I have a cat112 2m84 serial # it has a lite blue paint under the cat yellow.the radiator  has rd4 engine serial number is4g2561.im assuming  this is not the correct engine for the grader? Would the grader be a 1939 and the engine 1936?

not necessarily you can have a older engine in a later frame. or it may have been a re-power. if engine production was ahead of machine production you would get different ages.
around ww2 all things not military were painted the light grey as everything else was olive drab. grey was the industrial engine colour.

and in the big scheme it doesnt matter its not like its a 55 Chev. its very common for plant equipment to be re-powered as it was quicker than a rebuild when time is money. so they would swap a engine just to get a machine working again and rebuild the original as time allowed for a spare. mining companies and the military still operate this way so does the aviation industry.
many cars are made with engines that are months older than the car bodies because of the fact they are made from components from around the world.

trainzkid88 wrote:

not necessarily you can have a older engine in a later frame. or it may have been a re-power. if engine production was ahead of machine production you would get different ages.
 

Cat serial numbers matched so if they don't match it was a re-power especially since as stated the engine is out of a RD4.
None of my D6's have the original engine and I often wonder what happened to them.
It will most likely be the same engine model though. D4400.

MikeHanson post=237517 userid=4116I have a cat112 2m84 serial # it has a lite blue paint under the cat yellow.the radiator  has rd4 engine serial number is4g2561.im assuming  this is not the correct engine for the grader? Would the grader be a 1939 and the engine 1936?

I would love to see a picture of the the ol' gal.
Yes 2M1 - 2M225, 1939, was the first year of the No.112  D4400 52hp
Yes 4G1 - 4G3662, 1936, was also the first year RD4

Do you want to connect elements of two different models? Maybe I didn't quite understand you correctly, but it seems that this is not a very good idea. Different parts of the models may not fit each other and only spoil the whole mechanism for you. So I'd be more careful if I were you. You can order what you need on machinerydealer.co.uk , and do not worry about anything. I use this service myself when any equipment breaks down. Good luck to you and your tractor