Top timing chain tensioner

[Roger Blassberg 0]

Firstly, apologies to those who must have answered this many times before.

 

What is involved in inspecting/changing just the top timing chain tensioner? I think I understand that it can be done without dropping the gearbox and clutch.

 

There is also a lack of clarity in my mind about the use of Mk 4 parts; the car is a '94 VR. Can anyone help me with a list of parts required and their numbers? Advice on the advantages and practicality of using the Mk4 tensioner would be gratefully received.

 

Vince at Stealth had a listen a couple of weeks ago and said that it was not at all noisy, and my local specialist had a look last year when the top end was renewed, but I want to have a look-see myself in any case, particularly as recent threads have stated that wear is not always obvious merely by listening.

 

Thanks for your help.

 

Best wishes,

 

RB

[Kevin Bacon 5]

To have a really good look, you need to remove the rocker cover and the side plate the Cam position sensor is bolted to.

 

Before releasing the hydraulic tensioning bolt (27mm spanner / socket), check the span of chain between the two cam wheels for vertical movement. There shouldn't be any, or a very small amount depending where the cam lobes are pointing.

 

Now remove the tensioning bolt and pull the tensioner pad back and inspect it. You're looking for 2 deep scores in the resin pad and marks on the upper rivets. If neither present, you're OK. If the marks are present then you need to get it sorted fairly soon.

 

The upper tensioner pad and the tensioning bolt are the only items you need from a MK4.

 

I can't remember the part numbers, they're in here somewhere..... the pad ends E and the bolt ends B

 

The advantage of the MK4 pad is it's solid polymer, so when it does eventually wear, there are no resin coatings and rivets to break off and fall into the sump. The MK4 pad has shown virtually no wear on mileages in excess of 125K....

 

The MK4 tensioning bolt is sprung loaded aswell as hydraulic....so even if the hydraulic seal in the bolt blows, you have the spring as a back up and it also removes the need to bleed the bolt. If the bolt goes on the 12V engine (hydraulic only) then you get a loose chain and pistons hit valves and other such delights.

 

There are no disadvantages to using MK4 stuff.

[Roger Blassberg 0]

Thanks Kev,

 

Of course the $64 000 question is, "Can the top pad be replaced with the gearbox in situ if it is found to be on its last legs, or is it just the bolt that is easily servicable?"

 

Best wishes

 

RB

[dr_mat 0]

Sadly the answer to that question costs you $64,000.

I have heard of a guy who replaced the pad alone (not the actual tensioner, just the pad that's rivetted to it) without removing the lower housing (and therefore without removing the gearbox). But since part of the problem is that the chain itself has stretched, and you can't replace the chain without dropping the gearbox it seems a little pointless to not do it properly.

[Roger Blassberg 0]

Yes, I rather thought that it might..... Time to sell the children into slavery.

 

So it may be top and bottom tensioners and chains, plus a new clutch. Maybe a gearbox rebuild too as it has next to no synchro on 1st, is reluctant to go down into 2nd and whines in 4th.

 

Best wishes

 

RB

[dr_mat 0]

Sounds like you're beginning to get the hang of this Corrado ownership thing.

Of course us seasoned regulars in the Corrado repair game would say "hmm why not get a different final drive and a limited slip diff fitted while I'm in there"?

:lol:

[dazzyvr6 0]

do chains stretch that much though?the reason i ask is where i work there are chains running machinery,big gauge chains and small gauge chains,which are running flat out 24 hours a day,365 days an year with little or no maintainence,and coverered in abrasive saw dust and they very rarely fail :?

[jedi-knight83 0]

i always thought it was just the tensioners myself but if you going to all that effort of getting the box and engine dropped you may aswell put new chains in aswell....just for peace of mind.

 

chains dont stretch as far as i know...the look saggy if the tensioners have gone.

 

although im probably talking fudge :lol:

[dr_mat 0]

They do stretch. Most machinery doesn't have to do sudden stop/start cycles - the timing chains do.

By how much I couldn't tell you, but it's a contributory factor.

[dinkus 10]

If you've got it all apart, then change the chains as well, even if they haven't stretched much they're not gonna be in great shape after 10yrs of abuse.

 

You might as well do the clutch while you have the gearbox off as well. It'll cost you more initially, but saves a huge amount in labour if you never have to take the gearbox off again.

 

Anybody got any ideas how much a chain, Mk4 tensioners and clutch combo costs to get some at somewhere good like Stealth?

[dazzyvr6 0]

They do stretch. Most machinery doesn't have to do sudden stop/start cycles - the timing chains do.

By how much I couldn't tell you, but it's a contributory factor.

 

but onder a hell of a lot more pressure,and are stopping and starting as they lift tables up and down about 200 times a minute :)

[Kevin Bacon 5]

Yes the chains do stretch..... why else do you think the tensioner pads are hydraulically tensioned?

[dr_mat 0]

Around the £600-700 mark all in.

Most places assume 10 hours labour, and then you pay around £300 for the parts. Mk4 tensioner will save you £20 tho..

[dinkus 10]

Yeah I had £700ish floating around in my head. *joy*

 

I'm pretty sure my chains are fine, but it's worth being ready for that kind of expenditure...

[dazzyvr6 0]

Yes the chains do stretch..... why else do you think the tensioner pads are hydraulically tensioned?

 

 

and you think the ones in the machinery i use in work arnt? :)

[Kevin Bacon 5]

A saw mill and a car engine...... yeah I can really see the likeness :roll:

[dinkus 10]

A saw mill and a car engine...... yeah I can really see the likeness :roll:

 

Mind you, when a VR has got gammy chains it sounds a lot like a saw mill :lol:

[Roger Blassberg 0]

Mk4 tensioner will save you £20 tho..

 

Phew ! That's a relief !!

[dazzyvr6 0]

A saw mill and a car engine...... yeah I can really see the likeness :roll:

 

only a 4 million pound machine thats all,run by the same sort of chains,runs a lot faster,under more pressures etc..

[Roger Blassberg 0]

That "new engine for £1 750" rumour is beginning to sound more and more attractive.

 

Best wishes

 

RB

[dazzyvr6 0]

That "new engine for £1 750" rumour is beginning to sound more and more attractive.

 

Best wishes

 

RB

 

 

so whos going to be brave and pop into the vw dealers and ask about a new vr6 engine then :) and wether they are 2.8 or 2.9

[Kevin Bacon 5]

Check with C&R in Nottingham first as that price does seem *very* cheap.... Steve Cresswell is the man to talk to.

[dav 0]

just rang my mate at VW and he say the

 

£3620.83

 

Plus a sur-charg £1520.00

 

:roll: :x

[dazzyvr6 0]

just rang my mate at VW and he say the

 

£3620.83

 

Plus a sur-charg £1520.00

 

:roll: :x

 

ouch...just emailed c&r so ill see what they say :?

[dr_mat 0]

just rang my mate at VW and he say the

 

£3620.83

 

Plus a sur-charg £1520.00

 

:roll: :x

 

Why the .83 ???

 

Presumably that's a nice round figure when translated into Euros...?