hi, i have an issue with my 1996 volvo 850 non turbo. it skipped two teeth on timing and i was wondering if it is crucial? how can i check for damage? i shut it down once it ran irratically. it ran for a moment and i did not drive it. also, if i have to change head, what special tools would i need? i was told that there is a special tool that cost about $100.oo is this true.? should i just put a new timing belt on instead of changing head, or am i playing with fire for more damage? any suggestions? thanks much for any help possible. tips and advice are appreciated michael in

 

Reset the timing and see how it runs.

 

question is, WHY did it jump ?

Personally i would be replacing, belt, idlers, tensioner, water pump. anything to do with the t belts path.

Expensive yes, but whats it worth if the belt/tensioner fails fully ??????

 

+1 FOR SHAGINWAGON.... First fix the reson that contributed to the belt skipping the gear. Possibly, the tensioner has gone bad or the belt itself was old and broke few teeth or stretched. SO, replace the tensioner and the belt and try running the engine with corrected timing. If its running smooth or with minor missing (expected), just run it like that and it might recover over time. What i do is feed some engine oil thru the intake to give it little higher compression and carbon that helps sealing the valves better.

 

The Timing Belt in these cars is the one thing that always frightens me about them. That said, you make be ok. I would just replace everything like Shagin said. Worse case, you have to pull the head and have it rebuilt.

 

Agreed, just dont start it to test until you have that belt replaced. You may be alright but on the other hand you could potentially destroy your valves with one key stroke.

 

I fixed a subaru once where the left cam had jumped 3 teeth after an accident that caused part of the broken radiator support to go through the timing cover and hit the belt. (boxer engine, there's a left and a right head) The car came in actually making a mechanical knocking sound on that side of the engine. I was certain that a valve or 2 had to be bent... but I tried resetting the timing anyway. The noise went away, and the valves sealed fine. I found that the piston was JUUUST hitting one valve very lightly, enough to make noise, not enough to bend the valve. It the belt had jumped one more tooth, that head would have looked like a salad. now THAT is lucky.

My point? try it and see... these engines have even less clearance than the Subaru, but MAYBE you'll get lucky. And DEFINITELY replace everything timing- related.

 

That is beyond lucky. I would not think that would have happened in a million years.

 

WEll, I have ended up skipping 2 teeth on a Daihtsu turbo DIESEL engine once and just thew in new belt with corrected timing and that engine still runs like a horse. The sound from the engine with skipped belt was enough to be heard from about 500 meters.