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HELP!! rattle then engine stopped wth?!?!

4K views 25 replies 10 participants last post by  Fallis 
#1 · (Edited)
#2 ·
sounds like your cam chain tensioner failed.. timing may have jumped. The fact your cam chain is lose is a tell-tale sign the cct failed. Timing jumped a little, wont' run. Jumped a lot, the valves are all bent as the pistons hit them.
 
#4 ·
yes that's what's happening. the piston is hitting the valves.

if the timing is off 1 tooth it will turn over. I never tried it 2 teeth off.

cct=cam chain tensioner.

you will need to put the timing back in right before you can test the compression of the engine to see if you did in fact bend some valves. that is if the motor will turn over by hand with it in time.
you can pull the tensioner out to inspect it. there is also a pretty expensive guide in there as well. you should replace them both if you have to do one.

anyway, here's a link to the factory service manual. everything you need to know is in it.
http://www.r6messagenet.com/forums/...254-r6-service-maintenance-repair-manual.html
 
#6 ·
First, the tensioner is now garbage and needs to be replaced. That is the least of your worries. I don't think there is anything you can do now but pull the head and inspect the damage.

It's not clear weather you have been turning the engine by hand or with the starter, but a sudden stop and freezing is very bad news. Yes, it can still turn when the timing is off a little bit, but when the chain is freely skipping over teeth it will be likely to end up with pistons colliding with valves. At this point you may even have valves that are permanently open because they got bent or some other significant damage like that. You won't know how bad it is until you look inside.
 
#11 ·
It's not just the valves that you need to worry about. Valve guides and seats need to be checked (I would have the seats cut and lap the new valves in). Checking and replacing valve guides will involve special tools. Also, since you mentioned the buckets came out of place, those and the bores that they sit in need to be checked for any gouges.


First you need to download the service manual, from this link, and see what your getting into (around pg. 150)

http://www.r6messagenet.com/forums/...254-r6-service-maintenance-repair-manual.html


Honestly, it would be cheaper and easier to get a decent head from a salvage yard or seller that will guarantee that it is good. Spray some carb cleaner in the intake and exhaust ports and verify that the valves don't leak. Check the sealing surface for flatness. You might have to take it to a machine shop to find someone with a calibrated straight edge to check it (they might charge you $5). If its all good bolt it on and forget about it.
 
#12 · (Edited)
Does the bottom end spin over nice now?No catches or noise?How about where the valves hit the piston?No marks?Did you pull the cams out and check them?Sometimes they get bent from pressure of the valve hitting the piston.Make sure you check around the guides as sometimes when a valve gets bent,it pushes the guide sideways and cracks the head.I,d probably get another engine or head,it will probably cost around $5-600 to buy the valves,guides,seats and such and have the machine work and assembly done plus the down time and that not counting the cams and might have to get timing chain,gears and adjuster from what you said about the chain jumping
 
#16 ·
try putting it back in proper timing and see what happens, you can't really hurt it any more than you already have, if the motor still spins freely and never locked up you may be O.K.

there is a possibility you "nicked" a valve slightly and it could burn later on down the road but if you only had it off a tooth or two its probably still fine
 
#18 · (Edited)
If you turned it by hand and it didn't hit then it didn't hit from cranking it with the starter.

I put mine a few teeth out and it still never hit anything. My chain was stretched and I couldnt tell if it was right or not. So I moved it around a few places. So if u have trouble lining up the timing marks
You need a new chain
 
#19 ·
Hopefully I'll be lucky. I was planning on getting in there some time over the winter break, the engine's just 40 miles short of ticking over 40,000. Just a bit bummed my season was cut short because of this.

Thanks for the tips, once I get everything re-timed I'll see about doing a compression test to see if I've got to go in any further. Hopefully when it jumped it only jumped a little and not a lot.
 
#21 ·
I think what happened was the tensioner appeared to be tight and applying pressure to the chain but wasn't. When I turned the engine over by hand the valve spring pressure sprung the cam ahead from whatever slack was in the timing chain and the tensioner rapidly tightened up again. I'll find out.
 
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