Author Topic: timing belt tension ? (Read 5111 times)

DieselMonkey · « **on:** August 19, 2005, 12:42:35 pm »

Guys,

I've fitted several t'belts to VW 1.9's before without any problems, but today when fitting one to my Golf AAZ, it occured to me that i havent ever tightened the belt to any specific tension, by the book as such. I always get it as tight as i can, and this usually allows the belt to be twisted about 30 / 40 degree's between cam pully and pump pully.

Is this about right ? Put a lot of cash into the latest project, so i'm not leaving anything to chance.

can anyone give me the 'by the book' advice ?

Also, whats the worst that can happen on our VW diesels from an over tightend belt ?

thanks in advance,

Regards, DM

Maarten · « **Reply #1 on:** August 19, 2005, 02:18:50 pm »

Your belt will wear down faster and the bearrings of the pump and camshaft will start to hum and wear down too..

DO NOT tighten it as tight as you can because that is way too much.. best option, buy a belttension measurmenttool like this:

http://www.tensionmeters.com/belt.htm

DieselMonkey · « **Reply #2 on:** August 20, 2005, 01:44:26 pm »

Guys,

I checked the 'book'....

I had the semi automatic tensioner with alignment marks, the one where you line up the notch with the slot. I had read about that some time before, but it hadnt occured to me when tensioning the engine the other day.

So i looked at the tensioner and i have tightened it very very slightly passed the notch, only 0.5 mm or so too much, so i'm quite happy to leave it as it is. The workshop book also says that the belt should be able to rotate 40 /45 degrees between cam and pump. By eye i am pretty sure its in that area.

Also, the tool i use isnt great, and its short handled, so it makes it quite hard to tighten. With a longer handled tool, i'm quite sure i could have tightened the belt much more. The effort required to tighten to the degree i have it now was such that i thought it was over tightened. The same effort with a longer handle would have been way off the mark, if you know what i mean.

40 / 45 degrees ...Does this sound about right ?

Thanks for the input, Much appreciated. DM

Maarten · « **Reply #3 on:** August 20, 2005, 05:38:21 pm »

I've bought a special tool for the pulley, costed about €15 but makes it a lot easier to tension the belt.

Midlock has 2 versions, one has a much longer handle than the other.. the long one doesn't fit a mk1 enginebay with a TD engine

lord_verminaard · « **Reply #4 on:** August 21, 2005, 08:43:55 am »

I had a problem with belt tension on my 8v gasser, noticed a funny sound when the car was running, sounded like a supercharger even.

Realized I had the belt too tight. It's hard to judge what turning the belt 90* feels like. I mean, if you have giant ogre-hands it wouldnt take much effort to turn the belt 90* or more, but if you have girly hands it might take a lot of effort to turn it that far. I guess it's a matter of feel. Though the Diesels require more tension than the gassers do, right? I used a curved pair of snap-ring pliers to tension the belt, worked better than I hoped. (and obviously easy enough to over-tension the belt!!)

Brendan
84 Scirocco 8v
00 Camaro L36 M49

ricosuave · « **Reply #5 on:** August 25, 2005, 07:42:17 pm »

remember to adjust the tension when the engine is cool as well, not warm, and not hot.

in case it isnt obvious.

rico