603 Front crank seal questions

[pilot53]

1.) Is it possible to pull the hub and vibration dampener out together without pulling the dampener off of the hub?

2.) If not, can the dowel pin be reused?

3.) What is the easiest way to stop the crank from rotating when torquing the nut to 230 ft lbs?

[g300d]

When we were looking for why the damper was wobbling on my 1990 300D we pulled the damper/pulley from the hub first, then removed the crankshaft bolt on the nose of the crankshaft so we could remove the hub. The damper only fits on the hub one way by the bolt pattern it has.

I dont know about MB guidelines for this but we re-used the dowel pin.

I hadnt seen how they torqued it but when I was reseaching it I saw references to holding it from the trans side.

Oh and the wobble was caused by the hub. Nothing was obviously wrong with it but when we swapped it out with one from another car the wobble disappeared.

Am thankful it was that, was half expecting to see a messed up crank nose when we were opening it up to check.

[Usaguy]

Originally Posted by pilot53

1.) Is it possible to pull the hub and vibration dampener out together without pulling the dampener off of the hub?

its easier to remove them together than to try to separate them. You will need a crank puller.

Allen bolts holding them together and where you screw in the puller can give you trouble

Originally Posted by pilot53

2.) If not, can the dowel pin be reused?

OM603 doesn't use dowel pins its using a crank key and it doesn't need renewing

Set the crank a tdc when removing the balancer because then the key will be facing up

Originally Posted by pilot53

3.) What is the easiest way to stop the crank from rotating when torquing the nut to 230 ft lbs?

a $30 flywheel lock:

https://www.ebay.com/itm/Mercedes-Benz-Flywheel-Locking-Tool/254474821735?hash=item3b3fe1a067:g:mpoAAOSwkNZUfPvV

[pilot53]

Ok so I got the vibration damper off easy peasy with a puller kit and the flywheel lock tool but Im having major issues with the woodruff key.

I can't for the life of me get the key to stay in place when installing the hub, why is this so hard???!! I ended up barely getting the hub on the crank without moving the key but it must have moved as I tightened the hub down because it got real tight and when I took it apart the key was sheared.

[Usaguy]

Originally Posted by pilot53

Ok so I got the vibration damper off easy peasy with a puller kit and the flywheel lock tool but Im having major issues with the woodruff key.

I can't for the life of me get the key to stay in place when installing the hub, why is this so hard???!! I ended up barely getting the hub on the crank without moving the key but it must have moved as I tightened the hub down because it got real tight and when I took it apart the key was sheared.

Can't find it in the manual for the OM603 but on the M103 (almost the same dampener setup) you have to heat up the balancer to 50C (120F) and then install it. Last time I did mine this way I didn't have any problems.


If you post the model and year of your car/engine I will look up the part number of the key for you (In case they are different between models)

[pilot53]

Originally Posted by christuna

Can't find it in the manual for the OM603 but on the M103 (almost the same dampener setup) you have to heat up the balancer to 50C (120F) and then install it. Last time I did mine this way I didn't have any problems.


If you post the model and year of your car/engine I will look up the part number of the key for you (In case they are different between models)

oh wow ok, I had no idea you needed to heat this up since it came off pretty easy, and slides on easy without the key. I will give that a try next time, as well as installing it with the vibration damper removed for more access. Its a 1986 300sdl, I found this p/n: 1089910067 does that seem right? I can't find anything else online about it.

[Usaguy]

Originally Posted by pilot53

oh wow ok, I had no idea you needed to heat this up since it came off pretty easy, and slides on easy without the key. I will give that a try next time, as well as installing it with the vibration damper removed for more access. Its a 1986 300sdl

It's safer to heat up the hub when it's removed from the balancer since you're not running the risk of damaging the rubber

Originally Posted by pilot53

I found this p/n: 1089910067 does that seem right?

yes