Hi everyone, I have a 741 that I bought about 6 months ago. First major problem was no drive function but after reading some posts on here I changed the bronze filter and I got the drive function back. My issue now is the left drive motor is losing power after warming up. It is leaking where the drive motor meets the chain case. I pulled the motor and the carrier seal looks fine, no fluid was leaking out of it. The fluid in the chain case is dirty and I know it needs to be replaced but the fluid that is leaking is clean hydraulic fluid. I just ordered a seal kit and will be rebuilding the drive motor next week but wanted to see if there is anything else that I am overlooking. Thanks for any input. Pete
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antfarmer2
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I have never done one (yet) but have heard that the o-rings go bad and do this also that the motor are timed so make sure and to use blue locktight on the threads when putting it back together to keep it from leaking.
antfarmer2
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I would replace the seal from the motor to the chain case while your in there
thanks for the input. Do you know of anywhere I can get directions for the timing part of the rebuild? I searched the site but didn't find much.
antfarmer2
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I would look up Tazza in here his email is listed and ask for his help he is one of the best but is busy and differant time zone in AU
Thanks for your help. I found a repair manual for my drive motor on the eaton website. Seal kit is coming in tomorrow so Hopefully I can get to it in the next few days. In the meantime I need to switch some hoses around and figure out why the drive directions are reversed (Push sticks forward machine goes backwards) definitely took some getting used to... thanks again will post results when I get the seal kit in
antfarmer2
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I don't think the case seal comes in the motor kit
There is an Oring between the motor and carrier/gearbox on the chain case. Sounds like this is where it is leaking.
Glad you found the guide of how to put it back together too. If it is not filling the chain case, the carrier seal may be ok. When they leak, your hydro fluid goes down but your chain case oil goes up.
I got the seal kit put in the motor and I am still having power issues on the left side. I did not notice an o ring between the motor and chain case but after looking at my parts manual I see which one you are talking about. I will replace it tomorrow and give an update. Would that cause the motor to lose power when the temp warms up? I did notice some decent grooves on the plate that the groeler works on so now i am thinking it may be time to replace that drive motor. In the meantime I was able to put a coat of paint on the machine and that really cleaned it up. will post some pics soon. thanks for the replies Pete
The marks on the plates, what ones are you talking about? the ones that take the Orings? or the ones that the oil flows through to get to the geroler? one you can use a sheet of glass to sand out, the other you really can't.
Try swapping drive motors to see if the problem moves, if it does it's the motor if not it's the pump. If it's the pump, you can mostly freshen it up with glass and sand paper.
Here are pictures of area that had wear.......... http://i9.photobucket.com/albums/a67/CaseyLandscapes/Bobcat%20741/KIMG0073_zpse5363922.jpg ......... http://i9.photobucket.com/albums/a67/CaseyLandscapes/Bobcat%20741/KIMG0074_zps4bf65fe9.jpg ......... I changed the o ring between the drive motor and gearcase and the leak stopped. I haven't swapped the drive motors yet. The left side is still weaker than the right even though after replacing the oring it felt stronger than it did before. If I drive into a dirt pile and move the right stick forward the tires will spin. If I do the same with the left side the wheels move but dont spin. Lastly, If I push both sticks forward it seems like the right side struggles to spin as well.
A few marks are fine, that is a lot more than light wear..... That could be the cause of youe lower power on that side. Not sure how to repair that without quite a bit of work. Possibly contact loader parts source and ask if they have a good plate?
Thanks Tazza, that's what I figured. Has anyone ever gotten plates machined? Or would that throw something off in the motor? Just trying to learn as much as I can as this is my first skidsteer.
It won't throw the motor off, the issue i see is the Oring grove. If you get it ground flat again, that may be too shallow to accept a new Oring.
It is worth a try though, you may be able to get an Oring to match the new grove depth though.
kdfergie
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I have a bobcat 530 that loses fluid down into the bottom case, would my drives cause that? how hard was it to change them or to rebuild them? Where did you get the instructions? thanks
