i checked my swing motor gear oil, it was a little low on the stick but took a gallon or so of gear oil to bring it up to normal on the stick. The next morning the the swing motor level was back to low and i had gear oil mixed with grease running out of my swing gear seal. I'm thinking a new seal on the swing motor. Any insight ? My mechanic wants to replace the whole swing motor, this seems excessive as it runs great at 9,000 hrs.
Pull the swing motor and gear box and replace the seal unless there is a gear failure that would justify spending that cash. I would replace the hyd motor shaft seal to while in there and have a look at all the components while you have it apart. Then you'll have to clean the swing gear area of oil and grease and refill it with new grease. If you search around the forum there is a few posts on this and I think some have pictures.
As I recall the big pinion gear unbolts from the swing motor shaft. You can change the seal without dismantling the gear box.
John C, the pinion gear is one piece with the shaft. There is a sealing surface directly above the gear that the seal contacts. RockymtnEXMt, pull the swing motor off the reduction unit, then pull the reduction unit out and turn it upside down. There's a seal housing that holds the seal with about 7? bolts. The housing and seal slips over the pinion gear. Replace the seal and the o-ring under the housing. And like AndrewC said, replace the shaft seal on the swing motor. This is a fairly simple job but when installing the reduction unit into the machine make sure you get the bolts properly torqued.
I think what John means is the motor unbolts from the gear unit which is correct. I believe the seal is the same as the ones I have done which is fairly easy to do but I usually pop the motor apart and have a look at it and do the same with the gear unit, with your kind of hours its easy to do and provides a piece of mind. Of course you can pull the motor and gear unit as one, change the seal and drop it back in if you are in a hurry.