What engine for a W114: C250TD or E300D (TD))

[ChasesDragons]

Hi all,
The madness continues. I have in my possession yet another 1969 W114 250CE. The current engine is shot.

I want to install a Diesel engine to run Biodiesel. I am looking for an everyday car. Doing about 80 miles a day. I am hoping the simplicity of older running gear is going to give the W114 an edge in terms of ease of maintenance.

It will be a manual geared vehicle.

Engine choices are:
OM605 based 5 cylinder from a C250TD
OM606 Based 6 cylinder from a 1999 E 300 TD

Any advice? I think the final choice will be one of MPG (Very important), Weights, Power and longevity. I dont want the W114 suspension swamped with a heavy engine...at least nothing heavier than the current 250 petrol in it.

Many Thanks

 

[Dieselman]

I dont want the W114 suspension swamped with a heavy engine...at least nothing heavier than the current 250 petrol in it.

In that case stick with the 2.5 litre engine.

 

[ChasesDragons]

I see, so the OM606 based engine is heavier than the 250CE's petrol engine?

Any comparison of bhp, torque and mpg between the two engines would be appreciated.

 

[Dieselman]

Both the diesel engines will be heavier than the old 250 petrol engine.

250TD is 150Hp, 300TD is 177 Hp as standard.

 

[nick mercedes]

Any advice? I

Put a 616/617 (240/300D) engine in it.

1 Because it can be done in an afternoon.

2 Because it will bolt up to the gearbox/transmission, and mate up to your rad.

3 Neither of the other 2 will fit.

4 Bin the 114 and buy a 210 diesel to smoke around in.

 

[219]

The W114 chassis also carried the M110 twin cam six cylinder engine , as fitted in the 280E/CE - the six cylinder Diesel engine won't be any heavier than that unit , the 250 six cylinder engine ( can't remember if that is still an M180 , certainly a derivative at least ) must weigh just about as much as the Diesel six .

At most , you'd just have to fit the springs specced for the 280 model . Is your car floor change or column change ? W114's came with both gearshifts , I'm not sure if a W124 gearbox would adapt to the linkage ....

Mechanically , the W114 is very similar to the W123 series , at least as far as running gear is concerned - engines/gearboxes from a W123 should drop straight in .

The 2.3 litre M102 , as fitted to the W123 230CE successor to your car , could also be a good option offering reasonable performance and economy as well as still being quite refined despite 'only' being a four cylinder unit . This engine carried over into the W124 series and is easily found .

 

[ChasesDragons]

Thanks to all for the info. One of the main drivers in engine choice is good mpg and power for everyday modern use.

This kind of take out the original 617 - I believe that it does no more than about 28mpg? It was high on the list with the prospects of Vegetable Oil fuel. But it all crashed and burned.

I think the the difference in bhp between the 606 and 605 (177:150) and the mpg they can hand out (35:45) rules in the 605 - unless someone throws in the 606 again on the premise of being longer lived?

I think the M102 might struggle to compete, as a petrol engined variant.

The vehicle is floor-mounted auto. But thats going to be changed to floor mounted manual. I will keep you all updated

Thanks again!

 

[74merc]

I think a 605 from an E250 would be the best combination of economy and ease of installation. There was a guy in Dublin who specialised in this conversion which I looked at a few years ago. I'd love to do this to my W115 220 auto so will be interested in how this turns out.

 

[ChasesDragons]

Do you have any links or references for his conversions, to avoid reinventing the wheel?

Mine is in the hands of Nigel Ball down near Illfracombe. Normally, he breaks out in a rash if an oil burner enters his workshop, must have caught him on a good day. He is also working out a 300TD W208 Cabrio, for me. Now THAT is a harsh job!

U

 

[Druk]

He is also working out a 300TD W208 Cabrio, for me.

Which 300TD are you using, 606-910 or 606-962?

 

[ChasesDragons]

I am not sure. We have about two or three engines at this time. If I was intent on keeping the CLK , I would probably keep the one easiest to go superTD.

The Cabrio has only done about 32000 miles. My initial thoughts have been to create an excellent, unstressed long distance commuter, as the drive train and suspwnsion/bodywork is like brand new. Souping it up might reduce this goal.

 

[Druk]

I have two engines as well. The easiest way seems to be transplanting the 910 IP onto the 962 engine. I'm still exploring the possibility of swapping over the delivery valves between pumps.

Some very good reading here...

STD

 

[Druk]

I'm still exploring the possibility of swapping over the delivery valves

Should read 'elements'

 

[Dieselman]

Seems pretty easy to refuel the pump.
I was thinking about it not throwing engine codes and think as long as the additional fuelling is done at the pump, the ECU won't see any difference so wont throw codes anyway.

 

[Druk]

Are you talking about retaining the electric pump DM? I've been into the amount of input reqd by the ECU to keep things under control and decided that's a no-no. I'm going down the road of swapping it for the 070-03 pump from the 606 non-turbo and keeping purely manual control. The only thing that'll be missing will be the idle advance feature and I can live with that. If I have to loose maybe 10bhp by underfuelling then so be it. I'll gain nearly that back by having a manual box.

 

[Dieselman]

Add a boost aneroid and you can run it as intended, thus lose no power at all.