Club 80-90 Forums

Hi all,

hoping some light can be cast on the latest “issue” I have come across.

I had the timing belt changed 18 months and 1500 miles ago by a “reputable garage” who also changed the water pump !!!
I have noticed that there is a fair bit of cambelt dust/fibre when I removed the cover to inspect. Straight away, I can see what I believe is the problem. The injection pump appears to be about 3 degree longitudinal out of alignment with the camshaft.
my question is, is this within any tolerance and how do I correct it and if necessary, how is it adjusted. It also appears that the belt has lost 3mm of width (this is a guess). When the belt disappears into the crankshaft area the belt appears, again, 3mm out of alignment (the belt is 3mm further forward than when it returns to the camshaft).
im hoping that the answers coming back will be “relax, it’s the way the Germans designed it”, “ it was installed by a mechanic at 4:59pm on a Friday”. 

thanks again, Rob

The diesel mechanical workshop manual is here:

http://syncrosport.com/info/manual/VW_T ... hanics.pdf
 

Hi Rdav1s,
Just wondering if you've found the answer, I got the same problem (just posted on here).
Cheers
Blakie

More than likely the Bush in the nose of the pump is worn. Does the pulley look out of alignment to the pump body?
Remove the belt and give the pully a good tug about, see how much movement you have.

I presume you’ve checked the rear mounting bolts tight? Just clutching at straws
 

The 1.9td in my old van was a bit like this, belt didn't run centre on the pump, seemed fine for the 7 years I had it and 2 differant belts. Although it wasn't rubbing anywhere.

From my experience with machine timing belts...if it is significantly out of alignment the belt will shred one side against the tensioner pulley, worse it will try to walk off the pump.
Toothed belts dont always run dead centre on all the pulleys but an angular error needs investigating.
Engine dropped/ fell over in previous ownership and bent brackets possible?

Method
Using a machine shop straight edge or similar. Hold the straight edge firmly across both the suspect pulley and the cam pulley.
You will be able to measure the amount of
of miss-alignment by placing feeler-gages, vernier, or calliper at each side of the pulley that protrudes the least from the block.
Turn the crankshaft through 360degrees and re measure.
The pump mounting bracket is Very strong, but you can remove the pump and check the face of the bracket to see if it is parallel in the same way.
You will need to remove the pump anyway to tighten the mounting bolts if that is the cause.
The thin metal backing plate of the timing belt cover is easily bent during engine change/ hoisting. This can often be confusing when looking at the belt in relation to the pulley.
That backing plate looks bent to me.
Fingers crossed that’s all it is.

Hi All,
Thanks for all the advice.
My belt is about 2mm off the bottom sprocket. I had the injection pump re-built in Jan as it was leaking, the pump started leaking again in a different place in Aug! and I then found the the belt shredded and cover melted.
I've never had a problem with the belt before the pump rebuild, and the mechanic can't figure out what the problem is.
Apparently no unwanted movement in any of the pulleys/sprockets.
I'll try the straight edge idea to see what's out, but all that's changed on my engine is removal and refitting the pump.
Any more idea's would be great

Sorry to hi-jack this thread!
many thanks,
Blakie

Did the pump rebuild involve a new drive end bush/bearing?
The usual cause of the seal on the nose of the pump leaking is the fact the driveshaft is being pulled to one side by timing belt tension, premature wear on the bush and then the seal leaks.

Hi mate I’ve just re-read your original post.
Can I suggest that you don’t start your engine until you checked the crank nut
These can work loose overtime causing chattering which eventually ends up in the bolt falling out of the end of the crank and catastrophic engine failure.
I’m not trying to frighten you just circumnavigate a major well-known problem.
I’ve not worked on the JX for quite some time, but remember this being a problem on both the JX and the AAZ crankshafts

Morning All,
Thanks ever so much for all the suggestions.
So I've finally managed to get up to the mechanic to have a look for myself (the bus is my daily). but it was wedged in against a fence and a car he was working on so couldn't 
So the belt is overhanging the oil pump pulley, not the bottom sprocket.
Mr. B- this time the pump was rebuilt with a new genuine Bosch drive shaft, and the nose bush was replaced.
Timburrows- bolts all tight
Footstuck- he said he'd checked with a straight edge 'the best he could' and all looked fine. Crank nut all good.
thanks again.
Blakie
 

syncroandy wrote: ↑07 Oct 2020, 21:51 The diesel mechanical workshop manual is here:

http://syncrosport.com/info/manual/VW_T ... hanics.pdf

Just joined the forum and this Workshop Manual is brilliant 

It hasn't helped with my issue but has given me some ideas with engine removal

Thanks for this

Blakefruid wrote: ↑12 Nov 2020, 12:05 Morning All,
Thanks ever so much for all the suggestions.
So I've finally managed to get up to the mechanic to have a look for myself (the bus is my daily). but it was wedged in against a fence and a car he was working on so couldn't 
So the belt is overhanging the oil pump pulley, not the bottom sprocket.
Mr. B- this time the pump was rebuilt with a new genuine Bosch drive shaft, and the nose bush was replaced.
Timburrows- bolts all tight
Footstuck- he said he'd checked with a straight edge 'the best he could' and all looked fine. Crank nut all good.
thanks again.
Blakie

If the timing belt is too tight it will run out of line,a good test is to hold it between thumb and forefinger and you should be able to twist it 90 degrees between injector pump and cam sprocket