toothbelt jumped over

[max_s2]

Hi.

First of all hi havent been here for few months since last year

So.. to the problem. My VEMS'ed S2 ABY has been left underiven for 2 months beneath the sky where air temps are -20c to -5c snow including. After that my S2 failed to start. The problem was toothbelt that has jumped over 4 tooths. I have no idea why it has jumped, but after fixing it car was again running.

After this all car again has left undriven for 2-3 weeks. Weather conditions -10c to -3c. Car started well without any problems and has been driven for few days. Yesterday, after my S2 has been left underiven only for 3 days in the same weather conditions, car didnt start. Again 4 tooths, but this time valves are dead

Questions:
1) Any ideas why this could happen TWICE and only this time valves gone bad?
2) Could it be because I have no front toothbelt cover? Many people run theyr S2 without it.
3) How much costs new valve? Is it good/bad to install used valves and how much should cost used ones?

Thanks.

[DJones]

Hi.

First of all hi havent been here for few months since last year

So.. to the problem. My VEMS'ed S2 ABY has been left underiven for 2 months beneath the sky where air temps are -20c to -5c snow including. After that my S2 failed to start. The problem was toothbelt that has jumped over 4 tooths. I have no idea why it has jumped, but after fixing it car was again running.

After this all car again has left undriven for 2-3 weeks. Weather conditions -10c to -3c. Car started well without any problems and has been driven for few days. Yesterday, after my S2 has been left underiven only for 3 days in the same weather conditions, car didnt start. Again 4 tooths, but this time valves are dead

Questions:
1) Any ideas why this could happen TWICE and only this time valves gone bad?
2) Could it be because I have no front toothbelt cover? Many people run theyr S2 without it.
3) How much costs new valve? Is it good/bad to install used valves and how much should cost used ones?

Thanks.

Strange..

There is no way a belt would move by four teeth when stood up..

Sounds to me like a wood ruff key top or bottom has gone missing from a loose pulley.. Check all your pulleys pumps etc too.

Don't use second hand valves and make sure you grind them in.

Hope it helps..

[driftin jo]

It could well have something to do with the fact you have no cover for the belt .
I have seen a lot of people run without them but it always seemed daft to me as it only takes a stone or other road debris to get in there and bang there goes your engine!
Other possibilities are something jamming the cam, I one saw a cam cap nut come off and wedged itself under the cam ,that made the timing belt jump!

The other thing that comes to mind is , have you got enough anti freeze in there ?
If the water at the water pump froze this could make the belt jump as the pump would refuse to turn .

[max_s2]

Thanks guys.

Anti freeze is tip top, brand new. Toothbelt brand new, so the tensioner (or how it's called). I hope soon to get the head off and check how bad everything is.

[Gringo]

I`m guessing you didn`t use the parking break but left the car in gear? If you do and the car rolls slightly this will slacken the toothbelt. In subzero conditions the belt is stiff and hard with less friction and grip. The sudden jerk of the startermotor could tug the toothed belt over several teeth. This is so far only a theory of mine. For practical reasons this is not something I have wanted to test. During our last winter trackday a few weeks ago, three cars had their cambelt jump several teeth.

[max_s2]

Guess whats missing of this camshaft gearwheel? This is what fcked up my engine
Maybe someone has one for sale (its for an ABY)? Or its better to buy a new one (~35euros)?

[rash]

35 EURO ?? I would by a new one...

...I have a complete set of valves (used but fine) if you need some...

[JP]

Max S2 looks like pulley been undone or done up with impact air gun at one point in it's life or not torqued up correctly with a fresh bolt. Seen same problem happen with crank pulley before where casting is brittle and breaks of from impact of air gun. Be worth checking that too whilst you have engine apart.

[max_s2]

I think that top pulley has been undeone for the first time. However, in summer I changed toothbelt and everything was OK with the bottom pulley.
Has anyone had ever problem like this when the top pulley fails?

[max_s2]

Better quality of failed pulley.

[newsh]

There have been many cases of these pulleys failing, so much so that common wisdom here is to fit a new one if you change the belt or disturb it for any reason. Its essential to follow the correct procedure for tightening the pulley.

[kenoid34]

My crank pully sheared it`s key when i let off the throttle on near full chat which then caused the key to shear on the camshaft pulley resulting in 10 bent inlet valves so it is now an ongoing project