Volvo 850 timing belt moving side to side, walking to one side

doviz86 · Post by **doviz86** » 12 Sep 2017, 12:38

Hello everyone,
So after replacing the timing belt kit (gates) along with water pump (hepu), (the only thing which I reused was hydraulic tensioner), I ran into a problem: after I started the car, timing belt moved from the middle of cam sprockets (where the old belt was running), to the edge of the sprocket, the one closer to the engine. I tryed to move it back, but all the time after starting the car it was walking back to the edge, and stayed like that, maybe the water pump pulley washer kept it in place from walking off the sprockets, the belt side was flush with the side of sprocket. I thought maybe that's the belt which is causing the problem, because I tryed switching back to the old tensioner pulley, and it was still walking to the side, so I bought another belt, Contitech one. After putting it all in place, I started the car, and it seemed to be okay, belt was running almost right in the middle of sprockets, the only thing I noticed is that it was moving side to side a little bit, maybe 1mm or so, and I don't know if that's normal or not. The same day I traveled around 60 kilometers with my volvo, and after coming home, when I removed the timing belt cover, I saw that it walked back near the edge of the sprockets, not so far as with gates belt, but close enough. I moved it back to the middle, rotated the crank and it was back in place, in the middle, so I guess it moved to the side after some harder acceleration, when it's on idle, it is only moving side to side a little as I stated before. Maybe someone encountered the same problem ? The only things which I suspect could be causing problems, are either the idler pulley or tensioner pulley, but I can't see any wobling. I even tryed to remove the water pump and put it back on, but it didn't help either. Pulleys, which came with the timing belt kit (gates), are clearly not INA, there are just some numbers on them, no logo or name.
One more thing, when I compressed the hydraulic tensioner, there was little bit of oil coming out, not that much that after tilting it to the side it would leak, so I think it's okay to use? And I don't really know how tight the belt should be, but when I apply some force, I can move it side to side on the cam sprockets by hand, is it normal? Hydraulic tensioner probably has 70 - 90 k kms on it and is 5 years old.
In a few days I will upload a video how it is moving side to side.

Post by **oragex** » 12 Sep 2017, 12:53

There's a guy with the same issue on the 2001-2009 forum. He's a bout to replace everything again, but someone said it may be because the belt was twisted in the package. Have a look

Post by **rspi** » 12 Sep 2017, 19:35

Post by **rspi** » 12 Sep 2017, 19:35

Post by **rspi** » 12 Sep 2017, 19:40

Timing belt parts are probably the most import maintenance parts to install on your car. The cheap route is the worse route. I have no idea why people buy cheap parts to save $50 on this critical maintenance. Get OEM timing belt parts and do it over. I am seeing a lot of timing belt parts failures with aftermarket parts. I mean within 90 days. It's not worth it. I mean, you are saving over $600 doing the job yourself, do yourself a favor and get good parts when the failure could trash the car.

Post by **rspi** » 12 Sep 2017, 19:42

How fast did you compress the tensioner?

Post by **cn90** » 12 Sep 2017, 22:03

Search forum, I believe someone else used Gates Timing Belt and had the same exact issues of the TB walking in and out of the sprockets. Not the end of the world but not a good sight.

Contitech TB does move from side to side a bit, and 1mm movement is normal.

Post by **sleddriver** » 12 Sep 2017, 22:18

Using anything other than OEM BLUE-BOX Volvo timing belt kit, is courting danger! Seriously! This IS NOT the place to skimp, cheap out, fudge, finagle, save money or otherwise.

I've experienced the TB 'walking' a bit off the front edge even using OEM parts. Check back through my posts to see photos. Scary. I stopped driving the car!

Before using any TB pulley bearing, put your ear on it and give it a spin. If it makes ANY NOISE, reject it! Been there, done that. Don't use it. It should be DEAD QUIET. NO exceptions!

Compressing the hydraulic tensioner needs to be done VERY SLOWLY to prevent ruining the inner seals.

doviz86 · Post by **doviz86** » 12 Sep 2017, 22:55

Before buying the gates kit, I read on several forums that it is good manufacturer, now I regret buying this kit, I thought it comes with INA pulleys.
I compressed the hydraulic tensioner slowly, as stated in Robert's video, a half or quarter of a turn every few minutes, and took a photo of it. It took me a hour or so to fully compress it.
One more thing, do I have to use some grease on tensioner pulley bushing before putting it in place?

Post by **scot850** » 13 Sep 2017, 15:37

was there a plastic cap on the end of the tensioner piston? The Volvo timing kit I used last time came with a new one in it. If the tensioner is leaking oil, then it is toast and maybe you are not getting the full tension to keep the belt taught?

As to your question on the pulley lube, I never used any but I can't see why a little would make any difference as the inner part of the pulley should not be moving anyway.

Neil.