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JD 990 Hydrulic Oil Cooler

J Mayer ยท 2016-10-12 17:49

I am looking for advice on repair or a used replacement . A 3400.00 new one is not an option ... I was considering constructing on from hydronic baseboard heating "fin tube" w / 1 1/2" headers so connections to the machine hoses would be the same and mount the assembly inside of the orginal cooler frame after I gut the tubes out .... Advice ?? Ideas ?? Anybody have one ??

Replies4
  1. #1lantraxco2016-10-12 18:56

    No offense but that dinosaur should be in a Deere museum. The fuel consumption must be awful. Anyway, give these guys a shout, long ways from you but they build and ship anything: http://radiatorsupplyhouse.com/ No baseboard tube please, I seriously doubt you would get the heat transfer needed to cool that open center system.

  2. #2Delmer2016-10-12 22:01

    I'm not sure fin tube would be my first choice. It seems thinner than even type M copper, I believe the tube is expanded to snug up to the aluminum fins for good contact and heat transfer. Hydraulic coolers that I've seen have all been smaller diameter steel tubes in the fins (smaller diameter has a much higher pressure rating for the same wall thickness) brazed into relatively thick steel tube headers. What do you use the machine for? If it's used for only a little at a time, bypass the cooler or replace it with a smaller cooler from a junkyard and watch the temp gauge. Is the old one repairable by sealing off tubes, even if it's a bunch of them?

  3. #3J Mayer2016-10-13 20:29

    Were not a "production operation "--- excavate large ponds and dredge marinas . We may have the exaiayinf cooler repaired . Looks like 1 tube near the bottom and 2 about 6 inches from the too , total of 3 tubes . Appears to be factory cooler with no previous repairs . I have been told the tubes wear from the inside due to erosion and if any are leaking the rest are not far behind . Yes , I have considered a new "smaller " cooler . The resivor is 95 gallons . I have also condsidered a remote cooler with an electric fan . They are plenty full and much less $$. The copper fin tube appears to not be an option ...

  4. #4lantraxco2016-10-13 21:11

    I tend to be doubtful about wear from the inside, hydraulic oil is typically fairly clean and laminar flow means that the flow along the tube walls is usually much slower than in the center unless like more modern coolers they have devices that actually create turbulence to increase heat transfer to the metal. Now erosion on the outside from debris being pushed through by the fan I'll buy any day. If you have the room or don't mind mounting it externally one of the electric fan coolers would be great, no heat from the engine and no oil/dust/goop buildup on the cooler fins.