I thought I'd share my adventure with my 880 hyd pump. It would barely lift anything.The central pump body was undamaged, luckily. The two side plates were both heavily scored where the drive gear ran and somewhat scored where the driven gear ran. I had the two side plates planed for $60. I replaced all four bearings and seals, putting seals facing inward (unlike the book which says 2 in and 2 out). When I put the bearings in I rolled the lip on a small one and had to replace it. The pump would not turn at all when assembled. I finally figured out that the side of the drive gear had picked up a very, very tiny amount of material from the end plates. It was minuscule. Could this be the problem? I removed the clips and pressed the gear off the shaft. Then I lay the gear flat on emery paper and patiently worked it until it looked flat and I could run a knife blade over the gear to be sure there was nothing sticking up any more. Putting it back together was tricky to line up the shaft and the key. We couldn't turn the gear on the shaft. We got it as close as we could, then put the shaft in the vice endwise and turned the gear to line it up by striking it gently with a hammer and brass punch, then finished pressing it on. Upon reassembly, the pump turned readily. It really was this almost microscopic cluster of a few bits of metal picked up from the end plate. I haven't run the tractor so am not yet positive that it is fixed right, but I'm confident so far. I hope this doesn't bore you experienced mechanics. It's the first hyd pump I've ever worked on.
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