hi, i'm looking to buy/rent the cam locking tool and anything else i'll need to change the tensioners on my 97 coupe. it sounds like a bag of gravel when it starts :O(

 

For the parts and tools http://www.motorcarsltd.com/

 

thanks, i called them but a $350 deposit and a $120 fee to rent it seemed ridiculous. also the parts were cheaper at the dealer so i made something. pretty easy really its just a chunk of metal with a couple of holes drilled in it..

 

Interesting... got any pics ?

BTW the only thing that puts me off doing the chain renewal job myself is that the AC system needs drained, according to the 'Jaguar World Monthly' article I have in front of me.

How do home mechanics get around that ?

 

I am sure that the article was referring to the primary tensioners when most only replace the secondary. The secondary absolutely do NOT require removal of the A/C condenser.

Excellent pictoral of the process here: http://www.mediafire.com/?mijhydngtog

Tools can be rented here: http://tiny.cc/Tools

 

I have done dozens of timing chains and removed the front cover for primaries and guides etc. and I have never had to remove the A/C condenser or even the radiator. I do remove the fan assy but never the water pump unless it needs to be repaced. I gave up using the crank damper holder when I was at the dealer because someone lost some pieces and it was time consuming to install. I use a section of poly drive belt wrapped/taped around the damper and a 24" chain wrench from Harbor Freight and a 24mm socket on a 24" breaker bar. I have never had a damper fail or slip even with a very tight damper bolt. Don't install the crank or cam locking tools until the damper bolt is broken loose and never use it to hold the crank to loosen the damper bolt. You will bend the timing segment in the torque converter drive plate and then have a cam/crank syncro fault with poor running and misfiring. (I know this because the guy 2 stalls down from me did this and it took him 2 days to figure it out and replace the bent drive plate)

bob gauff

 

The tool sets are in Hawaii for a couple of weeks being used by two (2) members. If you still need hem, email me by going to my profile page. If you only do the secondaries, the cam lockdowns are pretty simple. If you have any machinist skills, they are easy to fabricate. I cant see how anybody could charge a couple of hundred to sell them. There is of course, the 'Jaguar Tax".

 

thanks for the offer. i'll bear it in mind if i run in to trouble. i'm just using a section of 2 inch square tube with two holes drilled in it to hold the cams. seems solid enough to me. i get the secondary tensioners and bolts tomorrow from the ford dealer. i'll try the slip in by removing the exhaust cam sprocket technique. any warnings or tips when doing it this way?

 

It is a pretty straightforward job. Once the cams are locked in place, pull the gear (which is a slip fit, and not key'ed or otherwise fixed into position).

When I did mine, I was overly concerned on the proper tension of the chain as the locking bolt was tightened down. As it turns out, you only need to take up the slack in the chain, not tension it to any pre-specified torque settings or the like. Just be sure to tension the cam sprockets and chains in the correct orientations.

After installing the tensioners, and when you are finishing up, some chain slack appeared after removing the cam lockdown bar. It was more noticeable on the A bank (Passengers Side). If you look closely, you can see that after removing the bar, the cam flats have rotated and are no longer inline with each other, nor flat. This is OK. As long as the driven side of the chain, the side opposite of the Tensioner, was tight when the sprockets were locked down, everything is set properly.

Some other thoughts:

Cam cover brass inserts.
Take extreme care in removing the cam cover bolts. This is delicate work. The little brass inserts for the coil covers can twist out of the cam covers. Be sure to use very little torque in tightening. I would suggest using no more twist than you can get from a screwdriver. If you do twist them out, there is a fix using JB Weld.

Oil Leaks around Cam Cover Bolts
Each bolt holding down the cam cover to the cylinder head has a small rubber O ring-type grommet. They seal the bolt from oil leaks. If you have an oil leak, do not tighten the bolt… get a new grommet. If you try to stop oil leaks by tightening down too much you will break off a bolt in the head. Then you are in for some serious problems. The bolts and grommet assembly pull out of their seat in the covers. The grommets are easily swapped out. They are available from any Jag Dealer and many aftermarket sources.

Cam Cover Bolts
I used quarter inch drive sockets, extension bars, and a swivel to remove the difficult cam cover hold down bolts on the lower rear of both covers. Same for the coil covers. There are two (2) cam cover hold down bolts UNDER the coil covers. .

 

I'm asking this stupid question, well because its a stupid question but here goes. Why can't you just remove the tensioner bolts and remove the tensioner? Cant' you just lock a set of vise grips on the body and just pull the sucker off? Just asking because its not like your going to reuse the part anyway.

I remember when they went to repair the hubble the last time. they had a stuck part that their million dollar tool would not work on. So the astronaut ask if he could just pull it out or break it off then do the repair. The engineeres thought about it for a while and finally said go ahead. No tool needed just jerk the thing out of the way, install the new part and pull the pin.

 

A PM from Gus prompts me to clarify the how the Tensioner Tool Set Rental Program works; and how it got started.

I do not own the tools. The set was purchased by the generosity of one RichyP, who is a founding member of our sister site, MaxPerformanceCars.com. RichyP bought the tools using his own money, and donated them to the MPC Forum in order to provide a service to its members. I have coordinated the rentals, and acted as custodian of the tools, since the rental program was established a couple of years ago.

Consequently, whenever anyone asks to rent the tool set, I instruct them to first register as a new member on the MPC site; and then follow the MPC rental application process. In deference to RichyP and the MPC membership it is only fitting that tool renters should also support the MPC site by becoming active contributing members, not just tool renting pseudo members.

The MPC site is located at http://www.maxperformancecars.com/ They are a great bunch of true Jaguar enthusiasts. Unlike some online sites that are more involved with cosmetic aspects of the XK8, they are also interested in the engineering aspects of our car including: The development of a 600 HP aftermarket supercharger and a freeflow stainless steel exhaust system. Stop by their site and say "Hello!".

 

I might be easier to pull the tensioner out as you suggest; however, you would still have to lock down the cams because they would move after the tensioner was pulled. Then you now have the problem of taking up the slack [previously held in check by the tensioner]; and insure the cam timing was syched to the crank timing. This would basically require that you follow the steps in the established procedures. eg. Lock the crank in place, and pretension the chain. So I dont see how one can avoid doing it as noted.

 

Thanks for the great advise, at which point should i remove the pin in the new tensioner? before or after i retighten/tension the cam sprocket?...thx

 

IMO it would be a mistake to just start unscrewing things w/o a plan. You should really find one of the Tech Writeups or FAQs and/or get a JTIS printout before starting this job.

While not complicated, there are many small steps. Do a search and you'll find a couple of good write ups. Here is my set of bookmarks on the subject:


http://www.jaguarforum.co.uk/viewtopic.php?t=11333

http://www.jagservice.net/jaguar_v8_...tensioners.htm

http://www.jag-lovers.org/snaps/snap...1143069950&n4=

http://www.roadfly.com/jaguar/galler...36878,1;-54,3;

http://www.jagservice.net/jaguar_v8_...tensioners.htm

 

The secondary tensioners can be changed without special tools by lifting up the camshaft. The procedure is described here or on a similar board.

 

i got started today and ran into some problems. first the oil pressure hole on the new metal bodied ford tensioner is not in the same place as the jag one i removed. the ford one is dead in the middle whereas the jag one is offset to one side. is this a big problem?

second the old tensioner was not as bad as thought. i had a large amount of chain slack and i thought a big piece of the heel slipper had come off. well with the new tensioner in its still the same. on the right bank top side, the heel solid side the chain is super loose like a whole link and there is no where to tighten it as that side is solid and the slipper is below the height of the cams so i'm very confused how it could ever be tight. is it known or possible for the chain to stretch this much?....thx

 

There is a RH and LH tensioner.
The oil holes should line up.

 

They don't. I just swapped them in mine and noticed the same problem. Though it does appear that there is enough overlap of the holes to continue oil flow. mine are also the jag part and not the ford part. not that it makes any difference as the are the same part.

 

No, no you don't. there is absolutely no reason to remove the A/c condenser. none.

 

The best tip I got was to place a section of cardboard over the backside of the radiator. This prevents damage to the fins. I was amazed how many times a tool or part smacked into the cardboard and each time I was thankful for the protection.