Author	[Modern View]
Todd Asbill 01-14-2013 19:29:11 69.46.60.148 Report to Moderator	My recently purchaced jd 450c 6 way blade. New hyd pump locked up and broke shaft that drives the pump. I took Hyd pump apart and found that the gears had been shaving the inside of housing. I found aluminum slivers from housing all in the gears so I assume that is what caused it to lock up. The question is what is causing the pump to do this? John Deere are really proud of those shafts is there any aftermarket shafts out there. [Reply]   [No Email]
Roy Suomi 01-16-2013 16:55:11 76.190.196.2 Report to Moderator	Re: JD 450C hyd pump problem in reply to Todd Asbill, 01-14-2013 19:29:11   Years ago I ran into a similar problem..If memory serves, there was a relief valve or poppet valve that was hammered and pieces parts were flowing thru the system causing the pump to self destruct.. Pull the control valve out and check all reliefs and poppet valves for problems..The return filter was removed at some time and junk was being recirculated..Also check the system relief for stuck condition.. This relief is on the inlet to the valve in the end cover.. [Reply]  [No Email]
Todd Asbill 01-15-2013 06:17:07 69.46.60.148 Report to Moderator	Re: JD 450C hyd pump problem in reply to Todd Asbill, 01-14-2013 19:29:11   This is the second new pump the first one did same thing so my first thought was a faulty pump. Then when the second pump did same exact thing now i think there may be a problem else where. [Reply]  [No Email]
Roy Suomi 01-23-2013 16:58:06 76.190.196.2 Report to Moderator	Re: JD 450C hyd pump problem in reply to Todd Asbill, 01-15-2013 06:17:07   I don't remember , is it a Gressen valve ?? Try calling Surplus Center in Nebraska. They have some real sharp customer service people that know their stuff.. Maybe they can help.. [Reply]  [No Email]
Todd Asbill 01-15-2013 17:49:14 69.46.60.148 Report to Moderator	Re: JD 450C hyd pump problem in reply to Todd Asbill, 01-15-2013 06:17:07   Possibly found the problem. This dozer according to the books requires a 1750psi relief valve the valve that is in it is a 2250psi valve. Now I am looking for a place to get the 1750psi relief valve. any ideas where to start? according to my local JD dealership they are not available. [Reply]  [No Email]
kyhayman 01-14-2013 20:04:14 99.197.64.57 Report to Moderator	Re: JD 450C hyd pump problem in reply to Todd Asbill, 01-14-2013 19:29:11   Shaving of the pump body like you describe is a pretty good sign of bearing wear. Lets the gears track looser and looser. The more shavings the more wear. Good systems flush, and a trip to the pump shop. As to the shaft, perhaps a driveline shop or machine shop can weld and balance the shaft... or a used one. For the pump, I'd take it to a good hydraulics shop and have them go through it. They may be able to repair or source your shaft as well. [Reply]  [No Email]
Lloyd East 01-16-2013 14:57:41 75.89.139.198 Report to Moderator	Re: JD 450C hyd pump problem in reply to kyhayman, 01-14-2013 20:04:14   My brother and i have a 450c loader that did the same thing three times. i think it must have the same problem. First time it broke the shaft and second time it broke the center part of the pump. My brother bought another pump off the internet and put it on there and it blew the threads out of the outlet of the pump. I would think you could rebuild the pressure relief valve. It is probably just stuck. That is probably what is wrong with ours but we haven't worked on it any more. [Reply]  [No Email]
Todd Asbill 01-19-2013 17:43:46 69.46.62.203 Report to Moderator	Re: JD 450C hyd pump problem in reply to Lloyd East, 01-16-2013 14:57:41   Its fixed. Someone had had the relief valve out at some point in time and did not have the poppet at the bottom of relief valve in correct. The system was over pressurizing causing the pump to lock up then the shaft would break. [Reply]  [No Email]