I apologise for asking but I have searched and cannot find the information I need.

Having got the car through its MOT which was never a given it's a keeper so I needed to check the secondary cam chain tensioners and bother they are nice looking second generation but now I now that I should really upgrade them to the metal ones. A previous owner will have changed them and its only done 76,000 miles now however they are ticking time bomb.

I'm going the zip tie route and I am sure that some said to rotate the engine until all exhaust valves are fully closed and hence to pressure on the camshaft when you retighten it.

On my old Range Rover I just put a big spanner on the crankshaft nut or something at the front of the engine and heaved.

Does this work for the Jaguar V8 as well? There's a fine big looking nut there and the engine rotates clockwise when looking at it from the front - right?

Or can I just be very careful to tighten the cam cap bolts very, very slowly and evenly?

I do apologise for asking this question yet again but I can't find the answer!

Mike

Replying to my own post - I think I have my answers now.

Yes you can turn the 24mm nut at front of engine clockwise
Try to get all cams off tension
Work very carefully when releasing and tightening cam caps - a lot of finger feeling
When tightening use pre marked bolt head positions marked before release

I'm not sure the very low torque values are much help as the threads will inevitably have oil on them.

So I think I'm good once I get the parts. Mail order or dive to SNG in Bridgnorth? It's only 40 minutes away.

Mike

Ya' beat me to it
Sounds like you have it all correct.

Yes, always rotate the crank in its normal direction - clockwise looking from the front as you say, and take your time with the cam bearing cap bolts

I'd lift the RHS cam cover first to check (it's the easier one as you don't have to fight the dipstick...), although you never know if some cheapskate has only done one side

If you do find you already have metal tensioners, it will do no harm to drop the sump and check there's no detritus left in there from the old plastic tensioners that wasn't cleaned out. This sometimes finds its way into the oil pickup strainer.

Apologies for hijacking the thread, but on the same topic.
​​​​Any benefit for getting the Jaguar tensioner vs aftermarket? About £80 extra per each original one at SNG Barratt.

Your call, although I always go OEM with critical parts such as these.

SNG is quoting the same price as Jaguar Heritage, but they should give you 10% discount if you mention your forum membership when ordering.

Don't forget the new, shorter bolts required for the metal-bodied tensioners :- part # is JFB10607B025

To add to the decision there's a guy on UK eBay selling what look like original Jaguar tensioners at £50 each. Branding looks right but the photos aren't great.

I think I'm going for SNG third party as they won't sell tat and who knows if the eBay guy just gets the bags and fills them with tat. I don't think he does judging by what he sells and the feedback but dealing with SNG does make you feel a bit better.

I have now done the job and I think if I ever had to do it again I'd get the genuine Jaguar parts. It's not a pleasant job - not so much the fitting of the tensioner although that's a tense process if you've never even touched a camshaft before - but the cam covers are very fiddly to get off and on again. So, for the additional money I think I'd go genuine for the confidence that the correct level of QA has been applied. That said the parts from SNG looked and fitted just fine.

the cheap tensioners are very good. make sure it has a red pin. some of the kits on ebay have the special bolts otherwise just put a washer on it