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I had a look at mine yesterday and took a few pics. Not great pics, sorry. It over hangs the cam sprocket as your does. Can't see it but it feels like about 1mm. There is a slight brown discolouration on the outer edge but very minor. No fraying or anything. Can't see it ever taking out the belt.




You can see the discolouration in this pic.







Some idea's

Your tensioner bolt looks worn and tool marked. Was it replaced and torqued correctly? It's only 20Nm or so.

Have you tried turning it over with the damper and cam pulley fully torqued up and all covers fitted? I presume you have the inner and outer upper covers.
Up to you in the end but if I was in your situation I'd probably replace the tensioner and bolt fit everything and fire it up for a minute or two pull off the cover and check it again to see where it sits. Not much more you can do apart from replacing all the sprocket and a new belt kit with WP.
 

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Discussion Starter #23
Cheers for the input Interslice. The tensioner bolt just has marks on it from me using the vice grips instead of correct spanner. It's only the adjuster bolt and no damage. I have had everything put back together and torqued up correctly. As soon as I turn the engine a couple of revs the belt moves off the cam sprocket and rubs on on the middle cover plate. I intend to take some precise measurements tomorrow because either there is a problem with the cam sprocket or the crank sprocket. All looks and feels as it should. I need to know if all pulleys are running on the same plane I.e with no offset with each other. Something definately isn't right. If yours is running 1mm over the cam sprocket there must also be a problem. I intend to find the problem to this tomorrow ! Will definitely post back.....
 

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Looking at your 1st picture it looks like it may be an issue with the Cam end caps as someone mwntioned.

The end cap in the picture does not seem to line up with the end of the head, which i thought
it would usually. The cam seems to be to the right a bit as the first bearing area looks to be too far out
and the second cam lobe seems very close to the 2nd bearing cap.

Worth a closer look I would suggest.

Mike
 

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Discussion Starter #25
Glad you spotted that one Mike. Noticed that the cam looked shifted to the right, but this is as vw spec. Nothing changed. The cam and bearing caps can't sit in any other position. I thought this when I first spotted the problem with the belt. However, it doesn't explain why the belt is also rubbing the middle cover which is situated lower down towards the crank sprocket. If the cam was shifted left a bit it still wouldn't affect the belt lower down. It would look right from the top though! I would like to see other acv camshafts to see if there are any differences now that you have picked this up.
 

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Interesting to see how you get on with your measurements. It had crossed my mind that maybe the taper on the cam had worn or perhaps the pulley maybe but not by 2mm. 2mm of wear in steel that hard I don't think is possible, I think it would just crack or snap first. Maybe what you had planned, but i think a long straight edge across the face of the crank and cam sprocket and using feeler guages would be a good judge of the allignment of the four parts. A long steel ruler or one of those straight edges you would use for checking a head for warping, or a bit of 2x4 ;).

From googling 'timing belt rubbing cover' tonight, over and over again the tensioner is being blamed. A slight play in it's bearings, bent bolt etc. and it might push the belt slightly outwards against the damper pulley which holds it on. As you said it's the weak point.

Exact same situation here on a VAG 1.8t. - http://forums.vwvortex.com/showthread.php?3972082-New-Timing-Belt-rubbing-on-outer-edge

I think I'll be re-adjusting my cambelt timing at the 2 year mark now as they recommend and replacing the tensioner with a VW one. Might even do it a few months early this christmas.
 

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Discussion Starter #28
Firstly I'll ignore the last unhelpful, blunt comment.

Did some measuring today and found that the crankshaft sprocket does not run on an exact plane with the cam sprocket, water pump or tensioner. It sits approx. 3mm further out when the four allen bolts are tightened up. The allen bolts draw the crank sprocket up against the damper pulley, away from the engine. The damper pulley sits directly on the end of the crank, and this cannot move. It is possible for the crank sprocket to sit closer to the engine, be aligned in the same plane as the cam sprocket etc...but this would involve effecting some modification to keep the crank sprocket from being drawn against the damper pulley.


Why the crank sprocket is not aligned with the cam sprocket beats me. Is something missing? Is it the wrong crank sprocket? It is impossible to align the crank sprocket as no adjustment exists. It sits 3mm further out, which in turn pulls the timing belt 3mm further out, and in my case this is enough to make the belt rub the cover and overhang the cam sprocket. Next two photos show firstly where the crank sprocket could sit and be in alignment, and the second photo shows where the crank sprockets sits when the damper pulley is installed and all four allen bolts and the big stretch bolt are fitted.



You can see this further explained in the next two photos. The first photo shows how the crank sprocket would have to be in relation to the damper pulley for it to align with the cam sprocket. The second photo shows how it is actually situated when everything is fitted.
In this case it is not in alignment with the cam sprocket.



Finally with everything fitted correctly!!!and torqued up correctly!!! the belt resumes it's offset position:confused:


With a crank sprocket that is misaligned somehow, there is no possible way that changing water pump, tensioner, belt or even messing somehow with the camshaft will regain the true alignment of the belt.

Any helpful comments are very much appreciated.

Interslice....I hope this is helpful to you and my long winded approach makes some sense.
 

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The only thing I can think of is the crank main bearing thrust cheeks are worn away so the clutch operation is pushing the crank through the engine and out the other side by 3mm. I'm really clutching at straws here now!
I suppose a test for this is either try and drift the crank into the engine with a wooden block and mallet, or take out the flywheel timing plug and see if you can lever the flywheel towards the gearbox. If it moves any more than a fraction of a mm, then the thrust bearings are shot.
 

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Discussion Starter #30
Thanks bluezie, that would explain the crank sprocket misalignment. I will try this next. If I find movement in the crank, is this a big job?
 

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Just an idea but have you got the packing washers or shim washer fitted before you fit crank damper ? There is usually a pack of these with the timing belt kits ! Although 3mm does sound a lot maybe could save you a lot of work ! Also if you have got the old crank damper is the same thing happening ? I found on my bus the lower metal belt cover was fairly distorted making it sit closer to the belt ! There was cowboys working on mine though ! Good luck with it and hope you get it sorted without too much hassle T:
 

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Firstly I'll ignore the last unhelpful, blunt comment.
Short and sweet lol

All i'm saying is everytime I have seen this it is the Waterpump or the Tensioner .

I know they are new 5000 miles ago but that does not mean you can rule them out.

You may be onto something with the bottom pulley but not something i've seen before.

You can ignore that too - I don't care
 

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Short and sweet lol

All i'm saying is everytime I have seen this it is the Waterpump or the Tensioner .

I know they are new 5000 miles ago but that does not mean you can rule them out.

You may be onto something with the bottom pulley but not something i've seen before.

You can ignore that too - I don't care
That would have been my advice as well, but didn't bother giving it after such a rude response:eek:
 

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Discussion Starter #37
Look guys, I don't want to fall out with anyone on here. I apologise to Zmok for my uncalled for response to his post earlier. I completely took it the wrong way. Maybe easily done on a Forum with only typed words and no face to face communication. I live and learn, and a BIG sorry again to Zmok.

If I may go back to the problem at hand......

Tried my best to see if there was any movement in the crankshaft.....wooden block, heavy mallet (sledge hammer) etc.. Checked for movement at the flywheel. Zero movement. So I guess the crank main bearings must be ok!

The crank sprocket is still 3mm further out from the cam sprocket, water pump and tensioner. The later three are all aligned perfectly.
There isn't any play in the tensioner or the water pump. I've tried various methods to test for movement here...nothing!! I've tried taking all the tension of the tensioner, resetting the belt and turning the engine over again several times by hand.....the belt resumes it's position 3mm away from where it should be. If I try a new cambelt kit, including water pump at over a hundred notes, is it likely to counteract the fact that the crank sprocket is way off line?

The engine will run, but I'll have to ditch all the cambelt covers. Then there's the question of how long the belt lasts!

If anyone is in the middle of doing their cambelt on an acv it would be interesting to see how the crank sprocket is located and whether it is aligned with the cam sprocket etc...

Thank you all for the input.
 

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That's a bummer man. Hoped it was just the tensioner. I had a read through the cambelt procedure there on elsa win. Did you tighten the M8's first and then the M18. Reading the procedure it's the M18 first. I think I might have done it backwards myself last time. Looking at your pics it looks like the M8's pill it off the crank and the M18 pull it onto the crank. Very hungover so could be talking nonsense.
 

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No apology needed bud. I know it can be pretty annoying when you cant get to the bottom of something.

If your sure its not the waterpump bearing moving when the belt is under tension

I think then it might be worth trying another vibration damper - This pushes on the end of the crankshaft - maybe it is manufactured wrong? maybe its not the correct one?

You could even borrow a knackered one that someone has changed to see if it pulls the sprocket off again?

I know your belt is rubbing on the cover so there is something wrong there - but most t4's the belt runs on that side of the pulley and not in the middle like you would expect. How much does the belt overhang the pulley?
 

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Sorry thinking(just about) out loud a bit. Looking again I think it will be pulled out regardless. Could it be the wrong damper pulley I wonder. Clutching at straws a bit but at loss to more ideas really without pulling off covers and the damper pulley for a look.
 
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