Swapping 603 n/a engine for a 603 turbo Project
 

I have a 1991 300GD non turbo.
I have purchased an 87 300D turbo car with 140,000 miles on it.
(I got the car at auction for $800 and it had the Trap Ox still on it. It was real sluggish. I called Mercedes emailed them a copy of the recall from 91 and they said bring it in. They replaced the trap ox with the special pipe then installed a New turbo and complete exhaust system from front to back All free!) I like free.
Anyway back to the project: I intend on swapping the 2 engines.
The 87 runs beautifully but it has the #14 head.
The 300GD N/A has the #18 turbo head.

So as well as swapping the engines I will be swapping the heads, using the #18 head on the turbo motor and taking the #14 head (since it has no cracks or leaking) and using it on the non turbo. Then place the newly "crafted" turbo motor in my 300GD.

Upgrades that I and considering/collecting for the swap.:
New higher capacity water pump as used in the 606 motors (direct bolt on).
New full gasket set including head, oil filter, etc...
As the G has no oil cooler and the turbo motor does, add an oil cooler.
Since I am removing the head shall I put in a new timing chain?

Unknowns and things to do while the engine is out:
Is an intercooler necessary?

I intend on removing the diesel computer and run it mechanically.

Though the vacuum is fine should I replace the vacuum pump anyway?

I have a brand new injection pump made for the 350SD that I could swap for the existing pump.

I am keeping the G transmission, Is it difficult/practical to pull just the engine and leave the tranny?

That is just the initial list of things that come to mind.
Suggestions ideas greatly appreciated.

Thanks
Mark

Nobody has any input?

Nobody has a "G" type.

I would not swap the heads unless the #14 has failed. There is NOTHING wrong with a #14 head that there is nothing wrong with.

I would not replace any gaskets that did not need it. If it is not currently leaking, you cannot improve the situation, you can only make it the same or worse.

I would not replace the water pump if it is currently working properly.

I would not install the 350 IP. It will make no difference.

I have no experience with a "G", but on a "car" it is easier to pull the engine and transmission as a unit. That is the factory recommended method.

Check the chain stretch. If it doesn't need it, don't mess with it. The head does not need to be removed to replace the chain.

Move the oil cooler over with the engine and find a place to mount it if you can. I have always left the oil cool attached to the engine when doing a swap.

140,000 miles is "low miles" for a 603 that has had it's oil changed regularly. All of the tasks you have listed can be done with the engine in the car when they need to be done.

Thanks for the input Greg. The G motor is the same as that found in the sedans. The 350td motor was used in the g in the mid 90s.
Thanks again
Mark

The N/A head is not same as a turbo head

I checked the head through my various resources and with MB all confirmed it is the turbo head.
I was told that after a time they started to make only the turbo heads which were used for the N/A and the turbo.

Mark

My goal is to make it as bullet proof as possible. So doing a little preventive upgrading is my way of knowing exactly what I have and its condition.

Do you think an intercooler like on the 606 is necessary with the 603?

I have owned and maintained many Mercedes over the years mostly diesels. I like how they are overbuilt and these upgrades that I suggest are my way of continuing that process by keeping it running at its best.
Mark

Progress on the swap
 

Making headway on the swap

more pics
 

To clear the large air intake crossover pipe, I had to file down completely the bolt hole on the EGR mount. I then tapped/threaded/plugged the opening with a large bolt cutting off the head and then capped it with and aluminum cover utilizing the remaining bolt hole.

Mark

sorry I did not see this prior to you beginning the swap...

I would have registered the donor vehicle and taken it to MB and had them do the trapox swap, and possibly gotten a new turbo to go with the swap... maybe even a new head. certainly would have gotten the trapox delete setup. is that what you did or did you get the delete pipe elsewhere?
oh well...
looks like progress though, be sure and shoot pics each and every step!

one of my 87TD's has it, and a bad head and turbo...
my fingers are crossed!!!

If you need the recall doc I have it somewhere.

Good luck
Mark

I wonder if the Recall resets the counter on the 18month roadside assistance?

While the head casting may be the same between turbo and late NA 603s, I'm skeptical that the valves and in particular the exhaust valves are the same. I would want to ensure that the EVs are sodium filled and have the larger stem/guide diameter.

Good point I will check it out.

Thanks.