W123 OM648 Project - Page 3 - PeachParts Mercedes-Benz Forum

BirthdayBenz · #1 02-07-2022, 10:25 AM

I’ve begun an ambitious project which I hope to finish. I see two possible outcomes. The first is having a pretty unique, quick, and fun to drive W123 and the second is learning why I’ve only see one other car with this swap.

Why not an OM606?
Engines are very costly and rare then have unknown miles ($3k or so)
Mechanical injection pumps are also costly ($2-3k)

I’m early in this project and am aware of the following challenges I’ll need to overcome in regards to the swap. I’m sure I’ll find others.

1. Engine mounts
2. Transmission/mount/shifter
3. Electronics (ecu/CAN,etc)
4. Vacuum pump (OM648 has no vacuum)
5. Fuel pump (OM648 requires electric pump before mechanical)
6. Cooling
7. Intercooler

Engine Mounts. I’m sure I can fab something up. I’ve got a bunch of mounts around. Some from an SL some from the W123, Some from G500, Some out of the CDI.

Transmission. My W123 has a 4speed manual. I wont be using that. Even if an adapter was fabricated I’m sure it would explode eating over four times the HP and torque the little 240D left the factory with. I wont be running an automatic.

What plan to run is a six speed GS6-37DZ transmission from a diesel 1 Series BMW.

I think it fits in the transmission tunnel of the W123. I'll need to have an engine mounted to it before I can be sure on the positioning

How does a BMW six speed transmission connect to an OM648? Dieselpump UK.

Electronics. This is a probably the issue which prevents this swap from taking place. I've seen the OM648 swapped into Land Rover Defenders and boats in Europe so it must be possible. I've purchased a harness from an OM613 and a stand alone ECU from Blacksmoke Racing.

I have a complete donor car from a Copart auction which was less expensive than any OM606 I've seen for sale. It runs and drives great. I almost have the OM648 ready to come out.