Before I get blasted I have searched the forums for the answer and I'm guessing the keywords I'm using aren't the correct verbiage.

I've got a chance to purchase a very nice 1995 XJS 4.0 i6 that has a timing chain slipped. Is the 4.0 an interference motor. I.e Do the valves smack the pistons when the timing slips?

 

Good question, and welcome to the forum! First time I've heard of a timing chain slipping on these cars (doesn't mean much though). I don't know if it's an interference design or not. One of the experts will be along soon enough to enlighten us.

Got pics of the car?

 

FWIW - I know the older 4.2 has an interference head so I'd assume that the 4.0 does also. But you know about assuming ;-))

 

I would love to see how a Jaguar 4.0 slipped a chain. Very, very, very hard if not virtually impossible to have happen.

 

Over-revved with a broken or underperforming chain tensioner is about the only way I can imagine it'd slip a tooth. Or it was put back together badly...

 

Slipped timing chain seems to be the latest catchall for unknown engine problems. I suppose it can't ever be totally discounted but l wouldn't take the bet at the prevailing odds.

 

Having had mine apart on my x300 I can't even see that happening. It'd be pretty hard to do and would have to be a really neglected and abused example.

 

The AJ6 is an interference engine so I think every chance that the AJ16 is as well.

Still intrigued by the slipping chain....

Good luck

Paul

 

What is more likely is failure of the chain guide material causing noisy chains.

Jaguar had a problem with these back when I was in the dealership. Can't remember which years exactly.

Also as we know there is a modified chain tensioner. Maybe the OP is being fed duff info.