Russian Mk 12 B

Russian Mk 12 B

Circa Mid 1960's
In Stock at the Trading Post

Design History:- 
Designed and manufactured in Russia in the mid 1960's


Design Features:-
Early versions featured a removable front housing;
later models featured a single piece crankcase;
rear induction; and
crankshaft supported on ball bearings

Specifications:-

Fuel:	Ether/Petroleum/Oil
Cycle:	2T
Data
Cylinders:	1
Displacement:	2,45 cm³
Bore:	15,5 mm
Stroke:	13 mm
Weight and Dimensions
Other Information
Model Year	1980
Manufacturer
U.S.S.R  (C.C.C.P.)
Distributor
U.S.S.R. (C.C.C.P.)

Comments:-

"A nice try to copy a proven design"

This is a fairly rare MK-12 b engine made in the former Soviet Union. It was not easy to find information about this engine, but as I love to digging about for data on old model diesels I found the following information. 
There were several versions of this engine. The early models had a split crankcase, like the Webra Mach1.  It was probably a copy of that famous German engine. 
The early types came with a black or red anodized head..also the early models had 3 holes to screw the head tight to the crankcase. The later were blackheads and had a natural aluminum finished: heads had 2 holes on the top for the special tool to assist with its removal. The early models were introduced around by 1964 and the later series were build around 1982.  I don't know exactly, where the changes start and when the last engine was produced. 
The quality was not really good: in my eyes it looked like a hasty cheap manufacturing job; the castings are not in my opinion a very good quality and not that  nice to look at. The needle on my engine is too loose, but even more serious; the piston's fit was far to tight and the finish rougher than desirable. What is needed is a smooth "glass like" shiny finish on the piston and on the cylinder walls. 
After enlarge the upper part of the cylinder slightly and polishing the mating surfaces our engine starts to feel right. Also the big end had already some slack in it, which is not a good sign for a new engine.
After a test-run it looks to be not too bad a runner at all. 
I will make a bronze bush for the big end and I will fix the needle. 
So after making some cosmetic work, I will make a new spinner like the ones on the early types, it was looking not bad at all.
Since I collect Russian diesel too....It just had to be in my collection and I am happy to have it as a runner.
I understand, there was a B and C version as well, but I am not sure what is what~~maybe the A version was a very well build engine like the very first Rhytem team-racers were: made to a very high standards~~I am not sure. Perhaps they were reserved only for the Russian competition teams and the MK-12 b is only a shadow of what it was to be as a first place winner... a great Russian team-racer with great potential....but only available to the "happy few".... those who competed for the Russian Team".




http://youtu.be/urF9GZXsKxc 

This posting is prepared in collaboration with YouTube Channel valic000 Visual material and observations are by valic000