300 Turbo Diesel W124 conversion

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syncropaddy

Active Member
Joined
Dec 15, 2012
Messages
142
Location
Gods Country
Car
W124/W126/W201/R129
I have just picked up a W210 300 turbo diesel saloon with 150k on the clock with a view to using all the good stuff to convert a W124 to turbo diesel. Other than the engine, transmission and rear diff, what else do I need to remove from the w210 - which incidentally, is rust free.
 
If it's rust free I'd leave it alone & drive it.
 
Have a look on dieselpump.co.uk website. Plenty of what you need. Depending on what power you want to achieve I don't think there is much more you can remove from W210 and reuse in W124. Brakes not compatible and you'll need bigger ones . Maybe propshaft...
Good Luck!
 
If it's rust free I'd leave it alone & drive it.

Its rust free for a reason and that's because the car is in Ireland where we don't salt the roads. The market value of the car is not a lot and the road tax is €1500 per year .......

Its a breaker
 
E200 €710
e220 €951
230e €994
250d €1080
260e €1294
e280 €1443
300e €1494
e320 €1809

:(
 
I have just picked up a W210 300 turbo diesel saloon with 150k on the clock with a view to using all the good stuff to convert a W124 to turbo diesel. Other than the engine, transmission and rear diff, what else do I need to remove from the w210 - which incidentally, is rust free.

If your planning to run the engine on the w210 ecu, you will need nearly everything electrical from the donor car to avoid running in limp mode.

The w124 rear diff will handle the power no problem, also the w210 prop front section will mate to the w124 6cyl rear section.

The steering box is not the issue people think it is, a custom downpipe is all that is required to get around that problem.

One problem you will have is an intercooler, unless you want to remove the ac radiator there is very little room to fit one behind the stock bumper. It's not impossible but very time consuming.
 
I've got to do this very swap later this year for a forum member using the stock ecu, so looking forward to a few electrical headaches. :D
 
Thanks for that info. Can I use a stand alone ECU from a third party?

Realistically no, however I heard of people modifying the stock ecu to run the engine without any of the input's from the other systems (I'm not certain how the gearbox is controlled in this situation though).

Most people just fit the old mechanical pump from the om603 to do away with ecu's altogether, and run a manual gearbox.
 
How does that sit with emissions and does it affect the characteristics of the engine?

You will get slightly more smoke on hard acceleration, but nothing to worry the mot test. Depending on how the pump is set up, performance is improved.
 
Brilliant thanks. I have a 6 speed manual from a W210 compressor which I believe might do the trick. I also have a 5 speed from a W124 E220. Just need a flywheel and clutch assy and a pump!
 
Brilliant thanks. I have a 6 speed manual from a W210 compressor which I believe might do the trick. I also have a 5 speed from a W124 E220. Just need a flywheel and clutch assy and a pump!

The 6 speed is an awesome gearbox, a world away from the merc manuals of old. The only thing to be aware of when fitting this to a w124 is the lack of drive for the cable speedo.
 
How is it going anyway?

Sideways mostly.:D

It will get 40mpg if your gentle so I use it as my daily driver.

20160626_174631_zpsrtcfe1gs.jpg
 
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The only thing to be aware of when fitting this to a w124 is the lack of drive for the cable speedo.

How do I get around that?
 

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