Hello guys.

Quick background: bought my 1997 Coupe in early June, from a local dealer (it was a trade-in). Spoke to the doctor who owned the car for 9 years, and he told me the tensioners had been changed to 2nd generation plastic type many years ago. So I knew that I needed to update to 3rd generation metal tensioners, but it wasn't a code-red emergency. No rattles on startup, and I wanted to familiarize myself with the car a bit before jumping in.

Fast forward: Last week, I had my RH valve cover off, investigating another issue (to be posted later). While the cover was off, there it was, my 2nd gen plastic tensioner, mocking me. I decided to buck up and get it done. Studied up on the tensioner change methods on this forum, ordered the parts, and got started.

On the RH side, the 2nd gen tensioner was cracked, as typical for this type. But it was still holding on.

Popped off the LH cover next, and was quite HORRIFIED to see a 1st generation plastic tensioner still in place...with 111,000 miles on it! One plastic shoe was completely gone, with the chain rubbing across metal (but no chain damage yet). The other shoe had a big chunk missing, and the tensioner body was cracked from top to bottom. Horror show images below.

There were no broken pieces to be found nearby, so I dropped the oil pan. Nothing much to see in the pan...because nearly all of the plastic bits were caught in the oil pick-up screen. It's a fairly large screen, so it was only about 25% blocked, but when I removed that oil pick-up pipe it sounded like a spanish maraca when I shook it.

Installed the new tensioners (zip-tie method), buttoned her back up and the car runs beautifully. A somewhat rough idle that had developed before the change now appears to be gone.

I'm feeling lucky. And I'm feeling grateful for this forum...I was thinking of many of you while I did the work. Couldn't have done it without you. Thanks very much to all of you.

 

You are a lucky guy, I'd suggest buying a lottery ticket!

 

Now that would put a smile on my face , knowing I got that close and averted disaster by the skin of yer teeth.... excellent well done.




And I would second buying a lottery ticket

 

Norri / XKRacer,

Haven't bought the lottery ticket yet, but I DID immediately go back into the house and make love to the wife. The day was clearly going in my favor.

 

Looks like the previous owner skipped some oil changes as well.
Attached is my engine with 60.000 miles

 

Yes, I agree. I was a bit disappointed with the dirtiness of the internals. I like things to be perfect, and I've noticed how clean many of the other forum member's engines are with the cam covers off.

But this is the engine I have, and I will take excellent care of it. I did clean up bits like the exhaust cam journals, the VVTs, and other things I could reach. Cleaned up the sump and oil pick-up pipe to spotless condition.

If anyone has any suggestions on how to best clean out a varnished engine like mine, I'm all ears.

 

Be carefull with putting 100% syntetic oil in if the car has always been driven with mineral oil.
syntetic oil will loosen, release the mineral oil sludge, which could then result in blockages.
suggest to add a can of sludge removal stuff just before you do you next oil change.

(By the way, my service record book is spotless. Not a single maintenance stamp during the last 10 years)

 

wow, horrifying indeed! Its new threads like yours, though there are many others like it on these forums, that will often give new and older owners alike, the ever-important wake-up call and reminder to not wait for maintenance so critical to the life of this 4.0 engine.

Great pics, truly shows the extent of the deterioration of that tensioner.

 

Just doing more oil changes might do the trick.

One time honoured method is to pour in a quart of ATF and run it before an oil change. The ATF has tons of detergents in it.

 

Wow, don't bother with the lottery ticket, I think you just used up all of your luck! Great pics, thanks for sharing.

 

I would seriously hope mineral oil has never been used, these engines should only ever have fully synthetic in them.

I also agree with plums, do some regular oil changes every 2000 miles for a little while and then work your way back up, eventually it will clean itself.

 

I can not see why synthetic oil would color the components to such an extend that even the cams are brown.
I have never seen brown cams before even with very infrequent oil changes.

Xkracer I believe you showed a similar picture in another post as well. Isn,t this the same engine by coincidence?

 

Nope, different engine. It would be my great pleasure to have XKRacer in my garage, or for my coupe to be in his. But alas, his shop is across a very wide ocean.

I've seen several photos in these forums of engines that look like mine. But I really get jealous when I see clean, shiny internals in other photographs. I'd really like to clean it up. I'll do frequent changes for a while, and try the ATF "just before the oil change" trick as well.

 

Mine was fairly brown too, like yours, when I did my tensioners.(both cracked badly but whole @ 65,000mi). So congrats on being aware and seeing for yourself what is going on. Bob is the oil guy website has enough info on engine cleaning, oils, etc that you'll have plenty of opinions and ideas to last a lifetime. I decided to go Penzoil Platinum every 5,000mi and will see what happens if I ever put the cam cover again. I'm not too worried. Maybe more highspeed running on my part will help, but that's when I always seem to get my Restricted Performance light flashing at me!

 

Coupe was correct, they were different engines. (One day I might have to have that busmans holiday )

The main reason is the lack of oil changes, the longest I would change oil is 6000 miles. But short journeys can also cause this to happen.

This pic has to be one of the worst I have seen on a running car, apparently it had a full service history.... yeah right!!! Done less than 90K miles




This pic shows what regular oil changes does for an engine,



This engine had done 70K miles and oil changed every 4000, and it was pristine, it's a close up pic showing of the secondary tensioner (2nd gen), I take pics of everything I do and email them to the customer so they can see everything that has been done or needs to be done.

 

Xkracer, that's a unique service that I am sure all your customers REALLY appreciate going the extra mile for their benefit and education. Your business model is what makes small companies successful. Ever thought about expanding to the US (hey, west coast customs did the opposite and went that way), think of the tax breaks and those 'business' trips you could take.

 

The manual in my 2000 XK8 dosen't call for synthetic.

 

mineral oil is as good or gives even better lubrication. but synthetic is longer lasting. and better resistant to temperature changes.
but it happens people leave mineral oil in for the next 20.000 miles and then you get sludge built up.

I even know persons who never change the oil and just do top ups. and yes, that even with a brand new car and never bring it to the garage for service during 150.000 miles.

 

When I bought my '98 XK8 in '06 it had 36k miles on it. The info from this forum made me have the dealer check the tensioners. I'm another lucky guy. They were ready to self destruct. Shop foreman said " you have to be very careful buying a low mileage car. The dry starts cause early wear on many of the moving parts". I use my car as a daily driver putting over 12K miles per year so dry starts are not a problem. What about the cars that hibernate for the winter, is there anything that the owner can do to stop this premature wear? Jack

 

Coupe, I have had good luck using a product called "CD2". It is an oil cleaning product, but pretty much it is straight detergent. it is safe to put into the engine right after an oil change, but I tend to use it for the last 50 miles before I change out the oil. This stuff seems to do a pretty good job at removing stuff. Used it on one engine that sounded like all the lifters were stuck (engine had not been run in 5 years) and even after about 20 minutes of running the engine, it still sounded like hell. Dropped a bottle of that stuff in and you could hear the valves quiet right down back to the purr that they should be.