Mercedes Benz 240D Engine

[CJ Johansson]

Does anyone here know anything about the 2. 4 liter diesel MB used in the 240D? I know it's 4 cylinder and rated at 67 HP, but that's about it.



I can get one (with the rest of the car attached!) for $500 and think it'd make a decent power unit for a genset (car was rear ended and totalled, but the engine is fine).



So, I'm wondering if anyone knows how reliable these engines are, if they've got any known headaches, etc. This one's an '82 with 375K miles.



Thanks,

-cj

 

[RedRam1]

The old 220/240/300 Mercedes engines are just about bulletproof. They have cast iron block and heads, and an inline (P7100 type) injection pump. I worked in my cousin's garage for a couple of years back in the late'70's early '80's, and we maintained several of those cars. I have rebuilt sevral very high mileage examples, and they don't seem to have any weak points. The only thing that ever seemed to wear out were the valve guides.

 

[Skydiver]

Mine broke.

My 300D non-turbo broke a timimg chain.

I had the chain replaced @ 120000 miles. The new chain broke at 165000 miles. Reason:master link improperly bradded or crowned. If i had of left it alone it would still be running.

This is the best auto engine made if you are only going to funerals.

Can be hard to start below 25 degrees f.

Tim

P. S. I have my old benz for sale on auto trader.com listed as a 1982 model. It is 1981.

 

[CJ Johansson]

Torque curves?

OK, sounds like it could be a decent engine. I've found a bit of info from links over on mbz.org, etc. , 67BHP @ 4000 RPM, 94 lb-ft torque @ 2400 RPM, but so far I haven't found anything like a torque curve.



For my generator application, I'd really like to run it at 1800 RPM, so knowing the torque here would be great. Does anyone know where a curve might be found (preferrable on line)?



Of course, it's got a Bosch inline pump, so I suppose it could be bombed kinda like a P7100 if I wanted a bit more torque at lower RPM, but I'm kinda feeling like that would be a trial and mostly error endeavour...



-cj

 

[Don M]

How big of a genset are you trying to put together in KW? How much would you use the genset? Just for back-up power?



Don~

 

[The patriot]

My parents had one. It was a dog, but reliable.

I wouldnt go over 25Kw with it.

Eric

 

[CJ Johansson]

Originally posted by Don M

How big of a genset are you trying to put together in KW? How much would you use the genset? Just for back-up power?



Don~

Well, I suppose it'll eventually be for backup and big loads. We're about $20K from the nearest power line, so it seems like making my own power would be a reasonable plan. We've got an excellent wind site (mountain ridge top) and face south for good solar (at 45 deg. latitude it's limited in winter, but OK).



The gen-set needs to be 20kW minimum to run big things like the air compressor and welders to keep the farm equipment going. 30kW would be max. I figure that if the torque curve is reasonably flat on the MB engine from, say, 1500 to 2400, and guess maybe 90 lb-ft at 1800, that gives us 30. 8 HP, which will be just about perfect for 20kW. Of course, if torque drops off faster, it'll be pushing it. So, the curves would be great to find...



-cj

 

[Don M]

Looks like you got it all figured out or at least have some research goin'.



The genset will use more fuel than you think running all day and night. I have run a remote powered home and the cost was killing me. Fuel, maintenance, rebuilds, etc.

Big costs. The 20k power line sounds good to me after all the stuff we went through. I only ran a 12K genset. Yanmar powered.

We used about . 7 gallons per hour. If your running 24/7 you go through fuel like gangbusters and your over 8500 hours per year in engine wear.



I like the idea of having some battery banks for storage and shuting the genset down except to charge. The only problem is you aint gonna get an inverter to handle 30KW of power. You could fire the genset up for welding, big power loads though.



If I had it to do all over again, I would go with the 20K route from the power company. After I used the time up dealing with the installation, planning, building it, etc. I bet I spent 20K or more in the long run.



These are just my opinions of course. Not trying to discourage you. If ya got the time..... it could be fun and you will learn a bunch. I did!



Don~

 

[bvanetten]

Mercedes car diesels are high rpm diesels. They don't like to be driven at low rpms for extended periods of time. Run them between 3000 and 3500 rpm for best proformance and general happiness. My wife drives our 84 300d around town alot and after 5 or 6 weeks of that it starts to ron rough and start hard, milage goes down also. I take it on the highway and give it an "italian tunup" and all's good for a couple of months. Keep the r's up and change the oil and they will last several hundred thousand miles. One owner ran up 1 million miles on his 1968 240d and Mercedes gave him a new 300d in trade. They use the 240d as a promotional item now.

 

[Cooker]

Italian tune-up



I haven't heard that in a while

 

[bvanetten]

I think their fun! People behind me don't

 

[The patriot]

I think youre good for 746 (?) watts per HP, so you should be safe up to 30Kw.

It's been a while since engineering school, but I think that's what it was.

Do you have running water near you? You could make some power from that too.

Eric

 

[AWM]

don't know about the MB engines, but most auto type govenors won't hold a steady RPM with load changes, I tried this with a zuzu imark engine, didn't work, bob

 

[Skydiver]

Italian tune up

I used to enjoy driving my wife's 300D after she putted around for 3 or 4 weeks. I think the govener was set for 5800 RPM. How do spell mega-smoke?

 

[bvanetten]

AWM is right. Here's an idea. Get a used cruise control unit off of a 300d or something and (if possible) have the CC unit run off of the tach instead of the speedo. That should eliminate the rpm problem.

 

[B. Gill]

is the engine from a stick shift or auto as in the case of an automatic the flywheel will also have to be changed as far the RPM range the engine will work fine between 2000-3000 and the speed control governor works pretty good

i have given very serious thought to have a 300d 5 cylinder drive a generator when we had the power crisis here in california which by no means is over yet.

please let us know how the project went

thanks

bob

 

[CJ Johansson]

Originally posted by B. Gill

is the engine from a stick shift or auto as in the case of an automatic the flywheel will also have to be changed as far the RPM range the engine will work fine between 2000-3000 and the speed control governor works pretty good

i have given very serious thought to have a 300d 5 cylinder drive a generator when we had the power crisis here in california which by no means is over yet.

please let us know how the project went

thanks

bob

It's a stick. It does have cruise, so I figure if the pump doesn't govern well enough, I can figure out some way to use that.

Originally posted by The patriot

I think youre good for 746 (?) watts per HP, so you should be safe up to 30Kw.

It's been a while since engineering school, but I think that's what it was.

Well, that's the ideal number, like anything else you learned in school, the real world has these pesky things like losses and inefficiency, etc.



And then, there's that problem with not knowing the torque curve. You'll get lower HP at lower RPM, no way around it since HP is just a derived value based on torque & RPM (HP = (T * RPM)/5252).



So, from what I know about the engine, 94lb-ft @

2400 RPM, I get 42. 95HP. Using 1. 5HP/kW we can run about 28kW. If you use a more conservative 2HP/kW, we're down to 21kW.



I'd bet that the torque spec at 2400RPM is the peak torque. Unfortunately, generators for 60Hz don't like to run at 2400 (well, single phase anyway, 3 phase is another story). A 2 pole alternator needs to run at 3600, a 4 pole at 1800. The lower the RPM, the longer stuff lasts and you generally get better fuel consumption, just like our Cummins engines. So far from responses, it sounds like 1800 might be a bit too low to get good solid usable torque without mods to the pump (it's a Bosch inline, so I suppose it has a cam plate like the P7100). Of course, I could always run the engine at 2400 and couple to the alternator with belts and the proper pulley sizes to run the alternator at 1800.



I still haven't decided if I'm going to do it. So far, all I've come up with is new alternator units for about $1500, added to a $500 engine, then a couple hundered more to get it all put together and we're pushing $2500. I can get a complete John Deere 40kW unit on a trailer for about $3000 from a guy I know, so it's not looking a good at the moment. If I found a used alternator for $500 or so, that would make it much more attractive...



-cj

 

[DBlaze]

Originally posted by The patriot

I think youre good for 746 (?) watts per HP, so you should be safe up to 30Kw.

It's been a while since engineering school, but I think that's what it was.

Do you have running water near you? You could make some power from that too.

Eric

Only if you run the engine at it's HP peak which I'm sure is not 1800 RPM. I would figure the engine good for 1/2 it's max rating.



I have a 30 KW gen set that is powered by a 2-71 detroit. I believe the rating is about 75 HP and it runs at 1800 RPM.

 

[bvanetten]

I don't know if this info will help or not. It's not the motor that you have but I bet it has a similar curve. I know that the motor below has about 185 ft. lbs. but I'm not sure at what rpm it is at.







Engine type Vehicle type Engine HP



OM617. 950 W116. 120 (300SDT USA) 1979 85KW(115PS)/4200 1/min.

OM617. 951 W126. 120 (300SDT USA) 1981 92KW(125PS)/4350 1/min.

OM617. 952 W123. 133 (300 DT USA) 1982 92KW(125PS)/4350 1/min.



? W123. 153 (300CDT USA) 1982 92KW(125PS)/4350 1/min.

? W123. 193 (300TDT J) 1981 92KW(125PS)/4350 1/min.

? W123. 193 (300TDT S) 1982 92KW(125PS)/4350 1/min.

? W123. 193 (300TDT D) 1980 92KW(125PS)/4350 1/min.