OM61x crankshaft spacer ring puller
 

I'm slowly prepping an OM616.916 to go into my 1960 W121. With the engine on a stand, upside down with the oil pan off, I haven't been able to get the oil seal spacer ring on the crank to move even a little. I know there's a special tool for that purpose, but it's expensive. I looked in the tool rental thread and didnt see it in the list. Anybody have one? Even better, anyone in the Denver area have one?

I suppose I could try to remove it destructively, but to do that without damaging the crank seems like it could be a long, tedious process.

May be able to split it w/ a cold chisel- be careful not to damage the shaft. Once it splits there will be no tension, should slide right off.

I heated a flat screwdriver orange, bent the last 3/8" about 90-100 degrees in a vise and then tempered it (dark cherry, oil quench). This let me pry it off the first 1/8".

Had a puller made by a friend in a sheet metal shop, got it off the rest of the way.

I can mail it if you like, or sketch it out if you have a friend too. I'm in buffalo NY.

I had the same trouble on my OM617 - the spacer ring was well and truly stuck on the crankshaft.

With the upper oil pan off I drilled carefully into the ring so that there was enough of an impression / blind hole so that I could use a parallel pin punch to knock it round and off of the crankshaft. This was done radially onto the surface of the spacer on the crankshaft - so in a direction following the centre line of a cylinder down towards the crank.

On other engines, there is a section above the crank held on by a number of bolts/screws. Remove that and you'll gain access to the spacer ring. Heat said ring and pull off. Two people make this easier.

The above procedure I've seen on video, haven't done it.

I did it this way as a 1 man job with the engine upright, it didn't require any heat.

That would harden it.

If someone else tries what you did; depending on the Steel the Tool is made from it could become too hard and when the Tool is used Break off.

Tempering comes after the hardening when the cooled off Tool is raised up a lower temp to soften it up a little so it does not break.

Also a lot of Tools use Air Hardening Steel and quenching them in Oil would not harden them properly.

For several years back in the 1980s I made Knives as a hobby; I stll have the Electric Heat Treating Furnace and other Equipment I used.

You can actually use a regular over to Temper; heating the hardened tool slowly bacu up to around 350-425 degrees F is enough to soften the Tool an little and toughen it up. Better if you can hang the item you want to temper vertically.

Cool, no pun intended...

Thanks for all the responses. I'll give it another shot, hopefully I'll have time tonight. I think first I'll find something more appropriate than a plastic-handled screwdriver to hammer on and see if I can get it to budge. I've got a couple of gear pullers if I can pry it out part way. If that doesn't work I'll try the other ideas mentioned.

I got it off tonight. Just took some patience and some more appropriate tools. I started with a couple of chisels to get it to move a little. Then used a variety of tools to pry and pull and eventually got it free.

Thanks for the tips and advice. I was thinking of giving up and had been considering not replacing it if I couldn't get it off, even though I could see and feel some grooves worn in it. Now this motor should be leak free when I get it in the car.

I can only get it to rotate with a cold chisel. The chisel tip gets dented quite easily. I think the spacer metal is harder (stainless?) than the chisel itself. I pounded on it both hard and soft for 10 minutes and it made a definite impression but didn't seem like it was making much progress after a while.

All the pulley pullers I could find SEEMED like they'd work but the one I found for rent just slid right off. If anything is going to pull it off, it needs to be on REALLY tight and around the whole thing, not just two or four points of grip.

Cobalt drill bits made a tiny dent in the front but would not go in past a point (ie the surface plating).

I can get it to slowly rotate, but I can't for the life of me get enough of a gap in the rear to place anything (not even a tiny L-shaped pick) behind it.

I am at a loss and the only thing I can think of is to use an arc welder to weld two metal rods to each side. Maybe some beat up screwdrivers or something else I don't mind sacrificing. They can be replaced more cheaply than getting a bunch of extra tools.

I'm hesitant to use a propane torch at all because, well, there's a bunch of oil/grease everywhere on the thing! But if the welding thing doesn't work, then I'll try that. Just with a bucket of water, my welding gloves, welding jacket, etc on.

I have always been able to slide spacers off by prying with two straight screwdrivers on opposite sides (ie: 180 degrees apart), simultaneously. The key is bringing it off evenly.

toomany_MBZ has it right.... There is a metal "arch" cover surrounding the spacer/seal area, and this arch/cover is preventing one from attacking the rear of the spacer straight on. There are 3 bolts on top and two female allen bolts on the side, from below, and then this plate just comes right off, giving straight access to the rear of the spacer from above.

I don't think brute force is even necessary.

Unfortunately, there is one allen bolt that doesn't have enough clearance for a ratchet, so I have to go to WalMart and see if they have a set of L-shaped allen wrenches. And after I just threw a set out because I thought they were useless.

http://i.ebayimg.com/t/1984-Mercedes...d5g~~60_12.JPG

This is what it looks like. If you see this above the spacer ring, take it off. Makes it all easier.

Right now it's 10pm but I got this off (using some allen wrenches for the underside bolts) and was able to use a cold chisel to rotate the ring a bit, which opened a tiny gap on the top left side, where I then used a small screw driver and my ballpeen hammer to wedge through. That then pushed the seal off a bit. I still have a ways to go, but from here it's a bit more realistic. Without the 90 degree angle of attack, I would not have been able to do this. Even compared to bending some screwdriver tips, it's still easier to have the extra room.

So far I'm just using gradually larger and larger things to hit with the hammer on the backside of the spacer, to wedge it forward. It's on way too tight for screwdrivers to work, and I'm wanting to avoid a propane torch given that there is oil everywhere.

Any pictures?

My SD needs a new front main seal

New seal installed:
http://img849.imageshack.us/img849/2209/newmainseal.jpg