Timing Snap Very Bad

[Ibangedyourmom]

Hey this didn't happen to my car but a buddy of mine snapped his timing chain in his Acura, just wondering how fcuked up his car is going to be?

[redline]

Could be toasted engine to bent valves to nothing. Pull the head and find out.

[hjr]

basically, the worst that can happen is the entire cyl head might have to be replaced. Im not sure how the whole engine would be toast from a snapped chain.

[^SkylinE^]

There is interferance and free running motors. Hondas are interferance and by the name you can tell what happens. When you break your timing belt the valves run free and hit the pistions. I think you buddy is screwed this happend to my friends talon a few months back. I believe that interferance motor are higher performace than free running too. Good luck

[JustinL]

Probably just bent the valves. It could be a good time to do some upgrades while he's in there. It's not a huge job to replace the head, but a high performance head might be more expensive.

I'ts unlikely that the bottom end is too bad. When I threw my belt it just bent the valves up out of the way of the pistons and freewheeled.

But redline is right, pull the head and find out for sure.

Justin

[ls/vtec-crx]

Basically it's a timing belt not timing chain. Best thing to do before ripping off the head is to put a new timing belt see how it runs and do a leak down test. That would would be the best way to do it.

[rice_eater]

how is that better man? if that valves are indeed bent then he has to do the work twice...it's not that much more work to do to pull the head once the timing belt is off...all that's left are the manifolts which shouldnt take much time to take out. But to pick a somewhat in the middle aproach why not put the timing belt on and spin the crank and see if there is any touching of the valves with anything...then take out the rocker arms and compress the springs with a wrench and see if the valve rubs or hits anything...if it doesnt then your valves are fine, if it does pull the head...

[hjr]

ahh, taking a head off is an involved process. You dont just 'do it'. You NEED to have a manual for the romoving procedure as an aluminum head may warp if taken off incorrectly (which wouldnt really matter i suppose if its farked anyways, but its most likely not, so this is important). Now im not saying its hard, because it really isnt, but time must be taken to make sure its done right. As for a new timing belt and testing it, well thats not a bad idea. Time the cams and throw on the new belt, then do comp. tests on each cyl. to check for a leak.

[T5Bird]

Originally posted by ^SkylinE^
There is interferance and free running motors. Hondas are interferance and by the name you can tell what happens. When you break your timing belt the valves run free and hit the pistions. I think you buddy is screwed this happend to my friends talon a few months back. I believe that interferance motor are higher performace than free running too. Good luck

That's a big assumption that ALL Honda engines are interference. My '91 had the timing belt snap at 4500rpm, not piston to valve interference. New belt and a leakdown test and she was good for another 150,000k. But yes it is true that SOME Honda engines are interference motors.

[^SkylinE^]

Ya learn sumthing new every day!