OM606 NA Conversion Project
 

Newbie to this forum! Great info!
After trolling on this forum and several others (off and on) for the past 2 years (after Katrina) looking for a 3.0L 6 cyl. diesel engine for a conversion project, I have decided to investigate deeply the OM606 NA with the 722.5/6 auto transmission. Keeping the engine and trans together should solve the electronic ECM and TCM problems. However, I do have a few questions for those of you in the know.

Does anyone have the specs (hp, torque, bore, stroke, etc.) on this engine? I see that the HP is 134 but at what rpm?

I have read on this forum that you cannot put a turbo on this engine without replacing the pistons and connecting rods. Does the crank need to be replaced as well? Does anyone know a rough price of the turbo pistons and conn rods?

Any help will be much appreciated!

The bore/stroke/displacement specs are the same for the turbo and naturally aspirated versions of the 606, however, as a general rule, only engines built to be turbocharged should be.

Which chassis are you planning to install the motor in?
The W124 chassis had the 606.910 (N/A) in '95, and had a mechanically-controlled injection pump.
The W210 E-class chassis had the 606.912 (N/A) in '96 and '97, and the 606.962 (turbo) in '98 and '99. Both engines had electronically-controlled injection pumps.

Of good note, the N/A injection pump will not perform well when used on a turbocharged motor. Thus, if you do plan to convert a N/A motor, you must use the IP from a turbo motor, an IP which only came electronically-controlled. If you are planning to install it into a W124 chassis, you will encounter some problems. Perhaps you could use the mechanically-controlled IP from an '87 300D Turbo, which had a turbocharged 603 of the same displacement.

I'm thinking your best bet is to find a running 606.962 and save yourself the hassle.

If you do buy a used engine and transmission, be sure to get *all* of the electronic modules. Don't forget the vacuum pump under the rear seat; the engine computer won't be happy without it. Ripping out the wiring is probably also advised.

Good info, thanks alot!

I agree about the NA to turbo building. I had read that the turbo engines were very, very rare so, I thought that I might be able to do it but it is probably too expensive as well.

I do not want to insult any of you Benz people but the vehicle that I want to put the engine and trans into is not a Mercedes at all. Hence the need for the engine, trans and all electricals. A wrecker most likely!

Matt, thanks for the tip on the vacuum pump. I guess I would find that when I start pulling all the wiring out of this "future wrecker".

Does anyone know the length of the OM603/606 from the front of the fan to point on the rear of the engine where the trans bellhousing attaches? A rough measurement is fine.

You can get a 606.96 from pgauto.com or silverstarrecycling.com for $4000 plus freight. You need a transmission and electronics to go with it but you'll need that with a 606.91 as well. Point is, it will cost a lot more than $4000 to beef up a 606.91 to handle a turbo.

Sixto
87 300D

Sixto, thanks for the info. I really appreciate it. I am still fairly ignorant concerning the Mercedes engines. And yes, I thought it might cost more to rebuild an older engine than to just buy a newer used engine and trans.

If I were going to attempt something like this, I'd try to get the IP from a turbo 603, disable the 606 flaps and get rid of the engine computer. I'd also not attempt to put a 722.6 transmission into the car.

Transplanting the engine computer is asking for trouble. For one, as I already said, other modules communicate with it and some of them know the VIN. One of these modules receives the IR input from your key, so that will no longer work. You may be able to get the RCL to work the locks without the engine computer, and hack up some way to shut down the engine.

I don't know what it would take to get this done, and am somewhat curious in an academic way (hopefully the curiosity will stay academic).

I know a fellow who just pulled a 603 out of his SDL. He says 31.8" from the water pump pulley flange to the tranny flange. Factor the thickness of the fan and clutch and you have the whole thing. 606 should be somewhere between the same and exactly the same.

Sixto
87 300D

Matt
That is a good point about the key ID, I had not thought of that one. There may be other security blocks as well, like you said the VIN. I thought with the engine and trans pair I would avoid problems between the engine PCM and trans TCM. I will have to do some more research.

Sixto
Thanks for that info, it is really helpful.

Are you planning to put the engine in the Silverado in you signature?
Not a good idea. You'll lose lots of performance and won't have much power other than drive it on level ground.

Off topic - afgunn, send me an email or pm on where you got the exhaust for your Silverado.

Sixto
87 300D

lietuviai,
No, not the Silverado at all, I agree too big and heavy. An 03/04 Dodge Dakota which is about the same weight as the cars that the Mercedes diesels come in.

sixto,
The truck already had the exhaust when I got it. Sorry.