Ben MacLeod
New User
Hey guys, I'm very good with engines, electronics and mechanical issues but I'm not Hydraulic savvy. I bought this tractor (IH 784, 4wd with 2250 loader) a couple years ago and the hydraulics were weak. I replaced the pump, filter and hydraulic oil and the hydraulics have been very strong ever since. This fall, I discovered coolant in the oil and so did a major engine overhaul. When I drove the tractor out of the shop, all hydraulics were as strong as ever. I attached the loader and mounted my snowblower. I ran the 3pt hitch up and down and the hydraulically controlled directional chute. Also the pto. All worked excellent. We got our first major snowfall here a couple days ago and so I fired her up. I discovered that the 3 pt hitch and the loader would not lift. I increased engine rpm and it was over half throttle before either struggled to lift. I figured everything was cold, though it was only zero degrees (32 for my american friends)so I let it warm up a long time. No difference. I pulled it into my heated shop and discovered the steering would not work below half throttle either. I left it overnight and next day no difference. I drained the hyd fluid and it's slightly cloudy but not what I would call bad. I removed the filter, put the hyd fluid back in and tried it again to eliminate the filter. No difference. I pulled out the relief valve and disassembled it. Spring looks good as does the seat etc. I cleaned and reassembled and still no difference. I pulled the valve beside the relief and started the tractor... Lots of flow. No difference. I pulled the pump off and checked the gears. The woodruff key is still intact and I cannot make the drive shaft for the pump slip in the pressure plate (this would be loud when running anyway and there is no such noise). I am now at a total loss... All signs point to pump except that it happened overnight and besides that, the pump has maybe 200 hours on it. Anyone have any input on this? Sorry for the length but wanted to supply as much info as possible. I need this tractor....