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What would be the damage caused if a DOHC 4-valve engine jumps time??
I am aware that you can have bent valves, but is it possible for something inside the engine to punch a hole in the oil pan from it jumping time??
Thanks
 

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Very rare thing these 4V to jump a tooth in the timing. You really need to look at the root cause. It would have to be a tensioner passing oil or failed if it was normal to agressive driving. But first hand I have seen 1 time a fellow installed a set of off the shelf (Cheap choice in my Opinion BTW) Comp cams into a 4V never checked them by degree the cams. It was a low mile engine so they re-used the chains etc. They didn't want to pull the engine was the story. But on WOT it happened. This is what it looked like to us with the wear in the chain plus the stretch in the chains from some use plus the big load of WOT and most likely a bit advanced the valves made contact with pistons. Guess what something has to give. At first it looked like a skip but it actually cracked the gear on 1 of the cams that made the inital contact and when we pulled it apart it split into a couple of pieces. They tried to save some time and money and in the end start over. People don't realize that as things change in the timing the gap for the valve to piston gets very minimal. Not so bad in a low compression blower motor but this was a high compression NA set up. The reason that you can also purchase different thickness in head gaskets is to help make up space say from an engine rebuild where the heads and block get decked to restore the flat plane this will increase compression and basically add length to the chains. These 4V are precision engines. Guys that race these 4V's are wise to freshen them up pull the chains and check how much stretch, check those O rings on the tensioners etc. The little details will cost you $$$ if you ignore them.
 

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Also the dowel pin coulda failed... why there is a kit to install the bigger ones.
 

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What would be the damage caused if a DOHC 4-valve engine jumps time??
I am aware that you can have bent valves, but is it possible for something inside the engine to punch a hole in the oil pan from it jumping time??
Thanks
Did you get it fixed? What was the problem? My car just jumped timing.
 
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