Repair Pontiac Mid-size 1974-1983 Repair Guide

Timing Gears



151 Four and 250 Inline Six Cylinder Engines

The camshaft in these engines is gear-driven, unlike the chain-driven cams in V6s and V8s. The removal of the timing gear requires removal of the camshaft.

  1. After the cam is removed, place the camshaft and gear in an arbor press and remove the gear from the cam. Many well-equipped machine shops have this piece of equipment if you need the gear pressed off.
  3. Installation is in the reverse order of removal. The clearance between the camshaft and the thrust plate should be 0.001-0.005 in. on both engines. If less than 0.0015 in. clearance exists, the spacer ring should be replaced. If more than 0.005 in. clearance, the thrust plate should be replaced.