Hey folks,

The rear main seal on the GL was leaking pretty bad when we bought it and has gotten to the point where it's leaving puddles on the driveway now. Since I just happen to have a 550 engine sitting around I decided to fix it up and swap it in. It'll give me plenty of time to find parts and get everything screwed together. I'm replacing the timing chain and guides which meant pulling the heads off which meant getting them resurfaced. The good news is the machine shop said the valves and heads overall looked to be in great shape, and passed the compression test no problem. I've cleaned the carbon off the pistons and installed a new oil pump and pickup, but I'm otherwise leaving the bottom end alone. All of the rod bearings feel nice and tight and the cam bearings were in remarkably good shape so I think the engine was taken care of.

The big gray area is getting the engine in and out. I'm sure it can be done, but has anyone here done it and have any tips? I know the wiper cowl can be removed, and ultimately I'll remove as much off the front as I need to but naturally the less the better.

Also, any ideas on things to replace while I've got it apart?

 

Engine swaps on most Mercedes, 164 included is done by putting the car on a two post lift and dropping the entire front subframe.

 

I have heard of people doing it up and out. Of course, you have to take apart the front body section. I think it is more work but if the lift is not handy ...

 

My experience is with the OM642 not the, what? m273?, but up and out was pretty simple for mine. The hood goes up into the service position, remove all the inner engine compartment walls, pull the radiator and fan, set the AC compressor to the side, pop the bellhousing bolts, and up it goes. The biggest issue I had was that my engine crane was just barely too short of a reach so I had to fiddle around with the amount of lift on the front of the car to get the bumper to clear the hydraulic cylinder on the crane. Maybe the extra cylinders make that a lot harder. I don't know what it says for the gassers, but WIS calls for up-and-out for the turdbodiesel.