Re: Idle problem
1978 should still be a distributor ignition engine. If the distributor is not moving freely, then several malfunctions can occur. If your engine is distributor ignition, then check two things:
1. Check the distributor body to see if the old grease has dried or hardened in it. remove the top pulley, first setting it to TDC for reference (curved line matches curve in flywheel--makes it easier to put back). Then remove the distributor cap. Now, on top of the distributor mount there is a snap ring holding the distributor to the mount. Remove it, remove the distributor and clean the dist. body and inside the mount. Re assemble and grease it--there is a zerk fitting on the side.
2: Be certain that the distributor belt is not too tight. Too tight, and it will not only keep the distributor from returning to idle, but it will cause hard shifting because of linkage interference.
Proper way to tighten the distributor belt is to loosen the two mounting bolts and just snug them. Now twist the mount until the belt is tight enough that a .010 feeler gauge pressed on the center of the belt (like a finger) deflects it 1/8 to 3/16 inch before it bends. Tighten both bolts.
