Do your pullies wobble?

Next time you are looking at your engine idling, would anyone kindly make a mental note whether the cam belt spring tensioner that sits next to the alternator jiggles up and down - and let me know. My car is a 96 Golf TDI. At 180,000km, my crankshaft sprocket (that drives the cam belt)became worn (on the inside flat) and was replaced. 2000km later the bolt holding it on broke and damaged the engine valves.When rebuilt, the pullies that bolt on to the sprocket wobbled slightly at idle. A second new sprocket (all genuine VW)was fitted and a new harmonic balancer. The crankshaft end was checked for wear and was OK. The mechanic tells me that all these engines have a slight wobble and I should not worry about it but I am not so sure given the previous failure. The tensioner jiggles up and down probably about 5mm (1/4 inch) in total, but is steady when the engine is revved up. I cant remember what it was like before the problems. Thanks

I could be wrong, but I believe the tensioner next to the alternator is for the serpentine belt that drives the alternator and a/c compressor, not the cam. I don't think you can see the timing belt tensioner without removing the cover.

And yes, my tensioner moves quite a bit at idle.

Mine wobbles too and I was wondering if this was causing a noise and alternator light problem I have had twice now. On two occasions I notice that my charging system or "battery" light on the gauge cluster illuminates and I hear an odd metallic grinding/clanging noise coming from under the hood. The first time, I was able to pull over and look under the hood but it was dark and I didn't see anything out of whack. The second time I was unable to pull over and inspect. It only lasts for a minute or two and then goes away but it is definitely is coming from the belt and pulleys area. Anyway, if anybody else has had this problem please let me know what you found out. I first thought that it was the tensioner going out because I saw the bouncing tensioner roller described above and thought that possibly kept enough tension off of the alternator causing the warning light to illuminate.

TIA

I had those symptoms three weeks ago and they were consistant with a cold engine. I pushed down on the serpentine tensioner and it hasn't repeated the problem so far. I have 78,000 miles so I would assume that the car is telling me to change its belt and tensioner.

thanks avitech10 and the others, I feel better that it seems to be normal and yes, you are right - I am talking about the serpentine belt which is driven by the pullies. The pullies are attached in turn to the sprocket that drives the cam belt (with its own tensioner). Sorry for the muddle-up

Another mistake by me, I particularly meant thanks jck66 and the others. I was also going to say that I hope avitech10 was talking about the charging problem and not the wobbly pullies when he said that pushing down on the tensioner gets rid of the symptoms. Good luck Rogerpemberton - I havent had that happen so am unable to comment.

I found out today that the tensioner damper is a spring. That would explain the metallic noise I was hearing. I assume that whatever design elements were used to keep the spring immobile have failed after 244,000 miles and occasionally the spring bounces/spins around in the housing. Anyway, I replaced it today and I have noticed practically no bouncing of the tensioner roller. All that I saw was what I would characterize as vibration. Before it would bounce around an inch or more. Maybe it's my noodle messing with me, but I seem to notice that it runs smoother now too.

Hi Roger ,

I seem to have the same problem, my tensioner bounces all over the place, and when under load i get a harsh sqeaking noise, especcially when the power steering is engaged, i have 90K miles now so i assume it is due a change.

On question has anyone changed this on a A6 / Passat as its right at the front behind the radiator, i know you have a Jetta but how difficult is it to change.

Thanks in advance for the reply, any advice gratefully received.

C

On the Jetta you must take the belt off the tensioner roller and then remove three bolts. There are two holding the tensioner to the bracket and one in the center that connects the rod to the tensioner. The rod will only go into the tensioner one way and that is why you must remove the the belt from the tensioner so that it is not under strain. Also, make sure you note the orientation of the tensioner on the car before you remove it. You will see how the metal body of the tensioner is stamped. There is an offshoot or lip visible on the back of the tensioner that, I think, you must orient the same way as the original in order for it to work properly. If not, I did it anyway. Good Luck

SteveH,
make sure the bolts holding your harmonic dampner are the same length/proper length.