Hi, looks like I've got a broken timing chain tensioner/guide. Does the engine need to be pulled or just the radiator?
Also, what could happen if the broken guide isn't replaced?

Thanks,
Frank

 

Don't have experience with this specific engine, but in general terms broken guide and tensioner are bad news as it leads to timing chain jumping, destroying the engine in process.

My recommendation is to replace all accessible guides, replace chain, and replace tensioner and under no circumstances drive/start car as-is.

 

Welcome to the forum Frank,

Sorry to hear about the engine issue.

I've moved your question from Canada Region to XJS forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Search Jag-lovers.org... search forums section for your problem and how to fix it...big trouble for the engine if you operate it......most likely best solution is to remove the engine...make plenty of photos as you go along and read heavily on the Jag-lovers ...."search forums" for timing chain tensioner/guide ..Best, JW

 

have sent you several replies as PMs and not able to determine if you are receiving them or reading them, JW

 

How do you know its a broken tensioner, what are the symptoms.

This forum has some of the most knowledgeable guys on the planet regarding the V12

 

I have done that in situ, with the heads and sandwich plate left in place.

NOT a nice task. VERY awkward working angle of the dangle.

A VERY long time ago.

You will need to remove the radiator, a/c condensor, bonnet, and lots of little things in the way.

Cam covers off, so inlet manifolds OFF and fuel rail etc.

It took me 4 days, and I vowed that the next one would be engine OUT, and at least the sandwich plate OFF. Has not happened yet.

DO NOT drive it if that tensioner is broken. The chain will whip and eventually come out the side of the timing cover, but that is EXTREME.

The symptoms are usually a slight "hunting" at free rev 1500rpm. Slapping can be heard on rev down sometimes.

You really need to establish that it is in fact snapped. RH side of the chain will be slack when felt via the RH camcover opening if it is broken.

If you want me to write a Word Doco from memory I will do so, and that is a request I will wait for, as it will be a long Doco.

You will require a sense of humour, FACT, and some very savage language, FACT, and a sense of adventure will help heaps. Then the brain reasoning to keep on track as you ponder "what the hell am I doing", as you reach for that NEW bottle of JD.

 

Yes Docccco, will provide the JB next time I'm in "stralia" . I thought only the savages used savage language. Best, JW

 

I've done the tensioner in my 91 5.3 a few years ago. Follow all the advice above on starting/running. Yes its a lot of work and very time consuming, but "pretty straight forward " if you work on this car yourself! Everything must be taken off or pulled out of the way: hood, rad, water pump, power steering pump, FI, cam cover, etc. Taking the timing chain cover (TMC) off and reinstalling it isn't real hard but you must read up on this in The Forums and Kirby's The Book, lot off advice making the job "easier". This is also good timing to clean, repair, replace, all the stuff needed in the front of the engine.
Lawrence

 

Thanks everyone for your input. Winter will be approaching soon so I might give it a try myself since I'll have lots of time on my hands.