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I have a 96 Polo Deisel which is rapidly coming up to 60,000 miles and needs a new belt. I have Haynes manual and job seems awkward but possible. Any general tips out there to avoid getting it wrong and crunching the valves, which would rather defeat the object.
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James:
One bit of advice, often quoted here is to change the tensioner and water pump at the same time. I had the tensioner changed at 60k with the belt on my Polo D, but never thought about the water pump until it failed at 72k. Luckily all it did was piss the coolant onto the A14 - the belt stayed in place. When I next have the belt changed I think I'll go for another new water pump!
I remember looking at the Haynes manual when the job ws due. In the end the VW dealer got the job because they quoted me a fixed amount of labour which sounded about 10 times faster than I could achieve the task. I'll try to dig out the receipt and let you know what they charged.
Regards
andy
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James,
You will need to follow the procedure carefully as it is possibly unusual in that the camshaft pulley is freed from the camshaft to allow it to float during the setting procedure, remembering to tighten it up afterwards!
You will need the tools to set the camshaft position at the rear, set the injector pump pulley to position and the one to apply tension to the tensioner pulley. I assume you will make up something for each of these.
You need to fully understand the way of setting the pointers for the tensioner setting, having done that the belt tension is to a fixed value and no tension gauge is needed.
Note there are slightly different procedures surrounding the injection pump sprocket and final re-tension for AGD, AEF, AEY/AHB engines or the 1Y type.
Finally carefully check all guide/tensioner bearings, don't just think are they OK for now but remember they will be on for another 40K+ for the life of this belt.
Do ask for further info.
David
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James,
Andy's reply is sensible stuff and recommended.
However, if you are *careful* it is possible to change the belt without freeing the camshaft (so without needing the special tools for locking the camshaft). You do need to be very careful and disciplined, however, and make sure you have *everything* lined up properly, and be sure that nothing moves (or if it does that you can put it back)! Always start with cylinder 1 at TDC (line up the crankshaft timing marks, however, when you remove the belt covers you remove one of the marks). The trick is to make sure that the belt has no slack from the driving pulley all the way to the last belt run when you fit it. One way to check would be to count the teeth between fixed points (marks that you could make) on each pulley, for example.
However, he 'floating cam shaft' method does ensure that the cam position is correct even if the belt 'stretch' and temperature coefficient is inconsistent.
Maybe the best advice here is if in doubt get a dealer or good independent to do the job. Don't shout at me if you get it wrong!
Martin.
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Whilst it may not work on this engine (and not if you are dismantling/ replacing a tensioner) I can remember someone suggesting that if you cut the old belt down to half? width with say a sharp stanley knife, you can then half fit the new belt easily ensuring that relative timings are the same. You then cut old belt and slide home the new belt. But I think that if I tried it I would make sure its set up correctly before I start just in case things go awry!
Any comments anybody?
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Peter,
A known and often mentioned DIY method. The advantage is for someone with a fear that they will muck up the timing settings.
Problems....
This assumes the old belt was correctly timed, I've come across cases where the old belt was one tooth out so you would replicate this for another 40K.
The new belt is mostly tighter than the old one so a element of force will be needed to stretch it over the sprockets/pulleys. A timing belt must never be forced. This assumes you keep the tension on the belt, if you release it to make it easier to slip over the new belt you risk losing the timing and the method fails.
Perhaps most important you'd be using this method because there isn't a complete confidence to set up the timing marks etc. Given the cost of failure I'd leave it to someone else if that is the case.
David
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Peter,
I edited a chunk out of the above before posting and I've just noticed one of the most important points went with the edit.
That "cut the old belt in half" method means that you neither intend to change or even check the tensioner/guide rollers/water pump (if in the system). Too risky!
David
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Put one dab of Snopake on every gearwheel and on the old belt at the corresponding points. Remove, lay new belt on top of old, copy dabs onto new belt, refit, lining up marks.
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Thanks to everyone who responded. This has given me a few more ideas. I will see how much I can get it done for at a garage. (including water pump)
I generally like to do things myself as you gain more experience and then can generally do more and more things. You also know the job has been done correctly. With timing belts there is litttle room for error which is why I sought advice.
If I do the job myself I will let you know how I got on.
Thanks
James S
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James:
Just dug out the invoice for my timing belt. I seem remember they quoted me 2 hours for the job. Actually charged 1.6 hours. So that will be £72 sir. Plus the VAT.
hth
Andy
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