Installing an OM603 engine in a gasser w124 - PeachParts Mercedes-Benz Forum

JordaanDMC-12 · #1 01-11-2010, 01:31 AM

Hey all again,

I just thought, since I love diesel so much and as I write this I predict all the responses that will just say: "just buy the actual w124 diesel model" lol But is it possible to fit a om603 engine in a normal 300E? I imagine you need to swap out suspension and swap out the transmission too? Will it fit or does the engine bay need some modifications as well? Driveshaft too?

Just curious....

junqueyardjim · #2 01-11-2010, 01:22 PM

But I am sure the 603 will fit in there like it was built for it, (and it was). Maybe the front springs are a bit more HD, because it would be heavier and the intake manifold system is a bit different then the M103, but that system has a lot of plastic in it which the M103 does not, which would lessen the weight differential. There are many small changes that would have to be made though, and they have to be done right, like the ignition switch, wiring, computer and changes in the fuel lines.

JordaanDMC-12 · #3 01-11-2010, 08:33 PM

Quote:

Originally Posted by junqueyardjim

But I am sure the 603 will fit in there like it was built for it, (and it was). Maybe the front springs are a bit more HD, because it would be heavier and the intake manifold system is a bit different then the M103, but that system has a lot of plastic in it which the M103 does not, which would lessen the weight differential. There are many small changes that would have to be made though, and they have to be done right, like the ignition switch, wiring, computer and changes in the fuel lines.

Hmmm yeah I think it might be pretty possible, it's like you said, it was meant for that same body. I might look into it one day if my current m103 engine fails me. I love the 87's and it'd be nice to pop it in the engine bay of an already familiar 300E or I guess D after the engine swap lol

Mike@Exclusive · #4 01-12-2010, 10:34 PM

a 124 came with a 603. It was called a 300D. not to be confused with the 300D 2.5 turbo.

wbain5280 · #5 01-12-2010, 11:08 PM

Yes you can but you will run into problems with emission inspection. Check with the Calif DMV for guidance.

JordaanDMC-12 · #6 01-15-2010, 01:44 AM

Thanks for the replies, I think if I have enough money one day and my m103 dies on me, I might do this.

Jeremy5848 · #7 01-15-2010, 12:55 PM

It should be do-able, especially if you have a 1987 300D Turbo (W124, OM603) donor car to get all of the bits and pieces that you will need. Otherwise you will have to scrounge forever or buy new from the factory; neither is pretty.

It's also possible to get a 603 engine from a 1986-87 300SDL (W126). It will be labeled "603.970," I believe, while the '87 300D (W124) has a 603.960 engine. There will be fewer parts that will cross over to the 124 chassis but at least the engine will be almost identical. (I've never seen a list of differences.)

Should you run across a "loose" 603 engine, try to get it bench tested to confirm that it actually runs and has good compression and all that before buying. Rebuilding a 603 engine is expensive: Metric Motors charges $8000+ for their rebuilt OM603s.

As already mentioned, California DMV usually looks at cars smog-wise based upon how they were originally built. There may be an "exception" procedure that you will have to discover. Should you ever do this project, please publish how you were able to change the car from "gasser, bi-annual smog check required" to "diesel, exempt."

Jeremy

scottmcphee · #8 01-15-2010, 05:17 PM

Careful which pump you pull up to when refueling. Get a D on trunk deck and get the diesel fuel only sticker at the filler lid... Then you should be good to put a 603 in there.

Got one in mine!

JordaanDMC-12 · #9 01-15-2010, 11:21 PM

Quote:

Originally Posted by Jeremy5848

It should be do-able, especially if you have a 1987 300D Turbo (W124, OM603) donor car to get all of the bits and pieces that you will need. Otherwise you will have to scrounge forever or buy new from the factory; neither is pretty.

It's also possible to get a 603 engine from a 1986-87 300SDL (W126). It will be labeled "603.970," I believe, while the '87 300D (W124) has a 603.960 engine. There will be fewer parts that will cross over to the 124 chassis but at least the engine will be almost identical. (I've never seen a list of differences.)

Should you run across a "loose" 603 engine, try to get it bench tested to confirm that it actually runs and has good compression and all that before buying. Rebuilding a 603 engine is expensive: Metric Motors charges $8000+ for their rebuilt OM603s.

As already mentioned, California DMV usually looks at cars smog-wise based upon how they were originally built. There may be an "exception" procedure that you will have to discover. Should you ever do this project, please publish how you were able to change the car from "gasser, bi-annual smog check required" to "diesel, exempt."

Jeremy

Thanks Jeremy!

Yeah, I think this would be pretty awesome to do and I love Diesel so it would work out real well. I didn't even think about emissions until the previous poster and yourself mentioned it, I can't remember if diesels are exempt here in California or if it's after a certain year, i'll have to go to the DMV tomorrow and find out. I'm curious now lol

JordaanDMC-12 · #10 01-15-2010, 11:22 PM

Quote:

Originally Posted by scottmcphee

Careful which pump you pull up to when refueling. Get a D on trunk deck and get the diesel fuel only sticker at the filler lid... Then you should be good to put a 603 in there.

Got one in mine!

Yeah for sure, that would suck putting gasoline in it! haha That's awesome you did yours, did you run into any problems/ have to do any modifications?

babyjames · #11 01-15-2010, 11:30 PM

Dream car (right now, anyway)! Or how 'bout an R129 diesel?

Transplant candidate:

http://portland.craigslist.org/clc/cto/1554231747.html

Jay.

Jeremy5848 · #12 01-15-2010, 11:50 PM

Quote:

Originally Posted by JordaanDMC-12

Thanks Jeremy!

Yeah, I think this would be pretty awesome to do and I love Diesel so it would work out real well. I didn't even think about emissions until the previous poster and yourself mentioned it, I can't remember if diesels are exempt here in California or if it's after a certain year, i'll have to go to the DMV tomorrow and find out. I'm curious now lol

Diesels are exempt but there is a new law in California about to go into effect (or maybe it did on January 1) requiring diesels after some year (1997?) to be smogged just like gassers. In your case, though, the VIN of your car tells DMV that it is a gasser and they will expect it to pass a bi-annual gasser smog test, which will be difficult with a 603 in the chassis.

Ahhh . . . here it is, from the DMV website:

New Legislation
Effective January 1, 2010, smog emission inspections are required for diesel-powered vehicles manufactured in or after 1998, and have a gross vehicle weight rating (GVWR) of 14,000 pounds or less for original registrations and transfers. Biennial smog inspection requirements will be phased-in beginning with a registration renewal date of April 30, 2010.

That doesn't affect you, of course but you have to figure out how to get DMV to reclassify the 300E as a 300D. BTW, I have heard that the engine must meet the smog requirements of the chassis model year but I have no personal experience with the procedure.

The California Bureau of Automotive Repair's web site has a lot of details. There's plenty of on-line discussion about "referees," changing VIN numbers, etc. Definitely you want to check out all the details before spending money on the project.

Jeremy