Timing components

[NC325iC]

So, as many will know the timing chain tensioner guide is not currently available for the m42 case.

I am working on an m42 to swap into my '74 2002 and just found this out within the past few days so I'm kinda annoyed by this.

I Have a couple of questions

1) is it possible to convert the late m42 case to use the m44 tensioner guide?

I don't want to use the m44 case, don't wanna deal with the cps issue or get another oil pump.

2) does anyone have an m42 tensioner guide that is lightly worn that they would sell?

My engine has 200k miles on it and the guides show it. I don't need brand new ones just some with lighter wear. PM me if you've got something.

[roguetoaster]

I think I posted a comparative of the two arms and I think I remember that the only difference was hole diameter, with the M44 having a larger hole. So, if you could sleeve it you could run it, assuming we are talking the passenger side guide.

[NC325iC]

Yeah the passenger side rail that the tensioner pushes against. I will search for your post.

I have read that the newer one uses an m8 bolt at the bottom and the older an m6. Maybe drilling and tapping a larger hole would work.

I may end up changing my mind in the m44 case though. They are way cheaper on eBay than later m42

[gooseman]

Sent you PM

[cgk_iii]

I think I posted a comparative of the two arms and I think I remember that the only difference was hole diameter, with the M44 having a larger hole. So, if you could sleeve it you could run it, assuming we are talking the passenger side guide.

interested in this. I can’t seem to find the post you mention would you be able to provide a link?

[roguetoaster]

I have no info beyond those images, so I can't measure it, but visually it was the same except for the pivot bore.

[bmwman91]

Per RealOEM, the M42 guide sits on an 8mm dowel, and is held on with a circlip. The M44 guide has a larger hole since it is held with an 8mm bolt and some sort of sleeve that fits around the bolt body. Assuming they are the same thickness, you could possibly turn a reducer sleeve that would enable the M44 guide to run on the M42's dowel.

M42

https://www.realoem.com/bmw/enUS/showparts?id=AF93-USA-10-1990-E30-BMW-318is&diagId=11_4367

M44

https://www.realoem.com/bmw/enUS/showparts?id=BE73-USA-07-1997-E36-BMW-318is&diagId=11_6106

[NC325iC]

Without looking at the case I wonder if you could drill and tap the m42 case for the m44 bolt and sleeve setup. May already be the right threads?

[cgk_iii]

This should work. Im hitting the 200k mark on my m42. Its time to get these timing components taken care of.

I'm ordering tensioner rail
P/N:11311743262

https://www.realoem.com/bmw/enUS/part?id=AJ93-USA-10-1990-E30-BMW-318i&mg=11&sg=25&diagId=11_4367&q=11311743262

and m42 dowel/bolt
P/N: 11311721322

https://www.realoem.com/bmw/enUS/part?id=BK53-USA---E36-BMW-318i&mg=11&sg=25&diagId=11_1370&q=11311721322

Ill take some measurements and see what i can come up with and post back here. Should be here in a few days if pelican has everything in stock.

[bmwman91]

Without looking at the case I wonder if you could drill and tap the m42 case for the m44 bolt and sleeve setup. May already be the right threads?

If the 8mm dowel in the M42 also has M8 threads, then maybe the M44 stuff could swap right in without drilling. Worst case, the hole is too shallow and needs to be made deeper (or the M44 bolt needs to be "trimmed").

[bmwman91]

This should work. Im hitting the 200k mark on my m42. Its time to get these timing components taken care of.

I'm ordering tensioner rail
P/N:11311743262

https://www.realoem.com/bmw/enUS/part?id=AJ93-USA-10-1990-E30-BMW-318i&mg=11&sg=25&diagId=11_4367&q=11311743262

and m42 dowel/bolt
P/N: 11311721322

https://www.realoem.com/bmw/enUS/part?id=BK53-USA---E36-BMW-318i&mg=11&sg=25&diagId=11_1370&q=11311721322

Ill take some measurements and see what i can come up with and post back here. Should be here in a few days if pelican has everything in stock.

Cool, yeah can you get some good photos of the dowel and threads in the timing case? It'll be good to get concrete info out there for everyone since this is becoming a real issue for M42 owners!

[cgk_iii]

Cool, yeah can you get some good photos of the dowel and threads in the timing case? It'll be good to get concrete info out there for everyone since this is becoming a real issue for M42 owners!

No problem i will keep everyone posted! People often just upgrade to an m44 or swap out the case which IMO is way more work than turning a sleeve or a new dowel to make an m44 part work. Anyways, we will see when the parts arrive.

[TobyB]

Well, getting rid of that sprocket's worth the effort.

Do remember that the late M42's very similar to the M44 timing setup.

t

[bmwman91]

That stupid sprocket...it got me TWICE lol. First time the bearings blew out, which damaged the timing case and I did not notice, so about 16 months later the mounting boss it bolts to broke off entirely and that was the end of the motor lol.

[cgk_iii]

Just received the m42 bolt and m44 tensioner. The e30 bolt is indeed an M8 and is 50mm in length just like the M44 so in theory, the M44 rail should work just fine with the bushing (11311247452) and a M8 x 50 bolt (07119904533)