Engine Swap: M116 from w116 Replacing M110 in w123?

[Lukas]

Hi all,

One of the options I keep pondering for the rusty 350SE is, rather than extensive body repair that it needs, just sticking the (good and low mileage) euro M116 engine into another, good body. The obvious choice is of course another w116; but it just occurred to me that the w123 uses the same(?) M110 engine as the w116, so does that mean that:

a) The M110 and M116 have the same mounting points, and thus by extension.....
b) An M116 could be put into a w123?

What about the transmission? Diff? Instruments?

This has been spurred on by this ad: AllClassifieds, although there is definately no rush - just a hypothetical at this stage.

Ta

Lukas

 

[SELfor50]

Hi all,

One of the options I keep pondering for the rusty 350SE is, rather than extensive body repair that it needs, just sticking the (good and low mileage) euro M116 engine into another, good body. The obvious choice is of course another w116; but it just occurred to me that the w123 uses the same(?) M110 engine as the w116, so does that mean that:

a) The M110 and M116 have the same mounting points, and thus by extension.....
b) An M116 could be put into a w123?

What about the transmission? Diff? Instruments?

This has been spurred on by this ad: AllClassifieds, although there is definately no rush - just a hypothetical at this stage.

Ta

Lukas

Anything's possible. Just depends on your budget.

Seriously though, Chris from MB Spares has mentiond previously he's wanted to put a short stroke M117 5.0L in to a 123 of his.
I don't see any reason why with a little bit of creative puzzle work you could fit it for sure.

I'll be back in the shop tomorrow to clean up, if you like I'll throw it open for comment.

Cam.

 

[John S]

A number of Mercedes bodies using different sized engines have alternate mounting points already built in for the rear gearbox support and the front supports, eg the W109, W116 etc, but the W123 was never available with a V* option, only straight 4 or 6 cylinder engines. Consequently you may have to make up a number of unique mountings and supports for the swap you want.

 

[B13]

A few months ago in Mercedes Enthusiast UK magazine some lad had installed a 560 engine into his W123. Its mainly all bolt-in besides some custom engine mounts and an obviously custom exhaust system.

I.

 

[SEL_69L]

Probably a nicer swap would be the ALLOY M116 or M117 from a W126. The W123 would have approx. the same weight over the front wheels as with the old M110 engine, and so the turn-in response from the steering would be less obviously affected. The braking ability would be less obviously affected also.

I have inquired some years ago about engine and gearbox mounts, and they are surprisingly cheap to fabricate. At that particular time, I was chasing up the possibility of fabricating suspension blocks for my 6.9. If I remember, at the time, it was going to cost me about $350 for a set of four. A much greater problem to overcome may be mods. to sheet metal in the engine bay or the firewall.

I came across a chappy recently, ( does not contribute to any website that I know of), who said he had a very good 450SLC, which had a ruined engine removed. He has installed a 5.4 litre quad cam Ford engine transmission and back axle. Has spent about $25,000 so far, and estimated about 6 months from completion. When asked why a SLC?, said that he just always loved the look of them. This way, I guess, he still keeps all of the electronics integrated. The way I see it, he still has a Ford, just a nice looking one.

 

[Lukas]

Hi all,

Thanks for the info - John S' statement about no V-engines in the w123 is what more or less occurred to me over the holidays, so the consensus of "possible, but with some customisation likely required" sounds reasonable.

Ta

Lukas