Need help with timing chain cover in M103

[Michael Pillay]

Hello,
I have a 1990 300SEL. I am trying to change the timing chain and guides but am having difficulty removing the timing chain cover. The cover itself is loose but the hub that the harmonic balancer fits on has a ring/sleeve that is preventing the cover from coming of. I have posted a picture of it below. I tried removing the sleeve with a three arm puller, but the arm on the puller snapped. If you could give me some information on removing the cover, I would really appreciate it.

Thanks,
Mike

[duxthe1]

That is a 27mm bolt in the front of the hub that is torqued around 250ft/lb. You'll have to remove that bolt then the hub.

[Michael Pillay]

I assume there is a tool of some kind to keep the entire thing from rotating....right??? If this tool does exist, any idea where I can get it?

[duxthe1]

There is a mercedes tool that locks the flywheel. Don't know the part# off the top of my head. In a pinch you can wedge something (think wood) into the flywheel from the bottom through the opening in oil pan but that does have it's risks and I assume no responsibility for your actions. Another alternative is to put some bolts into the hub and use a stout prybar between them to hold the crank, but that may have limited success, that crank bolt is TIGHT! ~250ft/lbs Maybe a combination of the two will get it out for you. Good luck!

[J.HIDALGO]

Since I did not have the tool, I ended up getting a big screwdriver into the flywheel (like it was suggested before) and praying that nothing would break. It worked and I did not break anything. A big breaker bar helped me loosen the bolt. You luck may be differnt than mine...Do a search and you should find an old post begging for suggestions...

[wbain5280]

See my reply over on Benzworld.

[pmizell]

I wedge a piece of wood up into the flywheel as suggested with no problems. Watch your knuckles and wrist when breaking that bolt loose! I think I stood on top of the breaker bar and used my foot to do the job

Good Luck

[Michael Pillay]

I will give it a try....I am a bit nervous about it though

I have a 1/2 impact gun I will see it it will fit in there. I have a new harmonic balancer on the way. The little sensor on the old one broke of. I will assume that that I should install the hb then take of the nut that way I can reset to TDC. Hopefully my logic is correct.

Thank you for all your help.

[Michael Pillay]

Update.

The breaker bar did not work for me. I used my impact gun that is rated at 350 ft lbs with no luck. Got a impact gun with a rating of 710 ft lbs. The bolt came out after 30 seconds.

[Lenny Lipscomb]

I changed out the timing chain on a 88 300 a while back so I am somewhat familar with what you are facing. In your picture it appears that you have not removed the harm. damper pulley retaining screw. If not, you need to block the crank shaft from turning at the fly wheel and remove this screw. The flange should come off with little force (it is not a tappered fit). The timing cain cover on the 88 did not have a gasket - required a an MB sealant.

[S-Class Guru]

Ha, reminds me of a time we removed a similar BMW crank bolt.
We wedged an 18 inch Craftsman breakover against the frame and hit the starter. The breakover bar bent 90 degrees!
We got some pretty interesting looks at Sears when we took it in for our free replacement.

DG