Rover 75 / BMW 118d/120d/318d/320d/520d Engine Clatter

Owen

The 75's diesel engine has been very very very noisy over the last 2 weeks. I'd a rattle coming from under the bonnet which sounded like someone banging with a hammer very quickly. I initially thought it might be the timing chain clattering, but it wasn't.

I switched the aircon on and off, and it seemed to remove the rattle altogether - so I surmised that the aircon clutch on the pump must be screwed. Went shopping for a pump as clutch kits weren't available. In the mean time, I cut the aircon belt off to stop it rattling as it had started to creep in when the aircon was turned off too. And then, Murphy's law, the rattle got really bad.

Turns out it was the crankshaft pulley which has 2 belt take offs on it, one for the serpentine, and one for the aircon. I'm guessing having the aircon one on was keeping it more in balance, and when I took it off there was one plane of tension.

Long and the short of it is that I'm carless until the new pulley arrives tomorrow. So if you get a rattle in the cars in the subject line, check the crankshaft pulley too. Also, check the prices around. Some places were 320 Euro, some were 170. Delivered to the door from Europarts it's coming to 74 Sterling.

Owen

Boy that was a horrible job. This is what a disintegrated crankshaft pulley looks like inside, I'd say it'd have lasted another few minutes, no more. The rubber which should join the inner to the outer pulley had all but separated, and there was rubber debris all over the engine casing.

Getting this off should require a special tool, but you can insert a prybar into the torque convertor and lock up the crank. It's held on with ridiculous force, I mean off the wall force. It took 2 of us to open the bolt. The auto tensioning pulley for the accessory belt is a 24 socket btw too for anyone wanting to loosen that off - which you have to do.

She's ticking away like a little mouses heart now again.

richardsheil

Well done. And thanks for letting people know.

Slidey

You have to wonder what was wrong with a solid crank pulley and alternator pulley for that matter.

Good on ya for putting it up, hopefully will help someone.

Plug

Slidey wrote: »

You have to wonder what was wrong with a solid crank pulley and alternator pulley for that matter.

Good on ya for putting it up, hopefully will help someone.

Thats what I wonder, it must be for vibration or something when the belt is under strain. The new transit has them and i've seen a few go.

El Guapo!

Fair play for letting people know.

Its a common enough problem. The rubber part is to stop torsional vibration. I've replaced them on 3series BMW's, and a couple of E-class Mercs.
Also a friend of mine had a B-class merc come into his job with the same problem and when he went to replace it it was a nightmare to get off so he rang Mercedes for some tips on how to remove it and apparently its an engine-out job!! :eek:

SilverBell

A similar thing used to happen the dual mass flywheels on Toyotas, the rubber bit went in the middle. Happened on Land Cruisers with the HZJ engine.

mickdw

A bit of free advertising there paintdoctor:D