Hi all..I was going over my 1993 XJS and noticed a big leak from the bottom of the timing chain cover. With new orange and gasket I popped the cover off. My problem now is I can’t seem to be able to push the tensioner and cover back in flush against the mating surface…it seems to stand proud about 1/4”. I looked at my shop manual which was no use.

Is there a certain method to get the tensioner system back in so I can tighten the cover up etc ?

Many thanks for any advice

JB

 

You're talking about the front cover for the engine? The one that holds the front main seal and fits under the head? If so I thought it didn't have a gasket, in fact I have this tube of white gasket material from Jaguar that seals that cover. When I did mine I ended up removing the head because I couldn't get back underneath the gasket under the head, it hung up and ruined the gasket.

 

Thanks for the reply…I’m sorry but my first message is a bit confusing. The cover I’m talking about is for the upper timing chain tensioner which when looking at the front of the engine is on the left just behind the distributor.

I popped it off so I could fix an oil leak from it but I tried to put it back on and push the tensioner in, it wouldn’t go all the way in.

I think I’m not doing the correct method to put it in. Does anyone know if I can just pull the whole tensioner out without any bits coming apart inside and falling into the engine ?

Thanks again…JB

 

Number 15?

 

Hi Time Pilot….thanks for this. It’s actually the part with numbers28-30 on attached drawing

 

First of all the tensioner is on the RIGHT side of the engine.

Did you use an allen hex tool to 'ratchet' the spring loaded part back into the housing?

Jaguar issued a TSB on the updated tensioner.

 

Thanks motorcarman...phew...quick update as I worked on it this am and being very careful I managed to extract it without anything falling in.

no I did not hex it back but having this TSB helps me a lot as I might as well put the new one in

tks as always for help...JB

 

Quick question on the TSB…why do you need to depressurize the fuel system when removing and installing the tensioner ? I just can’t figure out why this is needed ?

thanks…JB

 

Did you read the Bulletin? (hint: Jaguar did not want the engine to start, just CRANK)

8. Use the starter to turn the engine - the movement of the chain against the
tensioner blade and piston will release the mechanical tensioner.

 

Thanks...yes read the bulletin but in the beginning before you remove the old one they say depressurization fuel system...I just popped my old one out with starting the engine first...hmmh?

 

To get the replacement tensioner to extend the spring release, the chain just 'slaps' the tensioner during CRANKING.

The engine is NOT supposed to START. (just turn over and actuate the tensioner release)

There will STILL be residual pressure in the fuel system to enable the engine to START momentarily. (that is to be avoided)

What part of NO START, JUST CRANK do you not understand?

 

Thanks motorcarman !

I have the new tensioner and followed the TSB line by line. I’m now just a bit stuck on how the tensioner forks should be orientated when you put the new tensioner in and the picture on the TSB not that clear.

Are the forks positioned horizontally or vertically when you install ? I read one person say horizontally but want to make sure

thanks as always for help

JB