Well all was well till I stopped to get some beer for the weekend and when I went to start her back up a mechnical sound reared up and it was a no go.

So a tow home was required.

Pulled the driver side cam cover off and everything was as it should be. I figured that it might be the starter motor..... Called her a day and decided to do the passenger side this morning.

Just finished getting the cover off and looking at me is a snapped secondary chain. It pulled apart in the middle of the link. WTF is this chain made out of old pop cans?

So the last week of my holidays is not as enjoyable as the first.

Question to the pros is Where to I go from here? I am assuming that because it snapped that the valves should be alright. I am most likely wrong.......of course. Is this a common problem?

Anyways not impressed with this POS chain..

Any info is greatly appreciated.

 

Unless all the exhaust valves were nearly closed when the chain snapped, a very unlikely scenario, there will have been contact with the pistons resulting in bent valves, possibly piston damage. I would pull the head to inspect.
RJ_________________
97 XK8 85K mi

 

Bummer indeed.

The chain snapping like that .... it's possible somebody had used one of the tensioner replacement kits that included a chain with a "monkey link", an open link you close yourself with a removeable pin. Not a good thing.

This is an interference engine. The valves and pistons occupy the same space, but normally not at the same time. You may have gotten lucky and not crashed a valve into a piston. Or you may have been unlucky.

Lots of threads here describing similar experiences. See the search tools.

Good luck.

 

Had the plastic shoe broken off the chain tensioner? This would damage the chain. It would be unusual for the chain to fail spontaneously without some other factor in play.

 

Sorry about that . . . but we told you so . . . .

Anyone that is still running plastic tensioners should take this post, and the many like it, to be a final warning.

I would speculate that the cause of the broken chain was that the plastic slipper on the tensioner came off and got caught between the chain and sprocket.

The repair issue is 'did I bend a valve'?

You can remove the exhaust cam and do a compression test or replace the chain and tensioner, align the cams and then do a compression test. There are lots of pictorials on the subject here for further information.

Best wishes on surviving the experience without a new head!

 

Had the tensioner's upgraded to the metal type? If so, Dennis' 'monkey link' scenario is a distinct possiblility and a sign the the other side of the engine will need a chain replacement also.

 

The tensioners are the 2nd gen and I am waiting for the metal ones to come in. The tensioners are complete and look fine. I do not believe any work was done with respect to the chains. Will get a pic later to show what it looks like. It looks like it was just pulled apart in the centre of the link.

 

If you remove the exhaust cam be very careful about the procedure. You will have to ease all the cap bolts a quarter to half turn at a time and make sure the cam is able to move to avoid breaking it.
RJ

 

Well i noticed a piece sitting in the area and pulled out the tensioner. Its the bottom shoe that has come off. To be honest I was not even aware of this running surface.The rest of the tensioner is there and the chain would have been riding on the metal surface underneath. Although there is no marks of anything ever rubbing on the surface. So I guess the chain snagged the edge of the metal plate and pulled apart.

May have got lucky as I do not think the motor had a chance to turn over. Will know after I pull the head off.

Not going to be fun but it will be a learning experience.

 

Ok I looked at a pic of the new tensioner that I am waiting for and yes, there it is , a bottom shoe. So an additional question is how long is the new tensioner good for?

It looks like the shoe could off just as easy and the second gen. Is the material thicker or just better? Asking this because I do not want this little part sitting in the back of my mind after I get my baby back on the road.

 

That 3rd gen tensioner has been in use since 2002 and I don't think there has been a report of failure to date, but who can predict the future?
RJ__________________
97 XK8 85K mi

 

The earlier Tensioners failed mainly due to shrinkage of the Plastic.

The Plastic on the Wear Surface was molded tightly over the Shoe with no provision for shrinkage due to heat and time. It will separate from the Shoe and get caught in the Chain or disintegrate with pieces falling into the crankcase.

Similarly, the Plastic Body can shrink and crack free of the metal tube and the entire Tensioner assembly would come apart.

The latest generation of tensioners have a all metal body and the Plastic Wear Shoe is Captive but "Loose" on the metal post so that shrinkage will not cause failure.