109 replies to this topic

[MrSimba]

If you've got one installed, change it back to OE

[The Batman]

You think this is the problem?

[Bumblebee]

Why is this Simon?

[techieboy]

Wouldn't surprise me. I've always been dubious of them, especially if the engine see's high rpm's.

[MrSimba]

Yep, the OE pulley is damped taking the harmonic's from the crank, the alloy underdrive pulleys are not and the un-damped stresses would appear to have been transmitted to the trigger wheel bolts that then sheared & took the engine with it! Anyone with one installed would be well advised to re fit the OE pulley

Edited by MrSimba, 24 March 2013 - 10:01 PM.

[TheHood]

My guess would be because of the fact they don't call them harmonic balancers for the fun of it..... ETA too late

Edited by TheHood, 24 March 2013 - 10:01 PM.

[Bumblebee]

Even though I'm at stage 4? Or does this not make a difference?

[techieboy]

Sorry you had to be the one to find that out Simon. Pretty sure we've argued the merits before and even Mr Randall advised against them as well.

[MrSimba]

Nev has contacted another owner who had trigger wheel bolts shear... They also had an alloy pulley fitted

Edited by MrSimba, 24 March 2013 - 10:06 PM.

[Bumblebee]

I best be on the phone to Liam

[The Batman]

On the z22/lsj the trigger wheels aren't bolted on... Never heard of it happen to one of our engines either..

[Darcini]

Ollie at Phoenix has the same opinion of them.

[MrSimba]

Easy job to change, but looking the very likely cause of my engine failure, mine was a TTV but its not the make that's important it's the fact they are un-damped. My engine was revved to 7400rpm on the dyno when it failed maybe at lower rpm they are fine, but sure my engine would still be fine if I'd had an OE pulley fitted.

[Graeme Lambert]

Easy job to change, but looking the very likely cause of my engine failure, mine was a TTV but its not the make that's important it's the fact they are un-damped.

My engine was revved to 7400rpm on the dyno when it failed maybe at lower rpm they are fine, but sure my engine would still be fine if I'd had an OE pulley fitted.

Not good news. Currently have an MMG underdrive kit installed. Be interesting to see what Liam/DG has to say about all of this...

In the meantime, anyone know the best place to get a new OEM one from - not sure if I kept my old one or not?

[VXT Tim]

Cheers for this info Si.

[MrSimba]

Well before everyone jumps on Liam & DG consider my engine failed at 7400rpm and producing over 400bhp so not exactly std! Lower power levels might be fine, I don't know, but in my case the alloy pulley is looking like the culprit.

[JohnTurbo]

Plus if you have one you need to get your magpie instinct checked out by a hypnotherapist.

[Graeme Lambert]

Plus if you have one you need to get your magpie instinct checked out by a hypnotherapist.

Or stop listening to DG?

G

[vocky]

On the z22/lsj the trigger wheels aren't bolted on... Never heard of it happen to one of our engines either..

the z22se/LSJ/L61 crank pulley is one piece and I've not heard of any problems either.

I know the z20let engines have a two piece crank pulley, so perhaps it's something to do with that set up

[Whiteboy]

I still have a full oe pulley, including the aircon delete idler, if anybody wants to buy it off me. The only thing missing is the drive belt. Steve