PeachParts Mercedes-Benz Forum - View Single Post

bkc · #9 07-24-2014, 05:38 PM

Quote:

Originally Posted by winmutt

Why? You should be able to do this with all stock parts.

With the shorter motor, the tranny will be further forward as well, so the driveshaft needs to be longer. The mounts don't quite fit (almost). And the motor is slightly too tall with the crossmember as it is now. Moving the motor back to "normal" would hit the steering linkage stuff and require removing the crossmember and building entirely new mount points.

Quote:

Originally Posted by winmutt

Why wouldnt you keep the 602 eng and trans together? You will need to swap EDS over.

I am hoping to be able to take advantage of the 5th gear in the 722.500 in the r129. Plus it is electronic speedo and various other connections which should just work by keeping the existing tranny. At least that was my thinking. I still have the 722.418 tranny in case I end up needing to go with it instead.

Already have the EDS wiring 99% figured out. (Well, subject to finding problems once it is all together.) The 1% is getting info to the r129 systems that want data, such as the HGS/TCM and tach. That and I misplaced the actual EDS unit (I put it "somewhere safe") - need to keep tearing through the house and garage to find it...

Quote:

Originally Posted by winmutt

Of course the ratios will be off some but shouldnt matter.

Good to know. Which ratios? The rear diff is currently a 3.70, but if it proves problematic I can just swap in the 2.65 diff from any other r129 model (direct fit).

Quote:

Originally Posted by winmutt

Why arent you using m103 mounts?

I tried both the om602/w124 mounts and the m104/r129 mounts. The m104 mounts *almost* work, but the angle is off. I'm going to experiment more with the m104 mount arms, but I don't think that solves the problem. Since we have to modify the crossmember with the mount seats anyway, might as well just alter those at the same time. I don't have access to m103 mounts without buying a new set (and they should be pretty similar to the m104, anyway, I expect?).

Quote:

Originally Posted by winmutt

Can you not use the 124 ignition?

No, it is a w140/r129 style ignition switch. On the plus side, it should have the pinout for a 300/350SD, but that seems to use power to keep the engine on (hard to tell from the diagrams). May just go with that method for starters and worry about it later.

Quote:

Originally Posted by winmutt

This is not the first 129 swap. Google around and find ppl with good experience.

Yup, have seen a few, but not this particular swap so far. There's the om605 NA in the UK, and a 617 somewhere (lost that link), and the 602 into a few other models, but I've not seen om602/r129 (there was one that popped up on Craigslist briefly near Phoenix, but the ad expired before I got a chance to follow up with it).

Thanks!
-Bruce