[choprboy]

XXyyy.zzz

XX - M = gas engine, OM = diesel
yyy - major engine type (family/development generation)
zzz - minor engine number (specific fitment, internal modifications, rating)

i.e. All M123 engines will have the same arrangement, number cylinders, basic block, and construction. Engines M123.456 and M123.789 may differ slightly in bore/head compression,crank throw, internal/external attachments, etc., which affect the final engine power rating. To add a bit more confusion... the same engine major/minor number fitted into different chassis may have different power ratings.

M130 engines come in both fuel injected and carbureted versions (unlike, it seems, almost every other MB engine which has a different major engine numbers for the injected vs. carbureted). The injected versions will not fit unless you are willing to do major cab and bell housing modifications (due to the injector pump hanging off the side of the engine).

An incomplete, non-exhaustive, quite possibly wrong in horrible ways, list of M130 engine configurations:
M130.920 - carbureted, 9.0:1, 120-140hp, 68-72 280S
M130.921 - carbureted, 8.7:1, 125hp, 250C?
M130.923 - carbureted, 9.5:1, 110-130hp, 70-76 250, 69-76 250C?
M130.925 - carbureted, 7.8:1, 110hp, unimog 404.0
M130.933 - carbureted? 8.7:2, 118hp, 68-72 250?
M130.980 - injected, 9.5:1, 160hp, 67-71 280SE, 68-71 280SEL
M130.981 - injected, 9.5:1, 170hp, 68-70 300SEL
M130.983 - injected?, 9.5:1, 170hp, 68-71 280SL
M130.984 - injected?, 8.7:1, 140hp, 68-72 280SE/280SEC/280SL

 

[choprboy]

OK. So if I understand you correctly. The M130.980 will not fit into my 404.114 without modifying the cab and bell housing due to the injector pump. Correct?

Guess I just got excited at the extra HP. : )

Thanks Guys

Yes, it will not fit (or so others have stated in the past, I have not had my hands on one personally). It should bolt to the bellhousing, but would require significant modifications to other systems that is probably out of the fabrication range of most people. As ACAD posted, there are other differences between engines, such as oil pans, but those are usually pretty easy to swap between engines.

 

[choprboy]

Hmmm... Interesting! So based on this info it would appear that my M130 which has engine block no. 130.923 was transplanted to my 404 from a 250 or 250C, but it has a 9.0:1 head from a 280S. I guess my engine is an M130 hybrid!

Yeah... seems that way... or my list is "quite possibly wrong in horrible ways"....

For a M130.923, pulling from a couple sources (I have never been able to get EPC to let me register and log in... so this could very well be just a bad of info), your engine -12-003717 would seems to have come from a MB 250 114.011 or 250C 114.023 and have had a 130-010-91-20 or 130-010-24-21 head originally (up to engine -12-005298) if it was a US bound.

Oddly... here is another 250C M130.923 engine with the "280S" 130-016-12-01 cylinder head...
http://www.benzworld.org/forums/vintage-mercedes-benz/1711834-1972-250c-engine-noise.html

Edit: On second pass... the 130-010 numbers given might be partially assembled heads (guides/etc.), not the bare casting number.