I just picked up a 78 AMC with a 258. Has sat for 5 years, It has a bent pushrod ? I heard this engine likes to turn backwards at times and bends pushrods ? Why ? Thanks

Dear GM;

Sometimes the SMOG crap will cause
an engine to "snap backward" when
shut off.

In some; a valve can hit piston??
--------

You'll most likely find a bad timing
gear has caused this.

Good luck.

gmguy,
For what its worth a few years ago my son bought a '80 AMC Eagle with a 258. The car had sit for 3 years and after we got it started it had a miss. After replacing plugs and wires it still had a miss. Pulled the valve cover and found #3 cylinder
exhaust valve push rod was bent. It turned out the valve was stuck. A small brass hammer and a short bar along with some WD40
cured the problem.

Gordy

Dear Gordy;

Marvel Mystery Oil is a good
product for that as well.

The AMC six is not known to have inherent valve train problems. It's not "known to run backwards" though of course anything can go wrong with bad maintenance!

Stuck lifters and/or stuck valves from sitting and neglect are by far the most common source of this problem. Sitting for 5 years pretty much gaurentees that there is something wrong. Old oil is gaurenteed also to be no good.

thanks all !