Timing chain guides

[Marcp]

My 1991 318is makes a almost diesel like rattle at about 3000rpms, is this the guides worn out?   I have replaced the tensioner but didnt make any difference, is it something I can do at home?   I have loads of decent tools, never worked with timing chains before though, only belts.

Is changing the sprockets really needed?   I'll whip the cam cover off tomorrow, and take a picture of the cam sprocket teeth.   Im mostly worried about pulling the bottom vibration dampner off and getting the fan off tbh.

Any hints and tips on shortcuts and what to look out for?

Thanks!!

[rhogg]

Lots of threads on this.  Best DIY is Brendan Purcells :

http://www.esatclear.ie/~bpurcell/318istimingchain.html

You are more likley to need to change the sprokets than the guides.  Assembly is straight forward just paying attention to the cam alignment. I did not use the cam holding tool just the straight rule and a drill bit for the TDC flywheel alignment

[swiss318is]

...well, the chain and stuff around them produces more a ratteling noise... but old hydros convert the engine into a diesel... (new around 600.-$)

[Marcp]

Testicals... Changed loads of cambelts, no worries.   How is the M42 to work on at home?   Was hoping not to need to change the cam sprockets purely beacuse of costs, but after removing the cam cover last night the sprockets are pointy, which was a pleasent end to the day

Thanks guys.

[peerless]

Cam sprockets are only about $40 each. And make sure you change the chain guide rail. The old style is stamped metal with rubber liner. The chain starts slapping around, the metal fatigues and breaks apart. The chunks of chain guide drop to the crank gear and wrap in between the sprocket and chain, slipping the timing and bending valves.

[Ernest]

That mess in the above post is mine.  Change all your timing components if you enjoy driving your car.