Bobcat 751,Chain box overfull

[stevethatsme]

Have a Bobat 751, The Hydraulic fluid is overfilling the chainbox after 3-4 hours of use, after reading about this problem we were convinced that the drive motors were leaking into the box, so we bought 2 brand new motors and installed them, we also removed the return filters and cleaned, but we are still loosing fluid into the box, I dont understand how else the fluid can enter the Box,Help!

 

[Bobcatdan]

Motors are not the cause. The motor carrier that the motor bolts to is. When you unbolt the motor from the carrier, the seal is right there on the carrier shaft. As long as the bearings fell good, simply remove and replace the seal. Do both sides because normally you can't tell which side is the cause.

 

[stevethatsme]

Motors are not the cause. The motor carrier that the motor bolts to is. When you unbolt the motor from the carrier, the seal is right there on the carrier shaft. As long as the bearings fell good, simply remove and replace the seal. Do both sides because normally you can't tell which side is the cause.

Thanks Bobcatdan, I did not realize the motors were not sealed,

 

[Bobcatdan]

Thanks Bobcatdan, I did not realize the motors were not sealed,

The motor carrier acts as the back plate of the motor. That's why when you unbolt it, the rotating group becomes exposed. Just be glad you have that style. The large frame machined like a S250, the seals are inside the carrier. On those its a total gutting to remove the carrier, then completely disassemble the carrier for two stupid seals.

 

[stevethatsme]

The motor carrier acts as the back plate of the motor. That's why when you unbolt it, the rotating group becomes exposed. Just be glad you have that style. The large frame machined like a S250, the seals are inside the carrier. On those its a total gutting to remove the carrier, then completely disassemble the carrier for two stupid seals.

Bobcatdan,well ,looks like we are removing the carriers after all, the bearings are shot, causing large amounts of movement at the seal, fun times ahead!

 

[Bobcatdan]

Bobcatdan,well ,looks like we are removing the carriers after all, the bearings are shot, causing large amounts of movement at the seal, fun times ahead!

Carriers arn't that bad to do, just a lot of work. You can get them out by only pulling the front axles to get enough chain slop to remove them. Personally I pull front and rear so I don't have to fight the rear chain.

 

[mmsllc]

Carriers arn't that bad to do, just a lot of work. You can get them out by only pulling the front axles to get enough chain slop to remove them. Personally I pull front and rear so I don't have to fight the rear chain.

Splitting the machine or pulling the engine doesn't help give better access at all? It seems like it would.

 

[Bobcatdan]

Splitting the machine or pulling the engine doesn't help give better access at all? It seems like it would.

751 are easy. The engine and the hydro sit behind the chaincase. There are three covers so you can get at everything. Pull the steer counsel out and its pretty open. Pretty gravy, would quote it at 30 hours.

 

[Tazza]

751 are easy. The engine and the hydro sit behind the chaincase. There are three covers so you can get at everything. Pull the steer counsel out and its pretty open. Pretty gravy, would quote it at 30 hours.

As Dan said, the carriers are pretty easy to do, i have pictures of how i used a hydraulic puller to press the bearings out of a machine i worked on somewhere.

 

[7LBSSMALLIE]

As Dan said, the carriers are pretty easy to do, i have pictures of how i used a hydraulic puller to press the bearings out of a machine i worked on somewhere.

check pricining oftem times. carrirer cheaper to replace than rebuild.

 

[mmsllc]

check pricining oftem times. carrirer cheaper to replace than rebuild.

Hey Bobcatdan, What would you quote for chain repair times or wheel bearings on all four positions?

 

[7LBSSMALLIE]

Hey Bobcatdan, What would you quote for chain repair times or wheel bearings on all four positions?

smallie here. couple questions? are ax seals lekining are brgs shot. excessive end play? chains strecheted. this is acuatuallly a fun job. its quick its simple its basic menacic. you need to be set up for liftining . SAFELY. unit goes up and blocked. lift arms come off pkg rmoved separate main frame from chain case. now you got a box o chains brgs and axles. and once its done its done should never haveto revisit it seems dauntinig don't it. not that bad the other option is to do one at a time. spend years chasining leaks and brgs or do it once do it right and be done. been here done it 40 about right might come in under that. keep in mind enviromatal as in salt feterlizer etc. neglect. tosses all that out the window does not change the fact that it has to be done.