i changed my timing chain tensioners yesterday!!!!!

[Brakebuster]

yup,

after sourcing all the right tools for locking off the cams , and the crank pulley remover along with the flywheel ( torque converter ) locking tool , and after buying all the right parts from my local Jag dealership including all new gaskets for the cam-cover ( outer seal, spark plug seals , bolt seals , variable cam sensor sealing ring etc etc ) i plucked up the courage to take the engine apart


my catalyst for this job was two-fold,

firstly , i had minor oil leaks from a few places on the cam cover and the variable sensor seals, i didnt like this at all

secondly , the tensioners them selves, as they were an unknown quantity and i had just reached 90k miles in my 1999 Nikasil engined XJ8 Sov ( successful blow-by test recently carried out 19ltrs/ per something or other ?? )

with spanners in hand i removed all the cover trims and the spark-plug coil covers on both cams, and carefully replaced all the bolts back in their holes as not to loose any ( i did this all the way through he job), removed the coils and wiring and tucked out of the way , and proceed to remove the cam-covers , was a little surprised at having to guide the cover up and over the cam sensor on the front of the engine, the seal broke away as i did it, all the rubber/plastic seals were flat and pretty much U/S , thats why i had a full new set ( £78 ), did this on both sides


once all the top is removed you can easily see the secondary timing chain tensioners, they are the orange parts in the pictures, they start off as white, but with the oil and the heat they go orange and deteriorate and eventually split or loose a slipper against the chain


i then proceeded to set up the cams, this is done by turning over the bottom crank pulley by hand with a 24mm socket an a large ratchet , i did this until i reached TDC and the two pairs of cams ' flats ' were parallel to each other, this was checked with a steel straight edge ruler , once in this position i installed the locking tools and bolted them down very tight , while remembering it was into aluminium!!!
the picture below shows the cam locking tool, with the sprocket spanner and a 10mm Allen key for removal of the sprocket nut and washer

BOTH cams MUST be locked off together, as any movement is fatal to the timing ,

undo the two 8mm bolts holding down the old tensioner,

the exhaust sprocket can now be removed , the bolt is very long , and be sure not to drop anything down the covers !!!

while holding the sprocket and chain in one hand, remove and lift out of the way and remove the old tensioner, then drop in the new tensioner and replace the sprocket onto the cam shaft , screw in the cam bolt hand tight at this point, straighten up and fix down the new tensioner , then remove the spring retaining pin to tension the chain , then tighten the sprocket bolt to 70 lb feet with a torque wrench

do the same on the other side, ensure everything is tight and then check again , and then when feeling brave remove the cam locking tools , nothing should move at this point
this picture shows the new tensioner fully in place and tightened up after removal of cam tools



now for the results ...........

the original tensioners looked fine in place, but when they came out i could see that all the work was worth the effort ,
the right bank one had a 1mm split starting on it, but worse then this the bottom ( spring ) slipper was severely worn and gouged out, showing ' bubbles ' in the original plastic moulding wearing through
http://www.talkphotography.co.uk/galler ... Small_.JPG
the left bank one showed hardly any wear to the slipper, but the shank had a 4mm split in it ,
so all in all a top job methinks, the new aluminium tensioner can be seen in the background ,
BTW, the new tensioners require four new SHORTER bolts to fix them down, and £0.96 each....


it took me four hours on Saturday to strip the engine , and four hours on sunday to complete the job

all the mating surfaces were cleaned of oil and old gasket, and the engine was put back together,

i then ( with heart in mouth) turned her over to see if it was asucess ?
voila!!( sp ) she lives, muhahahaha

drover down to bristol and back today , very gingerly with the radio off, lol

but not a beat was missed

new oil next week and a new water pump and thermostat to fit

BB ( anyone want to buy the set of cam tools from me ??? )

[chris12]

Well done!

I am about to do the same.

Do you still have the tools? I could be interested in buying them.

Please phone me on 0121 355 1008 ASAP

Chris

[chris12]

I have just completed the job on my car which I only bought a month ago. I changed the upper tensioners only + the main gaskets, plug & VVC seals. As the car has done only 27,000 miles there was no wear anywhere, but given what is known about these tensioners I am very glad to have taken the precaution of eliminating the risk.

I made a bar to lock the camshafts in place out of a lengh of 1/4" building roof tie bar. I used a large parallel punch thru' one of the holes in the sprocket and a lever against the boss to hold the sprocket. The bolt that holds the sprocket on is very tight. I got a friend to help me torque them up

I approached the job with a fair amount of trepidation, but it's OK if you go slowly and carefully and are not in a hurry.

Water pump is next job.

Chris

[joejag308]

Its great to see we do have enthusiasts who can still "get the spanners out".........i served my time as a "motor mechanic" 40 odd years ago, then i went on to a career outside of the garage.
Things have certainly developed technically from those days, plus the will to get into the garage and work on the car.....apart form cleaning it of course. But gentlemen. those of you who do this kind of work, try not to make it sound so simple. For any member who has not done this work at all it could lead them up a dark and dangerous road if they tried to do certain jobs that could wreck their pride and joy.
For a pure novice to try and replace the top tensioners for instance it is a daunting and dangerous task ...............whereas to some its quite easy.
Joe

[robv12]

I too am about to change the top tensioners on not one but two V8's both pre Nikasil and both 110K plus miles, and no evidence of a change previously. I guess I'm lucky, I have done about six of these before, and luckily under the guidance of David Marks in a fully equipped workshop. I'm now doing these at home with basic tools and the specialist tools hired from JEC tools. Six months ago I would not have attempted this job, BUT, when you actually get in there it is relativley simple, the time is taken up on preperation and removal of parts to get to the tensioners, once there it is really quite idiot proof, things will only go back together one way, my advice is have a go, be careful, methodical, clean and tidy and if in doubt take pictures on strip down and ask if you hit trouble on the way

[joejag308]

Speedy........im with you 100% in what you say,and all the precautions in the world are needed if its your first time. Lets just leave it there for a bit and have a look at the things that can go wrong.........mainly preparation with the timing gear, getting the essential parts for locking all that in.
Once you have it all in place its then done in stages where you should log every nut and bolt you take out etc ect, then after uninstallation there is the installation of the new tensioners and then cleaning every part as you build it up again, what do you think of one alternative someone gave?
That was to renew the holding bolts as the old ones will have stretched,that has got to be addressed as a necessary item (if you are doing it correctly that is) when all this stuff has been attended to and clean oil and filters fitted.....who is going to start the engine?.....i would have all my finger crossed at this point ........if it starts and all is well its the best feeling in the world, if it doesnt, and funny clanking noises emerge from within the engine, oh boy what a feeling that must be.
I at my age have a perfect and painless way to do the tensioner job.
Pick up the phone and call the nearest Jaguar Specialist and get a quote
for the job doing. Your only worry would be .....has he kept the engine clean????........... Joe

[robv12]

Joe, re your comment on the tensioner bolts, it is VITAL that these are also changed, not only can the old ones stretch, but the new ones are slightly different to fit the new style tensioner, and at 80 pence each it;s peanuts, so just do it!!, BTW my total parts bill inc vodka and tonic (VAT!!) and post was 119.38 from Berks Jags, next day delivery, way cheaper than main dealer who wanted 54.98 plus vat each tensioner, then add all the gaskets etc, and of course none in stock, no surprise there then!! BTW, your email is full, and keeps bouncing back, Rob J

[joejag308]

Rob yer right its just alerted me to empty it..........not that much in as it happens i will try and get some more space if i can find out how to do it

[robv12]

well we changed two sets of top tensioners yesterday, took two of us five hours to do both cars

brake busters pictures above were hugely useful

the first car a 4.0L S reg 130K miler, showed signs of someone being in there before us, had orange tensioners fitted, one was ok, the other on the right bank was metal to metal, however we has some head scratching as one inlet cam was out of position slighty and the cam locking tool would not seat correctly, early morning phone calls to David Marks and Neville Anderson at NE Jag 0191 586 7770, solved the problem. We locked the engine at TDC with the speed sensor plug and gently bolted down the locking tool, as promised by the experts everything then came into place.
Car fired up, and as normal a little noise until the oil primed the new tensioners

the second car a 4.0L R reg with 107K, went even easier, straight forward one and a half hours start to finish including a cuppa half way through. The tensioners on this one were black, both completely split, both plastic slippers had long gone and the metal slipper was well grooved
Again a little noise on first start up then as quiet as a church mouse
However with this one we will be going in again to change the chains, just in case they have stretched or become damaged running like this for so long. We also intend to drop the sump and have a look for the missing pieces, they have to be somewhere!

So I guess the moral here is, buy a pair of chains when you get all the other parts, it will save you at least two hours going back in to do them

total cost of this job, parts 120.00 for tensioners, new bolts, gaskets from Berks Jaguar, 10.00 for oil well gaskets from Jaguar, plus tool hire from Annie Jenkins JEC, so round about 200.00 all in

A job well within the home DIYer's capabilities, if you have basic knowledge and the correct tools, the only tools which we used that were not 'bog standard' were the cam locking tools, a couple of deep sockets, and a 10mm hex drive to release the exhaust cam sprocket, which on one car was tight, very tight way over the 70ft/lb recommmended, man mountain must have been there before us!

[Brakebuster]

top job there speedy ,
( speedy by name , speedy by nature ) lol

thanks for the mention on the pics ....


as for the missing parts, they will be in the bottom of the front timing case cover, and the oil filter should have taken care of the smaller bits suspended in the oil,

so once they are both fully done i would recommend a full oil change, filter and new sump plug to ( they have been revised ) , cheap genuine Jaguar oil can be found online, as posted in one of my other threads ....

once again, top job,

it just goes to show, even though they are advanced and complicated, they are still able to be looked after to a high level by the DIY home mechanic.......

i wonder how long a Jag Tech would take to do the same work ?????


BB

( TB removal and cleanup for me next, just cuz i can, lol )

[robv12]

thanks for the kind words brake buster, we intend to drop the sump of one car clean out the oil pick up pipe, new oil and filter and sump plug, this will all be done in the very near future

started both cars from cold this morning, one is a little noisy still, but the worst one of the two is as quiet as a quiet thing now, just as it should be

tried to show some photos here, but failed miserably!!!, to techy for me!! wanted to show just how bad one set of tensioners were

[Aerosteve]

Replaced my secondary chain tensioners today. Hired the tools from the Club and followed Brake Busters excellent advice. Some comments:

1. The old tensioners both had cracks about 7 mm long in them;

2. Should have read the advice more closely, as BB commented that shorter tensioner bolts are required. The old tensioners are about 5mm deeper than the new ones so new original bolts, which were included with my new tensioners, are too long and 'bottom out' in the threaded holes. I shortened mine and ran an extra 5mm of thread down them.

3. Two of the threaded bushes in the cam cover, for the coils cover, came out with the screws. Just epoxied them back in.

4. About 7 hours work on my own, taking it nice and steady. The JTIS workshop manual on CD from 'greatworkshopmanuals.com' is invaluable. Fairly straight forward job for a competent amateur machanic.

[joejag308]

Steve good to see a guy having the guts to do his own work on a rather technical job for home work...........it does seem like you have managed to do it ok it must give you satisfaction.........i do hope any help from the forum you acquired is appreciated thats what the forum is all about.
Joe

[u102768]

I had mine changed recently (98 XJR) and I was a little disappointed (but I guess relieved) to find that they were in A1 condition.

No cracks, the shoes were only lightly scored and they still held hydraulic compression with a little oil inside. They looked like they would have lasted another 70,000 miles.

The person who did the job in the end is an ex-dealer mechanic who has just started his own business and he said that the dealer actually use the method I described on another thread where you remove the exhaust cam instead of using the lock down tools.

[prospero]

Brake Buster ,
You have pm.

prospero.