My s/c drive belt is jumping.... ?

[LAFENGAS]

Cliff Notes below.

Last year in the fall, my drive belt started squeeking pretty bad and it was rythmatic. I would spray some silicon on it and it'd go away for a little while (10-15mis, sometims longer) then the squeek would come back.

Like i mentioned, it was rythmatic..not with engine RPM but with Belt RPM. I put the car in storage for the winter, figured i'd worry about it come spring.

I went to change the belt, and noticed my water pump pulley had excessive play in it, so i also changed my water pump. Put a new belt on and instead of squeeling, now it's jumping 1-2 ribs off my S/C drive pulley...rythmatically (at idle, aprox. once a second).

This only happens when the engine is cold, then it seems stops jumping.

I have the ESS VT2 supercharger and have the UUC underdrive pulleys and my belt length I replaced with is 85.5" (that seemed to work well with the tensioner)


CLIFFS:

1.) replaced rythmatically squeeky belt
2.) Found water pump going bad, changed that too
3.) Replaced drive belt with new
4.) Now my belt is jumping off the S/C drive pulley aprox 1-2 ribs
5.) no visible sign of pulleys being out of line


Any Ideas? Has anybody diagnosed a similar problem? S/C bracket warped or known to move?

would like some input before i start ripping everything apart.

[TaZaM3]

Its probably the tensioner.

[LAFENGAS]

Its probably the tensioner.

in what regards? that it's not tensioning properly or that it's binding up? Is it common for the tensioner to fail?

[LagunaBlau///M3]

in what regards? that it's not tensioning properly or that it's binding up? Is it common for the tensioner to fail?


almost sounds like its not enough tension on it. :hmm:



but what seems weird is that you say i stops after the car is warm.

[sheefo2k]

I had the same issue, went bough a step smaller belt and it fixed everything. silky smooth sno squeeks anymore and perfect.

[Kanaljen]

My belt was actually "jumping" around on the SC pulley. I created a very thin washer to put behind the pulley (since the pulley was obviously not perfectly allign with the other pulleys) and things went dead quiet.

But again, my belt jumped back and forth in the groves in the SC pulley, not sure if that is your problem.

Make sure the tensioner is not maxed out. If it is, by a smaller belt.

[Asbjorn@ESS]

Lafengas:

I recommend replacing the idler pulleys and tensioner as well as the drive belt. This is recommended maintenance every 25-30.000 miles.

Kanaljen:

The original E46 non-M ESS VT pulley is actually a offset original Vortech pulley, if somebody has replaced the pulley with a standard Vortech one in the mean time (since the E46 non-M VT1 kit has to be at least ~4yrs old by now) it will cause the belt to not align properly. The original pulley/bracket design is 100% straight and laser measured during R&D, but since these are all old 2nd hand kits now it is no telling what has been done to them anymore. It is also important that the bracket->alternator mount spacers are the correct ones for your kit, we delivered the VT1 kit with both 10 and later 12mm main SC brackets and if you ordered a new set of spacers for the wrong bracket the offset will be off. Check all of this.

[Asbjorn@ESS]

Cliff Notes below.

Last year in the fall, my drive belt started squeeking pretty bad and it was rythmatic. I would spray some silicon on it and it'd go away for a little while (10-15mis, sometims longer) then the squeek would come back.

Like i mentioned, it was rythmatic..not with engine RPM but with Belt RPM. I put the car in storage for the winter, figured i'd worry about it come spring.

I went to change the belt, and noticed my water pump pulley had excessive play in it, so i also changed my water pump. Put a new belt on and instead of squeeling, now it's jumping 1-2 ribs off my S/C drive pulley...rythmatically (at idle, aprox. once a second).

This only happens when the engine is cold, then it seems stops jumping.

I have the ESS VT2 supercharger and have the UUC underdrive pulleys and my belt length I replaced with is 85.5" (that seemed to work well with the tensioner)


CLIFFS:

1.) replaced rythmatically squeeky belt
2.) Found water pump going bad, changed that too
3.) Replaced drive belt with new
4.) Now my belt is jumping off the S/C drive pulley aprox 1-2 ribs
5.) no visible sign of pulleys being out of line


Any Ideas? Has anybody diagnosed a similar problem? S/C bracket warped or known to move?

would like some input before i start ripping everything apart.

We also do not recommend the use of underdrive pulleys with our kits. The belt loop is designed and tested with oem pulley sizes and the engine needs full coolant system capacity with the SC on.

[Kanaljen]

Yeah, my kit might have some additional peices added over time so that might have been the issue. In fact, I think the previous owner said something about replacing the pulley so you might be spot on. It was an easy fix though.. just took the pulley off, added a spacer and the belt never jumped again.


Lafengas:

I recommend replacing the idler pulleys and tensioner as well as the drive belt. This is recommended maintenance every 25-30.000 miles.

Kanaljen:

The original E46 non-M ESS VT pulley is actually a offset original Vortech pulley, if somebody has replaced the pulley with a standard Vortech one in the mean time (since the E46 non-M VT1 kit has to be at least ~4yrs old by now) it will cause the belt to not align properly. The original pulley/bracket design is 100% straight and laser measured during R&D, but since these are all old 2nd hand kits now it is no telling what has been done to them anymore. It is also important that the bracket->alternator mount spacers are the correct ones for your kit, we delivered the VT1 kit with both 10 and later 12mm main SC brackets and if you ordered a new set of spacers for the wrong bracket the offset will be off. Check all of this.