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bobcat 743 lost all hyd movement

Discussion in 'Skid Steers' started by firedude26, Jun 27, 2019.

  1. firedude26

    firedude26 Active Member

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    i was grading driveway and went from reverse to forward and all controls just quit working, no lift or tilt no forward backward, there was a ticking kinda noise , not sure what went wrong or how to test , im thinking the hyd pump took a crap. any help would be great. i just replaced the motor, and there was a small leak coming from the pump, not bad though, and it didnt dump any fluid out when it stopped.

    thanks
     
  2. Ronsii

    Ronsii Senior Member

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    You might have spun the splined shaft from the motor...
     
  3. willie59

    willie59 Super Moderator

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    Yep, the 743 had a U joint connection between motor and pumps, that's the first place I'd look
     
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  4. Vetech63

    Vetech63 Senior Member

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    What Willie said ^^^*
     
  5. firedude26

    firedude26 Active Member

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    i just put motor back in it, and the joint seemed fine. i ran it for probly 2 hours or so since.

    i greased it up and all, whats the easiest way to check that with out pulling radiator out of the way?
     
  6. Vetech63

    Vetech63 Senior Member

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    It usually strips the splines on either the coupler or the pump shaft. From above it will look normal even if it is stripped internally.
     
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  7. Ronsii

    Ronsii Senior Member

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    could be it broke a shaft somewhere.... cause if you lost ALL hydraulics - lift/tilt and machine movment then that would indicate engine power is not getting to the hystat drive
     
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  8. firedude26

    firedude26 Active Member

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    i guess we will have to pull motor again, UGH this thing is killing me, let me ask this, the hyd pump is leaking anyway, do u pull that all out from the front? might be easier or make more sense to pull it out and check it all and have pump fixed
     
  9. Ronsii

    Ronsii Senior Member

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    More than likely like Vetech said with the worn splines... happens on lots of different equipment, usually at the pump shaft.
     
  10. willie59

    willie59 Super Moderator

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    I have to admit it was like last century when I worked on 743's, and someone can correct me if I'm wrong, but seems I recall one can service that u-joint connection without removing the engine, but I'm not real certain about that.
     
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  11. Vetech63

    Vetech63 Senior Member

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    You have to pull the engine or the pump. The engine removal is quicker and cleaner. You can grease it by performing a 4 ft long arm reach around. LOL
     
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  12. firedude26

    firedude26 Active Member

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    i just swapped the 1702 with a 2203 maybe the new power stripped it out, lol i really need to pull the pump and have it rebuilt, anyone in SE MI wannna job???
     
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  13. Vetech63

    Vetech63 Senior Member

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    Those splines wear quickly and most people won’t even notice how bad they are worn unless they have experienced the problem before.
     
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  14. Vetech63

    Vetech63 Senior Member

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    You may want to pull the pump since it is leaking anyway. The good thing is by doing so, you already have it out if you need to replace the driven shaft. You can get to the coupler bolts on the flywheel also. If you pull the engine and find your pump splines bad, then you end up pulling both when it isn’t necessary.
     
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  15. firedude26

    firedude26 Active Member

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    i was just reading to where there is a seal behind the spline on the pump, that maybe where my leak is, the forum said you can replace the spline and seal with it in machine??
     
  16. Vetech63

    Vetech63 Senior Member

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    The seal you can replace as it is an external seal with a snap ring retainer. The female coupler on the flywheel you can change out with either the pump or engine removed. If you need a pump shaft, I always build those vertically on a stand.
     
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  17. firedude26

    firedude26 Active Member

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    so since in not able to do the work, would it be easier to pull the pump or motor? i cant find any you tubes on removing the pump
     
  18. Ronsii

    Ronsii Senior Member

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    Pulling the pumps is pretty straight forward, just lift the cab, remove the linkages, undo all hoses/tubes to the pumps and unbolt it.. :) there are probably a couple little things I forgot it's been 25 years since I pulled one ;) but it's not brain surgery.
     
  19. firedude26

    firedude26 Active Member

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    ok ill ask the guy thats gonna do the work for me what he wants to do, i just had shoilder surgery yesterday so im out if commision for a few months for the heavy stuff
     
  20. firedude26

    firedude26 Active Member

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    OK UPDATE, just pulled motor , the bolt that holds the spline on the Hydro pump backed off and that was it????? i have a new spline, and yoke ordered, there really isnt any wear on either, i have them soaking now in parts cleaner, i cant believe that this happened im happy that it wasnt worse but i am going to change the seal so nom more leaks. the new parts are $450 im noit sure i wanna pay that or just use what i have???? also the dealer said this job would be 20 hours plus parts, i think they are screwing anybody, took motor out in 1 hour flat and that included BS time.