Wish i went to Uxbridge.

ian.stewart · Post by **ian.stewart** » Sat Jul 21, 2007 10:48 pm

The pully was loose, so was the bolt, only because the bottom sprocket was missing, so it had nothing to lock up against.

Post by **Coops** » Sun Jul 22, 2007 11:20 am

thats a right bugger ian,
hope the pistons and heads are not damaged.

kiwicar · Post by **kiwicar** » Sun Jul 22, 2007 1:35 pm

Hi Ian
any idea why the bottom timing chain sprocket broke?

never heard of that one before, must have taken alot of energy to break a sprocket axially into three bits, sure it is not the result of somthing else going wrong?

best of luck
Mike

ian.stewart · Post by **ian.stewart** » Sun Jul 22, 2007 2:34 pm

I have no idea why it broke, I think it broke after lifting off from a burn out, so there would be some reversion on the chain on over-run, so I was wondering if the chain climbed a tooth and jammed.
Ive got my engineering hat on at the mo, but untill I can get the engine apart fully any meaningful answer is just guess work, making an educated guess about the chain, this could have easily taken off a tooth, and if it has jammed near the root of the keyway, that is quite a good point to act as a stress riser and break thru the keyway, which is where it has.
I will try and download some pics later, The key is deffo not rounded off, but it has some damage due to hitting bits of shrapnel

ian.stewart · Post by **ian.stewart** » Sun Jul 22, 2007 4:18 pm

Ive taken one head off now, and it appears to have clipped all the exhaust valves, mainly due to the reason being the valves are too big for the cutouts

I will do a parafin test tomorrow ust to see what, if any are bent, but i think I will change all the exhausts, just for safety,
The 4 pistons I can see dont appear to be too damaged, with just a small witness mark on the edge of the cut outs

mgbv8 · Post by **mgbv8** » Sun Jul 22, 2007 7:15 pm

Sounds like it may not be too bad at the moment then mate?