Changing engine in a W123

[stecheetham]

Hi. I wish to replace the engine in my 200T automatic with a 3.0 ltr diesel out of my other 300TD so that I have a 300TD auto. Is this quite a straight forward change ? will the 3.0 ltr deisel engine fit straight onto the auto box ? Will I need to fit a spigot bearing or remove one ? Any help most appreciated

Thanks

SC

 

[Mikesmerc]

Not sure, but if it does fit will the diesel be reving a bit high high with a auto box designed for a petrol or is it that the differential is geared differently??
Regards
Mike

 

[stecheetham]

I don't know. But am assuming that they only used the one auto box. I have looked through the w123 hand book and they show 3 gear boxes on the w123. a 4 speed man, a 5 speed man and an auto box. I know that a good few parts will need swapping over but I would expect the engine to go right in. They do list a 3.0ltr auto so it could be good for it. I do need more advice though as I am not a mechanic, only a novice with a bit of an idea.

SC

 

[guydewdney]

the diffs are different. definately. (i did some research for my 114 racer - i was trying to find the lowest ratio diff i could - and iirc it was a large engine diesel 123...

 

[stecheetham]

I have a complete 300TD as a doner car.

 

[joeywarren]

300TD has a 2.88 diff, and most petrol versions have 3.46 or above. Makes for a very big difference at 70-mpn I can tell you!

The autoboxes are the same. Not sure about the fitment though.

Your 200T will have a short geared diff (like 3.68) and I'd recommend changing to the 2.88 donor one. Otherwise your new diesel will rev high, but also be quite storming off the lights.. Up to you, but I'd swap out.

let us know what you do and how it goes.

p.s. if you choose not to do this, let me have your 2.88 diff ;-)

 

[190]

Spigot shaft bearing will need to be removed from the crankshaft so the torque converter will fit on.