welding a bronze bearing wear plate?

Discussion in 'Shop Talk' started by SouthernThunder, Jan 4, 2006.

  1. SouthernThunder

    SouthernThunder Well-Known Member

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    I took my PTO pump apart on the old Road Boss dump truck and found a fragmented bearing wear plate. I have all 3 broken pieces. It is solid bronze. Nobody around here can identify the model or come up with a replacement plate for me. So I have to either try and replace this or buy a new $500 pump. I was wondering if I could tig it back together and grind it down and try it? Do you think it would hold up? I'd hate to send the parts into my cylinder after I just rebuild it... Anyone know of a good used parts source for large trucks?
     
  2. ace admirer

    ace admirer Well-Known Member Supporter

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    wear plated at each end of a gear pump or swash plate on a piston pump?

    any numbers on pump? have you tried Baum hydraulics? brass can be brazed but it takes a pretty good welder to do it since the filler and base metal melt at the same temperature. wonder what caused it to break? or was it just its time?
     

  3. Hip_Shot_Hanna

    Hip_Shot_Hanna Well-Known Member

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    try a local machine shop , any decent shop should have some phosphor bronze they can machine your part from .
     
  4. SouthernThunder

    SouthernThunder Well-Known Member

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    They are wear plates at both ends of the gears in a gear pump. They are machined in such a peculiar way as it has 2 circular "v" grooves cut on one side and then one "v" groove cut on the otherside that is in the metal between the 2 on the other side. Very hard (and thus expensive) for a shop to do. Im not realy up to speed on the pumps but I think these grooves are to relieve pressure at the end of the gears because the nature of the pump is to push fluid out to the ends as well as the direction of rotation.

    I think they are both busted because of a bearing failure in the case caused by a low fluid level cause by a leaky lift cylinder. (Maybe not in that order.)
    At any rate I am going to try and replace the plates with flat torrington bearings that happen to have the same thickness as the wear plates. My only concern is that the factory went though a lot of trouble making all these grooves and passages in the wear plates-- I wonder what will happen to my flat bearing washers...
     
  5. Hip_Shot_Hanna

    Hip_Shot_Hanna Well-Known Member

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    By the sound of it they are there to the thrust from the gears and the grooves are oil ways for lubrication and cooling of the thrust washers , their job is to take the wear fron the moving gears and stop the ends of the pump case wearing , torington bearings might do the job if they can put up with the speeds of the pump , if you can get thrust ball bearings instead of needle roler type they will stand the speeds better, other than that, have them made out of phosphor bronze and be prepared to replace them when they wear out , (preasure drop ) , they will be extremely well lubricated so wear should not be a great problem
    the Layshaft in a manual gearbox usualy has bronze thrust washers and they realy have to take some thrust ,
     
  6. ace admirer

    ace admirer Well-Known Member Supporter

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    yeah, what Hip Shot said. i think its too critical to do a lot of repair on. i still say give the people at baumhydraulics.com a shot especially if you can find any numbers on your pump. if nothing else, you should get one of their catalogues for other stuff they offer. .