chain tensioner...

[acf8181 0]

has anyone ever bled down the timing chain tensioner?

i'm following the instructions in the bentley manual but the piston does not appear to be retracting.

can someone give me there own way of doin it?

it's another example of german over-engineering...there's really no need for it to be this complex is there!

[jcorallo 0]

hey mate - just in from a night out on the town - hence why i'm posting at a stoopid time.

You simply remove the tensioner bolt, and stick a stiff piece of wire in the small hole on the end - whilst compressing the bolt down. This is the hole in the very end as shown in the Bently. The idea is that the wire presses on the valve inside and releases the oil inside allowing it to compress.

You can usually see a 'tide' mark on the bolt - which indicates where the bolt usually sits with respect to length. I usually compress it to just below this (shorter). If you compress the bolt too short, there is more of a possibility that the chain will jump the cam gear as the tensioner will be too slack when you put it all back together.

To be honest, the hardest bit is finding a piece of wire thats thin enough to poke through the hole, as well as being stiff enough.... I used a strand of wire from my B&Q wire brush....

Note that its easy for the wire to curl round inside the tensioner if you push too hard....

Jules

[acf8181 0]

gonna have to buy a new one now, as i teied using a sewing needle and dropped it inot the tensioner! oops!

[warwickA2VR 0]

I used one of those twist tie things (is that what they are called) after stripping off the plastic outer stuff. I couldn't find anything else thin enough. I dont think its necessary anyway and is dangerous to the engine.

Are you supossed to fit them fully pumped up to avoid the chain skipping of the sprock. Could you do this by putting it in some oil and sucking the oil in. How long should the tensioner be to avoid destruction of the engine on start up.

[ Edited Sun Mar 21 2004, 08:50PM ]

[acf8181 0]

i don't understand what i'm supposed to be tryin to achieve with this?

the piston is fully out at the mo, surely if i just put it in now, it'll be providing plenty of tension on the chain?

help, its pissin me off! (if anyone's near me, wanna come and help?)

[jcorallo 0]

not 100% on this, but if you were to install the tensioner with it fully out, you might literally snap the tensioner blade - but like I say, not 100% sure...

The thing I'm not sure about, is if you install the tensioner fully pumped out, whether it will automatically bleed down to relieve some of the tension on the blade???

You need to compress the bolt so that when you install it, the blade is pressing on the chain enough for it to not jump off when you try and start the engine for the first time. You should be able to see a tide mark yes? Well compress it to just below this as a guide and give it a go.

Jules

[FishWick 21]

Hi

I put a new tensioner bolt in my Corrado over the weekend due to the old one's leaking piston. Wasn't holding hyrdaulic pressure at high rpms.

They're £23+VAT

Anyway, best wire for bleeding is the centre core of some satellite/TV cable, or 22AWG if you want to be really precise!

The new bolts come fully retracted from VW and this would indicate it's plug and play but as Jules said, there is a risk of cam jumpage. Mine didn't jump but it's a risk you take.

I would fill the bolt with and bleed it set to 1" exposed length, this enough to give the upper blade a little tension and enough slack to actually get the bolt back in the head!

Cheers

Kev