Heavy Equipment Forums Heavy Equipment Community

hitachi urg 50 leaking hydro oil

captain charlie ยท 2015-09-25 19:05

Not sure where the oil its coming from, but its leaking out from the top of the swing housing. Started out just a little last week and had to keep topping the tank up. Today I put in 3/4 of a bucket of oil to top it off and turn the machine on. I stood there watching the oil in the sight glass dropping. I check all through the inside compartments but no wet areas there to speak of. I pulled the cover plate at the bottom and its dry. I looked down behind the boom pin and no hoses were leaking but the base was wet with fresh oil. I'm thinking I have to pull the pump on the bottom. Anybody been in this situation before.

Replies6
  1. #1lantraxco2015-09-25 19:12

    Not sure from your description but it sounds like you may have blown the shaft seal on the swing motor?

  2. #2captain charlie2015-09-25 19:58

    Just going to check on that now.

  3. #3captain charlie2015-09-29 22:56

    Swing motor looks good. I checked the oil in the base and its black and at the high mark. After I pulled it I found grease still on top of the gear. The ring gear housing is still full of hydro oil. Wouldn't the oil leak down through the shaft and fill into the base oil. Anyways, I'm looking at the rotary joint now. It's at the same depth as the swing motor but under the boom frame. Not much room to move or pull the hoses off. Any hints on pulling this besides starting at the top and finishing at the bottom. Thanks

  4. #4lantraxco2015-09-29 23:08

    Sounds like you're headed in the right direction it's either the center joint or a hose connected to it.

  5. #5captain charlie2015-10-04 02:48

    Pulled the rotary joint and took it over to Flemings in Aldergrove, Jodi put it on the bench and opened it up, o-ring on the top was worn and dried out. Used a small pick to pull it out and kept breaking into 1 inch pieces. Got the money out of that one. He says the body was a little scared from previous repairs. New o-ring and seals, good to go. So that's the easy part, pulling and putting back into position really sucks, the plumbing on the bottom isn't so bad compared to the hoses on top, then having to reinstall the swing gear after. I could have done the rotary joint without pulling the swing gear but its makes life easier now its out.

  6. #6captain charlie2015-10-11 18:17

    Finally got the rotary joint and the swing gear in, all oiled up and re-greased good to go. Only thing I cant seem to locate is the torque specifications on the 8 (22mm) bolts at the base of the swing gear. The bolts are Hitachi 'M' series. I torqued them to 80 lbs. and I not sure how much more I should torque them to. I sure wouldn't want to snap a head off a bolt. The bolts are just 3 feet deep in the guts of the machine, I'd rather check them 3 times over 3 months. Any idea or leads to this question. Thanks