My engine rattle

[Sajk]

Chain tensioner (one on side of block) replaced. Vanos replaced. Can't figure out what it is. Runs v well. Cat cams, remap, m54 intake manifold 24lb injectors so you know what's been done to it. It's difficult to isolate and sounds like it's coming from vanos but it's not. Rather than just keep throwing parts at it i thought someone might have heard this kind of noise before. Its much quieter when it's cold which makes me think it's hydraulic but I guess it could be a cat rattle also. Help please if possible.

View: https://youtu.be/vu6m_co2CPM

 

[t-tony]

Sounds like a front pulley damper failing. Does it have a composite front pulley?

Tony.

 

[Sajk]

Thanks Tony. How would I tell. Will take a look on realoem.

 

[Sajk]

Am on the right page? One of these.

RealOEM.com - Online BMW Parts Catalog

BMW parts Z3 E36 Z3 2.8 Diagram Selection

www.realoem.com

 

[t-tony]

Belt drive vibration damper. So yes it does have damper. You will need to remove the drive belts then inspect the pulley to see if the rubber component is split. Hope you find it is as it would be a simple fix.

Tony.

 

[Sajk]

Thanks Tony. What is the risk in driving it if that is the issue? I would guess it could fail completely and drop the belt?

Mine comes up with this part. This is the best pic I could find quickly.

Andrew

BMW M52TU Engine Crank AC Pulley Vibration Damper 1999-2002 E36 E46 E39 Z3 OEM | eBay

Find many great new & used options and get the best deals for BMW M52TU Engine Crank AC Pulley Vibration Damper 1999-2002 E36 E46 E39 Z3 OEM at the best online prices at eBay! Free shipping for many products!

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[t-tony]

If it did come apart it could throw the drive belts off, shatter the cooling fan blade and take out the radiator. So possibly a lot of damage, IF it is the damper. Really does sound like it to me.

Tony.

 

[Sajk]

Ok thanks. It sat for quite a few years and amazingly I did not lose many rubber components but maybe this one I did. Make sense why it is louder on the overrun if it's this. I guess louder when hot also as the rubber softens. Radiator out job?

 

[Sajk]

So Tony so I am clear this is actually the crank pulley Yes?

 

[t-tony]

Yes. The only other possibility to produce that type of noise is the dual mass flywheel absolutely shot.

Tony.

 

[IainP]

If you look from above with the engine running you can often see the runout on the pulley, that usually confirms it.

 

[NZ00Z3]

Have you checked the viscous clutch on the mechanical fan?

 

[Sajk]

@IainP
I can't really see the crank pulley from above as the fan is in the way. Will try to look at it from below.

@NZ00Z3
It is definitely working. I will try to reproduce the rattle when it's locked up.

 

[NZ00Z3]

It is definitely working. I will try to reproduce the rattle when it's locked up.

Maybe remove it and see if the noise goes away. It could be the precursor to blades falling off etc.

Large screw driver/pry bar and a 32mm spanner. Left hand thread.

 

[Sajk]

Will take a look on the weekend thanks

 

[Sajk]

Bad news. Had the car on the ramps and went over it with a stethoscope. Noise definitely from the top end. I think exhaust cam side. Everything else is quiet. ii's hard to tell at the top but i am pretty sure its the exhaust cam side of the head.

 

[Mike Fishwick]

If you have air con, have you checked the bearing in the belt tensioner?

 

[Sajk]

Hi Mike, 99.9% sure it's in the top end. When i am undervtye car it's quiet down there. Having done more reading pretty sure its the bigger cams causing lateral movement in the vanos piston new vanos or not.

We pulling off the valve cover Monday to make sure nothing horrible is going on under there. I suspect a rattle kit is needed. Should have gone there first b4 replacing the vanos. Time will tell.