Timing case refresh done; Timing chain noise after warm up

[evbrad2002]

As posted on a separate thread, I refreshed my timing case with new chain, tensioner, sprockets, guides...also dropped pan and clear out all debris in the pickup and secured loose pan bolts (all done less than 1500 miles ago). Recently, while checking on another issue, I noticed timing case noise at idle after having driven the car.  The noise is not present at idle after cold start, even after letting it idle for some time, only after driving it a while.  The car runs great.  I went ahead and changed the oil for good measure and saw no evidence of any debris in the oil.

The fact that it does it after warm up and not cold has me stumped.  I know these engines tend to be noisy; can slight chain noise be "within normal limits" on these cars? Any suggestions?

[bmwman91]

This is only at idle? No noise at other RPMs when it is warmed up?

Is it almost a "rocks in a coffee can" type sound? When the noise occurs, try pressing the clutch pedal in. If it goes away, then it is probably just typical "Getrag rattle". The G240 is pretty notorious for having a sloppy input shaft and it can rattle a lot with the clutch pedal up at idle, mostly after the tranny fluid warms up & thins out.

[evbrad2002]

This is only at idle? No noise at other RPMs when it is warmed up?

Is it almost a "rocks in a coffee can" type sound? When the noise occurs, try pressing the clutch pedal in. If it goes away, then it is probably just typical "Getrag rattle". The G240 is pretty notorious for having a sloppy input shaft and it can rattle a lot with the clutch pedal up at idle, mostly after the tranny fluid warms up & thins out.

Good thought, and the car does have a light flywheel so there is quite a bit of chatter when clutch pedal is not depressed; but I'm afraid the noise is present even with the clutch pedal depressed...definitely from the timing case.  If I recall correctly, I believe I read one of your previous posts in which you had the adjusting screw on the driver's side chain guide back out or strip after replacement.  I'm wondering if something like this has occurred, though it still doesn't make since to me that the noise wouldn't be present at cold idle.  As to whether the noise is present at other RPMs, I can't hear it in the car as it's not super loud and didn't think to blip the throttle from under the hood to test this as I was so sure it was from the timing case.  An additional issue I noticed is that there is a slight wobble at the crank that seems to have developed. I don't recall it being present when I put everything back together initially...this could be damper/balancer wear I suppose.

[bmwman91]

Hmm. Well it is easy enough to check the top guide bolt since you only need to pull the valve cover to get a look at it. Thinking back, I may have had similar behavior leading up to the incident where the stupid idler sprocket snapped off its mount boss from the timing case. I don't want to make you worry any more or anything though, and if you just did a timing job it is probably OK. A year before my big failure, the original idler sprocket blew out its ball bearings which I suspect damaged the timing case but I didn't notice. So you are probably OK.

It is too bad that the stupid crank damper bolt is such a pain...it would be pretty easy to pull the timing covers without it!