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View Full Version : two timing belt questions (1.8T)



Paul S.
10-10-2011, 09:26 AM
I'm doing a waterpump/timing belt job on a 1998 A4 1.8T AEB. A couple questions:

1) What are the torque specs for the "new model" tensioner pulley bolts? Specifically, the Bentley manual pictures the pulley as having a track groove that allows the pulley to swing around the dampener plate bolt, but the one I bought from the dealer just has a single threaded slot with no track for swing action.

The torque specs for the dampener plate bolt for the original model is 25Nm- but I imagine that amount must be higher than the new ones, since the "new" model doesn't have to keep the pulley from sliding loose along the track groove. What should I torque the bolt to?

2) I've gotten conflicting advice about the need for a new hydraulic tension dampener. Every kit and online timing belt install thread mentions the part (obviously to get the TB up to the correct tension/torque), but the guy at the dealer insisted it wasn't necessary. I have a new one ready to use, but I want to know, will the old one work as well?

Thanks all!

Snooter
10-10-2011, 11:25 AM
I don't know the answer to number 1, but I would always replace the hydraulic tensioner. More often than not it will be the tensioner that fails, not the belt snapping.

Duds
10-10-2011, 11:43 AM
x2 You might as well do it all while your in there.

xdewaynex
10-10-2011, 11:50 AM
Like mentioned, always replace the Tensioner...its usually the main cause of a failed timing belt.

BUSAfREAkA4
10-10-2011, 01:05 PM
Paul, def best for piece of mind. Replace the Tensioner. Were talking about a 60-70$? part that if it fails cause 1000's of $ of damage. Throw it on. As for torque spec's. I dont see why they would be different. Hopefully Mr. M Hood can lend his expertise, he's pretty knowledgable on these cars and I would trust his opinion.

Paul S.
10-10-2011, 01:41 PM
Awesome- thanks guys. I definitely don't want a headache down the road, so I'll be sure to put that tensioner/damper on.

walky_talky20
10-10-2011, 02:05 PM
While I haven't seen the tensioner be the "main cause" of belt failure (usually the teeth get ripped off from age, or low oil pressure locks up the cam), it is still absolutely necessary to replace the hydro tensioner. Almost every one I've ever removed has been at least leaking, or has started to lose tension at maximum deployment position. I just deleted mine.

Paul S.
10-10-2011, 03:13 PM
Thanks, Walky.

So does anyone know the torque amt. for this bolt:
http://www.audiworld.com/tech/pics/eng35-new_tens.jpg


(picture taken from AudiWorld's waterpump/Timing Belt DIY (http://audi-diy.blogspot.com/2007/10/audi-a4-b5-timing-belttensioner.html))

walky_talky20
10-10-2011, 07:35 PM
That bolt should be pre-installed. The green paint meens it's already been torqued. That piece is not available separately from the roller, so the torque spec is not available. I'd say 11 ft/lbs or so, maybe a spec more. And use some loc-tite.