Engines for Sale

Sunday, October 27, 2013

Russian MAP 2.5 cc Diesel

Russian MAP 2.5 cc Diesel

ModelMARZ Mk. II
Series / Serial No.s / n
Year of manufacture2003
Displacement2.45 cc (0.150 cu. In.)
Bore15.5 mm. (0.610 in.)
Stroke13 mm. (0.512 in.)
Power classDiesel
Type of carburetorFixed (no speed control)
InductionRear Valve
Inner bearingIf
Outdoor BearingIf
Crankshaft to crankcaseIf
Crankshaft on bronzeNA
FuelEther / Petroleum / Oil
ConditionNew in Box
CommentsSecond series of this engine we can consider best seller and now manufactured from Russia. Practically equals the original model, but have improved casting processes such as crankcase and diesel cylinder sleve is classic: a steel jacketed type with radial transfer slots, piston of cast iron, crankshaft on two ball bearings and intake valve at the rear driven by a false rotary crankshaft.

This is not considered to be a high quality diesel engine by most experts. During the running of this new example I discovered that it is strongly advised that the engine be examined for loose head screws. After only what was a very short first run my engine began running rough and eventually stopped. When I checked for the cause of this I soon discovered that the three head screws holding the head down to the cylinder had backed out by almost a quarter of an inch; allowing the head and contra piston move upward by that amount. Its a wonder that the engine would even fire under these circumstances.
It was difficult to tighten the head down with a tiny slotted screw driver, but I managed to get them tight enough for more runs. Before I run this engine again I will locate some socket head screws of the appropriate size and length, which will eliminate this particular problem for once and for all.
I will also remove the back plate and have a look inside to check for foreign material which may have been left behind after the manufacturing operations have been complete. It is not unusual; particularly for engines manufactured in Russia during the last regime.     

Uploaders' Comments (David Crocker)

  • Cathead Biscuit 
    Hey David, another great vid of what seems ro be another great little diesel. What would be a good first diesel for someone wanting to get into diesel engines? I can tune nitro engines pretty well and I'm looking to get my first diesel. Thanks.
  • David Crocker 
    Thanks! From my perspective I would have to say the English PAW with throttle control engines are easy to live with inexpensive and practical for RC flying, but messy like all diesels, You should also keep checking the head hold-down screws for tightness because, they can fail from metal fatigue in flight and destroy the engine. That actually happened to me when I started in diesels. Check out my vid (Starting and Running the PAW 2.5 cc Diesel).
     ·  in reply to Cathead Biscuit
  • valic000 
    Hey David! Is that the new engine I send some months ago together with the ohers? .The engine run wel on a 9X4 prop.My new Marz also hat problems with a too tight contrapiston.It shoud free up,when use moore runs,If it goes too tight at a hot run,I just uscrew a bit,so it jumps out of it stocked possition,and than turn in til the right compression is archived .Otherwise unscrew cilinder,use a wooden dowel,and force the contrapiston out,and with 1200 wet paper grind it of a tiny bit.
  • David Crocker 
    Yes Peter! It is the engine that I got from you last fall. It runs great for the first run and with a little use it will run even better. Did you notice where the head screws backed off and had to be retightened? Did you see the list of new engines that I just picked up at the EngineTradingPost?
     ·  in reply to valic000
  • David Crocker 
    Perhaps I will have to perform that procedure if it does not loosen up naturally. The pliers will work to a point; until I bend or break the "tommy-bar" as the English call it.
     ·  in reply to valic000

All Comments (7)

David Crocker 

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