Litens timing belt tensioner

[bob54321]

Hi All,

I've posted in the Fabia section as this is related to a Fabia 1.4 TDI PD but I've not had too many replies yet - I know this engine is pretty much the same engine as the 1.9 TDI PD in the Octavia. I just wanted some extra opinions....so if you wouldn't mind checking out:

My other post in Fabia 1 section

I'm worried that I may have fitted the tensioner incorrectly....this post here suggest you can even apply tension by turning it the wrong way:

http://briskoda.net/forums/topic/170550-litens-belt-tensioner-failure/

I cant remember which way I turned it...I'm sure that when I fitted it there was only one direction of rotation that tension could be applied. I do think that this Litens tensioner is very confusing.....whats the point in the having this thing spring loaded? You have to pull against the spring to get the correct tension then tighten the bolt to hold it there! Why not leave the spring out?

Your help greatly appreciated!

Cheers,

Matt

[rotodiesel]

See my reply to your original post. The Litens tensioner is a very clever design which rescued the PD timing drive - the original tensioner design was not satisfactory.

You turn the tensioner hub clockwise to tension the belt with the VAG 2 prong tool or a 6 AF hex driver - the hub will take either. There is also an arrow cast in the hub to tell you which way to turn it.

The pin is provided as a means of fully retracting the tensioner to make fitting a new belt easier (see my post). If you managed it without, no problem as long as you didn't crimp the belt.

These engines don't take kindly to inexpert maintenance - but on the other hand, VAG's instructions are not very bright either.

rotodiesel.

If you had turned the tensioner hub in the wrong direction, you would not get the pointer to line up with the slot in the back plate.

Edited 18 January, 2011 by rotodiesel

[bob54321]

See my reply to your original post. The Litens tensioner is a very clever design which rescued the PD timing drive - the original tensioner design was not satisfactory.

You turn the tensioner hub clockwise to tension the belt with the VAG 2 prong tool or a 6 AF hex driver - the hub will take either. There is also an arrow cast in the hub to tell you which way to turn it.

The pin is provided as a means of fully retracting the tensioner to make fitting a new belt easier (see my post). If you managed it without, no problem as long as you didn't crimp the belt.

These engines don't take kindly to inexpert maintenance - but on the other hand, VAG's instructions are not very bright either.

rotodiesel.

If you had turned the tensioner hub in the wrong direction, you would not get the pointer to line up with the slot in the back plate.

Thanks rotodiesel. You have set my mind at ease. I take your warning about inexpert maintenance - I have some experience, and can follow instructions...but not an expert by any means. Given the stakes (i.e. dead engine) I wasn't keen on making any mistakes - hence the concern raised in this post. I think that I must have tensioned the belt correctly - the pointer and the gap in the back plates alligned - even though in my inexpert opinion the belt seemed quite tight. The only thing that you've now raised cause for concern about is the torque of the tensioner bolt...I followed the VAG manual 20Nm + 45 degrees (using my halfords torque wrench). Also, there were replacement studs in the kit which I didn't bother fitting as the ones already on looked totally fine, but then I'm probably wrong!!!?

Still be interested to know why these tensioners are spring loaded?

Cheers,

Matt

[rotodiesel]

The tensioner is spring loaded partly to accommodate engine expansion as it heats. As the shaft centres move outwards the belt tightens. With a fixed tensioner as used on some other engines, the belt often has to be set too loose in order to end up with the correct running tension. This risks the teeth being stripped on start up.

On a PD engine, if you remove the upper timing belt cover with a hot engine, you will see that the pointer has moved about 5 mm to the right showing that the tensioner has taken up the expansion.

These belts should be run very tight - and the Litens tensioner allows this. It's a good design.

The VAG kit does not include studs - so I guessed you used the Conti kit which does. No problems with this but the tensioner instructions in the Conti kit are for the Rueville tensioner - and wrong.

If your stud did not show signs of pulling out as you finally tightened it, you're probably OK. I think the VAG torque figure is very marginal - and I've heard of several pulling out, some after a few hundred miles of operation. I suggest you gently check it with a 15 AF ring spanner after about 1000 miles. Be careful with it next time...

rotodiesel.

[Railroad]

See my reply to your original post. The Litens tensioner is a very clever design which rescued the PD timing drive - the original tensioner design was not satisfactory.

You turn the tensioner hub clockwise to tension the belt with the VAG 2 prong tool or a 6 AF hex driver - the hub will take either. There is also an arrow cast in the hub to tell you which way to turn it.

The pin is provided as a means of fully retracting the tensioner to make fitting a new belt easier (see my post). If you managed it without, no problem as long as you didn't crimp the belt.

These engines don't take kindly to inexpert maintenance - but on the other hand, VAG's instructions are not very bright either.

rotodiesel.

If you had turned the tensioner hub in the wrong direction, you would not get the pointer to line up with the slot in the back plate.

Rotodiesel

I did a cambelt and water pump on a Golf 2.0 petrol with a AZJ engine yesterday and on both the old and the new tensioner was an arrow clearly indicating it should be turned anti-clockwise. I thought about it for a moment because on my own TDi 110 ASV engine I distinctly remember turning the tensioner clockwise. Nevertheless I tensioned the belt on the AZJ in the direction of the arrow, and the pointer did line up and the belt seemed to be tensioned about right. I just hope it doesn't fail tomorrow or my boss won't be too pleased.