Lower Timing Chain Tensioner VR6

[Fluff 0]

Hey there folks, can you help? I have a '95 Classic Green Storm with 70,000 miles on the clock that is in great nick, but makes a tapping noise on cold start that can last for couple of minutes. Worse with cold weather too... It's had new tappets, oil pump and upper tensioner.....the AmD verdict is that it is the lower tensioner....so engine out job :shock: Bloody VW designers! Has anyone else had this problem....? Wasn't expecting this for another 50K.....

[dr_mat 0]

You've spent some serious money there... :(

It's not unheard of, but the good news is that if you can put up with the tapping and rattling the chain is unlikely to ever actually *break*. Worst case scenario is slipping a tooth so the timing goes out.

AFAIK you can replace the lower tensioner with the engine in the car, but you need to support the engine on that end as it's no longer supported by the gearbox mount. You definitely have to have the 'box off though.

I'd be interested to hear how you get on, as mine makes similar noises and I had put it down to the auxiliary belt tensioner.

Mine has 116k miles, by the way...

[Fluff 0]

Hey thanks for the quick reply!

Yeah more dosh than I'd have liked.....but I love the car and want to keep it for good....so wanted it to be healthy going forward. The noise is driving me nuts I have to say and is getting worse (lasting longer). Used to happen for a couple of seconds, now it can be for 3 minutes. When you think it's gone and pull off, it reappears when the engine is under load, but then is gone completely after another minute or so. It pretty much went away in the summer, but came back with a vengeance when the weather turned cold. I've had the car for a year, and the previous owner was London based, and although it is in v good nick......it did need a big service when I got it. AmD suggested leaving it for another 10K until the clutch needs doing, but I am nervous about this just because it is getting worse. Do you know how common it is for tensioners to go at 70K? Will keep you posted for sure, but currently trying to find a local (trusted) garage to do the work. Oh hey, don't know wher I could get a new headlight do you mate?

[dr_mat 0]

The opinion of the group seems to be split 50/50... Some people say the tensioners are gone at around 80k in pretty much all cases, some say what about my 160k engine then?

As usual, it's really down to how the car has been driven and maintained.

The noise you're describing, however, could also be a touch of piston slap (I think Kevhaywire mentioned this as a possible).

Everyone is agreed though that the timing chains VERY RARELY break. Even completely shot tensioners will be very unlikely to result in any long-term damage. But if you're having the clutch replaced (pretty short life for a clutch, 70k!) anyway, it is definitely worth getting the lower chain and tensioners done at the same time.

In other words, unless you're feeling exceptionally wealthy, leave it till the clutch is done and learn to love it.. ;)

[dr_mat 0]

Oh, headlight? Um, ebay might come up trumps, but try gsfcarparts.com or gpcvwaudi.co.uk. In fact even the stealers may be able to supply just the glass for not too much dosh.

[Fluff 0]

Hey thanks again mate!

I did ask nathan at AmD about piston slap and he gave me a firm "no way, not on such a low mileage engine" Is this a serious liklihood then? I guess there isn't much you can do about that, and if I did decide to have the tensioner done, I'd be right miffed if it still makes the noise. Are there any other clues that would suggest piston slap? :D

[dr_mat 0]

Better ask kev, I'm sure he'll be along here sometime today...

Best thing - don't worry about it. Just drive it carefully while it's cold and the oil is EXTREMELY thick (I hope you put the oil temp on the MFA when you start the car and keep it down to 50% throttle and 50% revs till it's warmed up??).

Hey, do what a few people here have suggested: get a louder stereo... ;)

[PhatVR6 0]

Have you tried removing the upper tensioner and bleeding it?

[Kevin Bacon 5]

Have you tried removing the upper tensioner and bleeding it?

 

You mean the big bolt on the tensioner cover? Thought it was just a big spring?

Fluff, don't stress about it mate. You WILL know when your engine is need of some major surgery. The VR6 engine makes all sorts of weird and wonderful noises but if none of them affect the performance or running, don't fret about it. Mine sounds like World War 2 under the hood for 5 mins and then all is serine and peaceful, but I know for a fact my tensioners have loads of life in them yet, so I don't worry about it.

 

The noise you describe at idle.....is it a knock, clack, whack, bang, thump or wallop? Mine does all of the above but 3 things can cause a knocking when stone cold - camshafts and pistons. (3rd outruled as you've done the tappets already).

 

Listen to pretty much any petrol engine, even brand new ones and you get a little camshaft or piston knocking for a short period until some heat builds up and expands the metals.

 

Again, nothing to worry about. Piston slap and camshaft rattle are only worrying noises when the engine is hot!

 

Kev

[Fluff 0]

Hey guys, yeah the noise itself is a clack probably? Most who have heard it have said tappets without hesitation, including me first time......but they were replaced and it made no difference. What else makes a tappet like noise at cold start, that aint the tappets? Timing chain in the guides if not fully tensioned? Thanks very much for all the good advice by the way, can't believe I haven't found the forum before now! Doah! Car I had before this was a 6 cylinder beemer, so by comparison....this sounds like a tractor when cold :D ....but so much better though!

[PhatVR6 0]

Big spring? LOL! it's a hydraulic tensioner. It has an oil feed, which presures up a chamber in the tensioner, thus pushing out the centre portion, which in turn presses the upper blade onto the chain. Air can get trapped in the tensioner. you have to remove it, immere it in fresh oil, pull the centre bit out (but not all the way) the take it out of the oil and hold it vertically upwards. poke a fine bit of fusewire down the hole in the end to open the one way valve, and it'll allow the trapped air to escape. then refit it without spilling any of the oil in it of letting nay air back in.

 

Try it, it usually quietens chains down a treat.

[PhatVR6 0]

Could I just add that my first VR6 does due to a failure of the tensioner and the upper blade. THere was a tear in the seal, which meant that the tensioner wouldn't hold the oil pressure, and wasn't holding the blade tight enough. The balde was flapping about, and eventually, th anti-friction coating came clean off! (I found most of it in the sump) and it was running on bare metal. Eventally it jumped a tooth on the back cam, causing it to run rough as sh1t. At the time I didn't knoe anything about VR6's, and took it to a "specialist", who diagnosed the poor running to bad injectors. I took them out, had them untrasonically cleaned, refitted them, only for it to run like sh1t still. Eventually, it slipped another tooth, and bent 6 valves in the rear bank. The head was trashed. That's when I first noticed the state of the upper blade.

 

Needless to say, I've check my other 2 VR motors, the one with 50K on it is OK, but the 110K one has a worn upper blade, which will be replaced shortly before it's sold.

 

Don't ignore engine rattles, listen to them and work out what they are. don't leave your engine to kill itself. Or you'll do this ----> :mad:

[Fluff 0]

Mmmmm......well both AmD and a local performance garage have now heard the noise and have said timing chain tensioner (lower).....and recommend new chain and guides too while I'm at it. The local garage even rang VW :shock: ...who's chief technical bod said the same thing (?) even though it's only done 70K.... The noise always goes after a few minutes and I'm always gentle with the car until it's warmed up so hopefull. One more clue..??.....if you increase the revs a little when it's doing it....the noise goes away......

[corradovr6sc 0]

Sounds like slack in the chain as they can stretch too. A mate replaced both his upper and lower tensioners but used the old chains but the cam timing was still out. Probably best to replace the lot as its not a job you want to do twice.

[PhatVR6 0]

Well if it's dependant on temperature, and thus oil viscosity, how can it be the lower tensioner, when that is spring loaded, and not oil filled like the upper one?

[Fluff 0]

Um...yes I had wondered this too as I alwyas thought that the lower tensioner wasn't hydraulic..?? Another clue is that the car has just had a service, and after an oil change the noise was worse than before...i.e. lasted for longer before going quiet...??? Couldn't temperature influence the lower tensioner too though? .....expansion/contraction of components? So I guess the bottom line question is.....if it sounds like tappets but isn't, is the chain rattling (for whatever reason) the next most likely candidate?

[PhatVR6 0]

I doubt you hear the lower chain rattling.

 

Get under the car, see if it's worse from underneath. Worth a try?

[dr_mat 0]

If the tensioner is a bit knackered, I don't see why you wouldn't hear the chain rattling. I wonder how much the engine block changes in size between 0 degrees and 100 degrees too? Probably enough to make a difference to the tension on the chain I'd wager.

[Kevin Bacon 5]

Big spring? LOL! it's a hydraulic tensioner. It has an oil feed, which presures up a chamber in the tensioner, thus pushing out the centre portion, which in turn presses the upper blade onto the chain. Air can get trapped in the tensioner. you have to remove it, immere it in fresh oil, pull the centre bit out (but not all the way) the take it out of the oil and hold it vertically upwards. poke a fine bit of fusewire down the hole in the end to open the one way valve, and it'll allow the trapped air to escape. then refit it without spilling any of the oil in it of letting nay air back in.

 

Try it, it usually quietens chains down a treat.

 

Good man! I might try that one dry weekend as my upper tensioner makes a curious grinding noise when cold but goes when hot.

 

Kev

[Kevin Bacon 5]

Mmmmm......well both AmD and a local performance garage have now heard the noise and have said timing chain tensioner (lower).....

 

They would wouldn't they as it's a gearbox off job....meaning more ££££s!

 

I wouldn't expect a 70,000 miler to be in need of a lower tensioner and chains, but as they say, stranger things have happened!

 

Kev

[Kevin Bacon 5]

Car I had before this was a 6 cylinder beemer, so by comparison....this sounds like a tractor when cold :D ....but so much better though!

 

My old 6 cyl Beemer sounded like a tractor when cold too! I've had 3 of them actually and none of them were as smooth or quiet as the VR6, not even the 24V.

 

Kev

[Fluff 0]

The thought had crossed my mind too Kev. However, spent 15 mins on the phone with Vince at Stealth yesterday.......who said the same thing. He had more good news for me too......basically if VW had stuck the 2.8VR6 in the Corrado aswell as Golfs, Passats and Sharans (boy do I need a beer after saying that!) instead of a 2.9 version....us C owners wouldn't have much to talk about..... Mmmm...maybe the answer is to go for the 3.1 conversion....?????

[PhatVR6 0]

If you have a VR6, you NEED a Shrick VGI. If you've never experienced a VR6 with one fitted, then I suggest you do as soon as you can. The low down torque is fantastic. They should have been like it from the factory.

[VR6 0]

....and if you find any hens teeth on your travels as well .... ;)

 

Would love a Shrick - don't know of many people that wouldn't tbh.

 

Unlikely to happen tho :(

[dr_mat 0]

Of course we all want a VGI (or even preferably a VSR). But back in the real world, we're not going to get one.. :(

Most of us spend so much money keeping our C from getting worse, that the thought of spending money between the spending of money, with the aim of making it better is just out of the question! :)