GM-GMC: Motor overheated after tune up, blown head gasket, computer command control

Question
Dear sir: I took my 1987 GMC pickup to a local mechanic for a tune up. When I got my pickup back it ran hot on the way home. I took it back to the mechanic shop. They said it had a blown head gasket. I have owned the pickup for five years & it has never ran hot. I drive it every day to work & back . About 20 to 22 miles everyday. Never has it over heated. The mechanic said that moving the distributor timing would not make it run hot. This was part of the tuneup procedure.My question is. If the timing is to far advanced or retarted will this cause the engine to overheat and cause possible damage?   Thank You John DeWitt

Answer
If the ignition timing was severely advanced, it could cause the engine to overheat.

However, the engine should have been "pinging" anytime it was placed under a load, indicating the timing was too far advanced.

In addition, GM used Computer Command Control on mid-1980s GM engines and, with its sensors, CCC should have automatically controlled the timing so that it was within the proper range.  Which leads to the question: Why did the distributor have to be moved?

You may wish to get a second opinion at another shop.