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neilw wrote:Yeh its still under warrenty.

They've just phoned me, The cam belt tensioner has collapsed and made the timing 4 notches out, and my waterpump was leaking. There waiting for a new waterpump to arrive so they can turn it on and test it out.

You know, when ever they screw with the cambelt they usually break the water pump, not the other way round. You are lucky with the cambelt only slipping 4 notches. Any further and it would have been scrap. Have the removed the head to check for damage?

I dont think they removed the head, had it back afew days now and its running just as well as before.

Yes I know, but the valves could have been damaged. Even if it runs ok, they could fail at the end of the stem. I would have preferred them to be fully inspected first to check any sign of collision at all. They run square to the piston, you can get away with it.

But you have been quite lucky so far, its probably ok. There isn't much else you can do.

How many notches are there?

What is the timing set to?

If there is slip of 4 notches, how much does this affect the timing? Does it make it 4 degrees out? If so, this will run bad. If it's too many out, then the first thing to go normally is the head gasket I was told.

We'll need this sort of info to make a case for the sort of engine damage that can be expected.

I think it means 4 notches or teeth on the cog. not sure how many there are in total. My entire engine was shuddering on it mounts when it was turned on. If its too far out the Pistons will colide with the valves at what every RMP your doing. so at tick over they'd be slamming into the valves about 16 times a second, which would clearly cause all sorts or damage. Thats my faily limited understanding of it anyway.

Well presumably it slipped 4 notches to make it retarded valve timing. As the camshaft are driven they will be behind.

Its very difficult to say but 4 teeth is probably about 20 Degrees. 4 teeth is about an inch on the sprocket. Clearly a very bad thing to happen and slipped that far, it cannot be much further to be getting into a collision. The usual problem is that the camshaft stops and the crankshaft doesn't and in a 4 cylinder engine one valve is always open. By how much and how much the overlap is is anyones guess. I have turned an interference engine over (from a 1.4 Mk4) with the camshaft stationary and it didn't touch, but with driven hydraulic tappets and high RPM's I wouldn't bet on it!

This is a good start. One spocket move is enough to put the timing out enough that the engine is severely impacted in terms of timing and valves opening and closing. If this sprocket notch puts the timing out an expected 5 degrees, then even if the timing was set at 12 degrees, this may be enough to cause severe engine damage.

I think we have enough information to go on to make representation to VW Customer service that the cambelt tensioner collapse is a severe problem that could compromise the driver's ability to control the car and could thereby cause an accident, particularly if driving at high speed.

And, the cambelt tensioner part should not be failing after 35K miles as has been seen on this forum, especially when it is to do with the cambelt particularly, which such a fundamental part to the stable running of the car engine.

Can we get this thread stickied?

Can we get something drafted to VW Customer Service and list all names on this thread, who want to have their name added to the letter, as being concerned parties? If we write a letter, VW cannot ignore it and it will have to be escalated to VW Technical.

I fully agree - mine went at 42k - made a complaint but never heard anything from it. I don't think I'm going to get my £400 back, but I'd like to think that it won't screw everyone else up.

It's all about presenting the issue with everones details in one go, they've listened to us once with the pedal box, maybe it'll work again!

Just for info, they'll always (sorry, they should always) change the cambelt doing this kind of work, as it's only a couple of quid for the part. My waterpump was changed as well when they did the pre-tensioner. I didn't mind, as it wasn't too expensive to do on top of the work already done, but surely this should be noted in the complaint as well, as there is obviously a issue with it (either in it getting damaged with cambelt removal or premature wear)

Woody

They did replace my cambelt in the end. I guess its just common practace

How do we get this sticky? I can start something if someone tells me what I need to do to sticky it. Thanks.

You can request one of the mods to sticky a topic for you, thats how we got the B&M GB stickied anyway.

Get it stickyed and get the name changed to Cam Belt Tensioner