GM Cutlass RWD 1970-1987 Repair Guide

Diesel Valve Lifter Bleed-Down


If the intake manifold or head has been removed, removal, disassembly, reassembly and bleed-down of the lifter will be necessary. This procedure requires the use of special tools not available to the general public. Therefore, we won't cover it here. If only the rocker arms have been removed. or loosened, the bleed-down procedure is much simpler, but still quite complicated. Proceed as follows:

  1. Before installing any removed rocker arms, rotate the engine crankshaft to a position of the No.1 cylinder being 32 degrees before top dead center. This is 2 inches counterclockwise from the 0 mark on the timing scale, measured along the rim of the pulley. If only a right side rocker arm was loosened or removed, remove the No.1 cylinder glow plug to determine if the position of the piston is correct. Compression pressure as the piston rises will assure that you're right.
  3. If a left side rocker arm was loosened or removed, rotate the crankshaft until the No.5 cylinder intake valve pushrod ball is 7mm (0.28") above the No.5 cylinder exhaust valve pushrod ball.

Use only hand wrenches to torque the rocker pivot balls.

  1. If removed, install the No.5 cylinder pivot and rocker arms. Torque the bolts alternately between the intake and exhaust valves until the valve begins to open, then stop!
  3. Install the rest of the rocker arms, except the No.3 exhaust valve, if removed.
  5. If removed, install, but do not torque, the No.3 valve pivots beyond the point at which the valve would be fully open. This point is indicated by a strong resistance while still turning the pivot retaining bolts. If you go beyond this point, the pushrods will be bent. Torque the bolts SLOWLY to allow the lifter to bleed down.
  7. Torque the No.5 cylinder pivot bolt slowly. Do not go beyond the point at which the valve would be fully open. This is indicated as described above.

Do not turn the crankshaft for 45 minutes after the above procedure has been completed.

  1. Finish assembling the engine.