Genuine 1989 Chevrolet Metro Cylinder Head

1989 Chevrolet Metro Cylinder Head Parts Questions & Experts Answers

• Q:

  How should the Cylinder Head be prepared and reassembled after valve servicing on 1989 Chevrolet Metro?

  Posted by Ryo S.

  A:

  Always clean the head before rebuilding it, whether you brought it back from an auto mechanic or not. When the head was taken for valve work, all required parts were attached to it before the shop returned it. Put each new seal in carefully until it fully joins to its guide, without twisting or spinning while doing so. Begin at the head's end, put moly-base grease or clean engine oil on the valve stem, and place the first valve in position. Set the valve spring and retainer on the guide, while holding a spring seat or shims on top. With a valve spring compressor, squeeze down on the springs, then slide the keepers into their slots along the grooves. Ease off the compressor while checking that the keepers are properly seated. Add a small grease drop to each keeper as needed. Setup each valve the same way, making sure you replace everything in the correct spot without any mix-up. Measure the valve spring height with an interval of 1/32-inch on a ruler or dial caliper after installing them; if a professional serviced the head, check to be sure the installation was correct. Before starting, measure from the spring seat top to the retainer bottom; if they're too high per specifications, install shims under the springs until right, but never go below allowed minimum. Before putting the lifters and camshaft on Metro cars, replace the distributor case by installing a fresh O-ring.

  Answered by GM Parts Specialist Nicholas / Jan 16, 2025