Disaster-->My cam-chain broke

Could you post a picture of the exhaust side slipper shoe and the crank shaft teeth?






A loose hyvo chain will often make a knocking noise. It won't generally make a rattle sound because of the rubber shoes that it runs against. The knocking sound is evident at idle especially.

Was your motor making that sound before the chain broke?

It's difficult to say exactly what happened here. The ends of the broken links do not have a sharp, clean break look. In the first picture it looks like the two inner most links let go first and the outside link held for a while before it broke. Then you have the other link in the second picture coming apart as well ...

floivanus wrote: Basically need a crank or pay someone to take there's apart, ship it to you and get a shop to take your crank apart and press the new center in align it and check everything.

Poor elr

+1
First the frame; then the bodywork; now the engine. Sad.

LarryC wrote: Could you post a picture of the exhaust side slipper shoe and the crank shaft teeth?

I will take photos later on today and post them.

A loose hyvo chain will often make a knocking noise. It won't generally make a rattle sound because of the rubber shoes that it runs against. The knocking sound is evident at idle especially.

Was your motor making that sound before the chain broke?

My engine was making that sound before the chain broke, escpecially at idle speed, so I think you are spot on with your description. The sound didn't happen very often though, I think I might have heard it only 5 times or so in total.

I guess the chain has either broken from hitting the teeth on the cam sprocket or cam shaft sprocket, or it can also have happened from snagging on the knob on the front inside of the head as shown in previous photo.

That damage to inside of head could have been from after chain broke, the damage appears to have started on the gear side of chain.
Check that pm I sent you when you first posted about the chain, then check the gears.

To to hi-jack the thread, I decided to replace my timing chain while I had the jugs and head of. Bought a BK from Z1 with matching master link. Anything I need to be aware of here? I don't want to end up in the same situation. I'm using the stock adjuster

Yours uses the old style chain,did they sell you an install tool with it for master link?

LarryC here are the photos of the guides along with the sprockets.
It was a bitch to get a good picture of the crankshaft sprocket with the cell phone, especially when it is still inside the crank case

Intake camshaft sprocket

Front guide has a nice long scratch in it, but no wear:

Top guide also has the same scratch in it:

The carb guide has no scratches and shows no sign of wear.

I wonder if the scratch on top and front guide were from the chain being thrown forward with the piece of link pointing outward after the chain broke.

WOW,

I look at that stout HYVO chain and then think about my smallish peanut link cam chain ......... kinda lost my appetite..

4TheKZ1000 wrote: WOW,

I look at that stout HIVO chain and then think about my smallish peanut link cam chain ......... kinda lost my appetite..

I hear you.... I have never seen a hyvo chain break. The troubling part is more than one spot coming apart. There is so much inferior crap getting into the market from China that it truly worries me. Check this out. I have seen a peanut chain from a big block 1327 motor that when through absolute hell and did not break.

The front idler sprocket was not turning half of the time. When they assembled the motor the bolt they used to hold the little slider shoe in the block was too tall. That in combination with the truly shitty machining they do for the idler sprockets in after market big blocks allowed the idler pin to move. In turn it would bind on the too tall bolt. The chain was skipping across the sprocket teeth!!

When the engine was torn down there were sections of the cam chain where 7 or 8 links were so bound up they would stand straight out like a pencil!....YET the chain took the punishment without breaking.

Please... When you get the crank out post more picks of the sprocket and any other related damage you find. See if the main cap shows any sign that the chain was rubbing on it for a while. If so, then excessive looseness could be the source of the problem. I won't give an opinion on what caused the break until I have more clues to go by.

PLUMMEN wrote: Yours uses the old style chain,did they sell you an install tool with it for master link?

No. So I guess that is my answer. I will buy a masterlink installation tool. TY