Timing chain rattle?

[downforce22]

great photos. I may have to pull my car's engine at some point and do not often see the insides of the m42 timing case. Did you replace any of the lower gears?

[ThatOneEuroE30]

Crazy. When you have the deflector sprocket off, give the casting a very close inspection where it bolts on (all the ribs and such). I had a mysterious rattle at ~3000RPM that I could not figure out, and then the casting broke, so I suspect that there was a fracture down there or something which was vibrating.

I did not notice anything when i looked at it but tomorrow will pop the new back off and see if there is anything wrong with the casting for the deflector sprocket.

[bmwman91]

Crazy. When you have the deflector sprocket off, give the casting a very close inspection where it bolts on (all the ribs and such). I had a mysterious rattle at ~3000RPM that I could not figure out, and then the casting broke, so I suspect that there was a fracture down there or something which was vibrating.

[ThatOneEuroE30]

So tear down has begun and i got the new guides and what not on but the E clip went flying so i gotta grab one from my buddy tomorrow to finish it up. It honestly didn't look horrible when i took it apart and I would be lying if I said I'm not concerned. There is nothing that indicates a metal on metal situation like I have been hearing at 1900rpm. However the guides are worn and trash.











Hopefully this fixes the issue. Wish me luck! Will post more pics tomorrow of new components on. It was dark by the time I got them on.

[ThatOneEuroE30]

Cool. Good work keeping another M42 in good running condition! They are getting harder and harder to find anymore. They will never be S14-rare, but they are unique and neat engines within the E30 realm.

I personally love it and mines in a slick top so its that much better for me. They are getting incredibly hard to find especially around my neck of the woods. I need to find another one to have around to rebuild. I like have spare engines

[bmwman91]

Cool. Good work keeping another M42 in good running condition! They are getting harder and harder to find anymore. They will never be S14-rare, but they are unique and neat engines within the E30 realm.

[ThatOneEuroE30]

Makes sense. Most likely, it will be fine after a nice full overhaul. The sprocket failure is increasingly common, but it is probably a small percentage of M42's that experience it overall, and probably mostly the ones that had severely neglected timing assemblies (the PO of mine really let it go to hell).

Yea and I'm doing everything short of a full engine rebuild new cooling system etc. Person who worked on it last at what ever shop the PO took it to managed to over tighten the top rad hose and actually break the neck on it but it never leaked a drop I pulled the top hose and found that wonderful surprise on a rad i thought was still good. Car has 160k on it and I don't drive to much I bet in 5 years It still wont have hit 200k.

[bmwman91]

Makes sense. Most likely, it will be fine after a nice full overhaul. The sprocket failure is increasingly common, but it is probably a small percentage of M42's that experience it overall, and probably mostly the ones that had severely neglected timing assemblies (the PO of mine really let it go to hell).

[ThatOneEuroE30]

If you are going to go to the trouble of breaking open the timing case, I HIGHLY recommend changing to a 1994+ M42 timing case. That (EXPENSIVE) deflector sprocket is a time bomb because either it will break, or the timing case casting that it bolts to will fail. Ask me how I know...

For the most part, the later M42 timing case is a straight bolt-in. You just need to make sure to get the proper gasket that goes between it and the block (see RealOEM). Also, the little guide that it uses instead of the deflector sprocket is way cheaper. Maybe you can return the new sprocket you bought?

I'm just gonna keep it how it is and put all new shit in. I dont have time to return everything and wait for other stuff to ship. This is my daily driver and my truck is costing me 100 bucks a week in diesel while this is down and its been down for 3 weeks. Its killing me.

[bmwman91]

If you are going to go to the trouble of breaking open the timing case, I HIGHLY recommend changing to a 1994+ M42 timing case. That (EXPENSIVE) deflector sprocket is a time bomb because either it will break, or the timing case casting that it bolts to will fail. Ask me how I know...

For the most part, the later M42 timing case is a straight bolt-in. You just need to make sure to get the proper gasket that goes between it and the block (see RealOEM). Also, the little guide that it uses instead of the deflector sprocket is way cheaper. Maybe you can return the new sprocket you bought?

[ThatOneEuroE30]

It also got the $250 slider that makes me go, hmmmm mm m M54....

t

No 24v for me lol. I made this pic for a buddy who told me to go s52. But just imagine its and m54 too

[roguetoaster]

I think you mean later timing case- didn't the pre- 94
E36 also get the idler system?

It also got the $250 slider that makes me go, hmmmm mm m M54....

t

Yeah, there's a changeover date and an somewhat reliable way to distinguish the two M42s, but I can't recall what that is right now.

[TobyB]

early E36 M42 timing case

I think you mean later M42 timing case- didn't the pre- 94
E36 also get the idler system?

It also got the $250 slider that makes me go, hmmmm mm m M54....

t

[ThatOneEuroE30]

PN: 11311727569
Reference: http://bmwfans.info/parts-catalog/E3...in/#1727569_11

I had fcp add this to my order since it appears there is a bearing in the center. Im sure its rather crunchy.

[ThatOneEuroE30]

This is where an inspection scope comes in very handy. I've been happy with the fairly cheap Aardvark scope I got a few years ago.

I look forward to your tear down/inspection results.

Will likely do it tomorrow. It's supposed to be rain free and nice out so I should be fine taking it apart to inspect while waiting for parts to arrive. I have seriously bee contemplating picking one up and just getting a nice one since once i graduate school it will get used a lot.