Tractor Repair: MF 165 diesel, perkins diesel engine, massey ferguson

Question
I have a MF 165 with the serial # 9A7944I, it has a 4 cyl diesel engine in it. There is no tag on the intake manifold. By the serial # can you please advise of the year model and which perkins engine it has. I believe it to be a AD4.203. Also please tell me where will be the least expensive place to buy an exhaust manifold. Lastly, when the pto is engaged the shaft turns but when you put a brush hog on the tractor it will not turn it.However it makes no bad noises loaded or unloaded. I believe the pto clutch is out but my friend swears that it is just an adjustment.PLEASE HELP THANK YOU GREATLY

Answer
Hi Jason
  Your MF165 was built in 1969 The Nebraska Test has it with 52.42 PTO HP. & 44.9  drawbar HP. It would have the AD4-203 Perkins diesel engine in it. The MF165 came with two different types of PTO systems. One is the manual PTO where the clutch has to be released before you can pull it into gear other wise it will grind when the gears try to mesh. The other type is the Independent PTO. It has a multi-disc clutch pack in the rear center housing it is hydraulically engaged. It can be engaged without releasing the clutch. According to which you have would determine what is causing the problem of the PTO clutch slipping. I am pretty sure your friend is wrong about it being just adjustments.  
  We will start with the Manual PTO It would be the PTO Clutch disc in the dual clutch slipping under a load the Fix for that is replacing the PTO Disc The tractor has to be split between the engine & transmission to do that.
  With an Independent PTO it could be the multipower & Independent PTO pump weak it could be seals in multi-disc clutch Or the disc their self are worn out. It usually is a combination of all 3 of these thing. If I can be of further help email at ( daustin62@aol.com ) Also visit my Massey Ferguson web site for other information on your tractor. ( http://hometown.aol.com/bigdean62/index.html )   Big Dean