has a rebuilt engine with steel valves and bearings instead of Babbits. I just out on a rebuilt carb trying to solve the issue, which solved my backfiring issue, but car is still sluggish. The previous owner mentioned that the timing was off and that he fixed it before selling me it. The idle isn’t very steady, meaning it has intermittent hesitations when idling. Other than that, what else could it be? Could timing being alittle off cause the car to top out at 40?
Thanks
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Yes on timing as likely the problem.
Timing the Model A is a little bit of and "acquired skill." Primary to remember is keeping the engine motion "forward" always to take up any lost motion in the moving parts.
From your descriptor, I take it you haven't had the pleasure yet? You really should. Follow the directions which appear in several placed on the Internet, and in several books.
After you get the engine to what you think is "the magic spot," (top dead center) and have moved and fastened your cam, a check you can make is to use the spark advance lever. With the ignition ON move the advance lever to the fully advanced condition (lever all the way to to the bottom.) THEN without having moved anything in the engine, move the spark advance lever up to the fully retarded position. As you near the top of travel in a quiet garage you should hear the points open and the sound of the spark. The closer you can get this to happen at the fully retarded (top) position, the closer you are to correct timing.
Having someone hold a screwdriver on the distributor cam in the direction of rotation (CCW) will help make this check consistent - there is some tendency for the motion of the points traveling around the cam to pull it slightly and introduce lost motion. Not too tight on the screwdriver lest it undo the distributor cam screw.
Anyway, give timing a whirl. It's not that hard.
Joe K
(I have done this check myself by moving the connector lever on the side of the distributor rather than at the steering column. But two people can do it if one is at the driver's seat.)