I have a '72 Plymouth 318 engine and am wondering if it is a non-interference engine if the timing should jump due to a worn nylon cam gear? I appreciate any info here. John
The valves wont hit the pistons but you might want to drop the oil pan and remove the pieces of cam gear if it is all off.
Why not get rid of the worry by putting on a 'new' timing set? If what you have is the original set, by now it probably needs it anyway!!
Any 318 I ever had that wiped out the chain was most definitely an interference motor! '57, '81 and '95, all bent the valves all to hell. If it just jumps a cog or two, no problem, but if it breaks, it's a wipeout.
I screwed up a lot of 318 in my younger days, it was a pretty tough job, but I stepped up to get it done. The ones that lost the timing chains only slipped a tooth or two. Never had one bend valves, but it could happen, there is a very limited few degrees of rotation where the valves can contact the pistons on a 318. The pistons are pretty far down in the hole, and by 72, Mopar dropped the compression even more. The only small block Mopar we ever bent valves on was the one where we broke a rod and the piston slammed the head hard enough to break the piston. Maybe I was lucky. Gene
The engine has about 44,000 miles on it. I never liked those nylon gears so a replacement set with a steel cam gear seems to be a good idea. Thanks for all the responses. John
If the cam was not turning and a stock 2 barrel cam has a lift of .373 intake a .400 exhaust chances are something got together. The same for mostV8s.
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