W124 230e What's This Rattling Noise??

[busters the boy!]

Hello chaps
Car has suddenly started to make this fierce racket on start-up. Only when cold. Was serviced last week and before that was running a bit lumpy due to fritzed distributor cap. That and spark plugs and leads replaced at service last week. Sounded normal after service, but about 4 days later starts like this:

http://www.youtube.com/watch?v=9GyfibSNuSU&feature=youtu.be



Oil pressure at 3 and no other issues I'm aware of. I'm worried in case it's either the timing chain (don't know what that sounds like) or the same as this guy - who needed a new engine. eek. Is it the same noise? I can't tell for panicking.

http://youtu.be/Mfpyqq9CQ7c

 

[kth286]

Check oil level first.

The timing chain tensioner uses a blend of oil pressure and spring load to keep the chain
from thrashing around at start up.

There is a one way oil valve in the block that should keep the oil within the tensioner.

 

[balge59]

Don't think you would still have full oil pressure if a big-end was gone?

Could try to localise the noise with a 'stethoscope' - long screwdriver or some-such.
Seem to recall you can see the timing chain via the oil cap, enough to try lifting it off the sprocket to check slackness?

Other thing that springs to mind, my 230TE shed one of it's heat-shields, which got trapped and made a real racket against the engine...

 

[busters the boy!]

Thanks both.

Oil level is fine.

Will check what you suggested balge59.

Also saw this comment left on another YouTube video of a noisy W124:

Try replacing the accessory belt tensioner damper strut, it worked for me. It connects from the belt tensioner to the thermostat housing and when it fails it sends vibrations to the thermostat housing causing that chattering sound. Next time you cold start, carefully hold the top end of the damper where it connects to the thermostat, you'll find the noise goes away

Hope it's something that simple, this car hasn't been anywhere near as trouble-free as my old 230e.

 

[grober]

Could be the polyV belt tensioner as mentioned. Or the timing chain tensioner or perhaps one of the timing chain guides has broken. HAS THE CAR GOT THE SINGLE OR DUPLEX TIMING CHAIN- you can check this by feel through the cam cover oil fill cap [ with the engine off obviously. Other thing might be a faulty /blocked hydraulic tappet. Has your garage used the right oil. An engine of that vintage won't take to a new thin synthetic- may flow out of the tappets more easily.

 

[Peter C1974]

Could be the polyV belt tensioner as mentioned. Or the timing chain tensioner or perhaps one of the timing chain guides has broken. HAS THE CAR GOT THE SINGLE OR DUPLEX TIMING CHAIN- you can check this by feel through the cam cover oil fill cap [ with the engine off obviously. Other thing might be a faulty /blocked hydraulic tappet. Has your garage used the right oil. An engine of that vintage won't take to a new thin synthetic- may flow out of the tappets more easily.

An '89 M102 should have a duplex chain. My '88 W124 230E had a duplex chain.

 

[busters the boy!]

Thanks both, only just seen these posts. Tbh, the poor old car has taken a back seat in the last couple of days due to chaos of xmas preparations. Back on the case tomorrow.

Grober, it's had synthetic oil in it since I've owned it. Merparts serviced it when I bought it and put Fuchs synthetic oil in and my local garage have just put some synth oil in it, but I don't know what brand they use (doubt it would be Fuchs though).

So it does sound like a timing chain then? eek!