Wanted a hydrostatic motor for a 700-720-721-722 Bobcat Skid Loader

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ChandlerW

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Oct 8, 2013
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I'm looking to buy a hydrostatic motor for my project skid loader. Mine self destructed. Only need one.
 
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ChandlerW

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Oct 8, 2013
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87
Found out why the right drive was locked up. My rotating group self destructed. Probably had some help. It never worked right since I got the machine. I was still in the testing phase to see what was wrong with this machine and this happened.
 photo 1304-074056_zps0dc8860b.jpg
F
I have fluid coming from this hole. Is there a seal that may be punctured because of high pressure maybe?
Motordrivehole_zpse06191ea.jpg
 

antfarmer2

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Oct 28, 2013
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Found out why the right drive was locked up. My rotating group self destructed. Probably had some help. It never worked right since I got the machine. I was still in the testing phase to see what was wrong with this machine and this happened.
F
I have fluid coming from this hole. Is there a seal that may be punctured because of high pressure maybe?
You can get the group for $488 at loadersource parts
 

Tazza

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Dec 7, 2004
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Don't know that one
That is possibly case drain, fluid will come out and there shoudl be a seal on the chain case to stop it keeping on going.
With that damage, you need to pull all the lines out and flush the system. Juse one piece left in there will take it out again. Spend the time to flush it out. I use a compressor, diesel and poam pieces. Tear off a little foam, spray with diesel and blow through the line, the foam must exit and takes particles with it, do it a few times to be sure.
Parts are still available, motor and pump parts.
I have never seen that much damage to a pump....
 
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ChandlerW

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Joined
Oct 8, 2013
Messages
87
That is possibly case drain, fluid will come out and there shoudl be a seal on the chain case to stop it keeping on going.
With that damage, you need to pull all the lines out and flush the system. Juse one piece left in there will take it out again. Spend the time to flush it out. I use a compressor, diesel and poam pieces. Tear off a little foam, spray with diesel and blow through the line, the foam must exit and takes particles with it, do it a few times to be sure.
Parts are still available, motor and pump parts.
I have never seen that much damage to a pump....
Oh man, I didn't even think to flush the whole system. I'm glad you suggested it.
I don't think I understand the process though, maybe you can clarify a few things?
Each motor has 2 lines that come out and go to the top of the pump. Lines come out of the pump and go other places.
Will the foam technique go through the pump? Do you think the gearboxes need drained as well?
 

Tazza

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Dec 7, 2004
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16,829
Oh man, I didn't even think to flush the whole system. I'm glad you suggested it.
I don't think I understand the process though, maybe you can clarify a few things?
Each motor has 2 lines that come out and go to the top of the pump. Lines come out of the pump and go other places.
Will the foam technique go through the pump? Do you think the gearboxes need drained as well?
These motors only have 2 lines? the newer style have 3, 2 big ones, one small one.
How long was the machine run after the pump broke? I'd like to see at the very least the entire pump being pulled down and both motors stripped and cleaned. The pieces of foam down the hydraulic lines help push out any particles that may be in there.
When cleaning, you can use petrol/gas to wash the parts then blow down with compressed air. As the fuel dries without residue you can be sure it's clean. Re-assemble with lots of oil.
I'd drain the gearboxes too, just in case something got through the case drain hole. It's a good idea to clean out any goo from the gear wear that may be in there.
 
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ChandlerW

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Joined
Oct 8, 2013
Messages
87
These motors only have 2 lines? the newer style have 3, 2 big ones, one small one.
How long was the machine run after the pump broke? I'd like to see at the very least the entire pump being pulled down and both motors stripped and cleaned. The pieces of foam down the hydraulic lines help push out any particles that may be in there.
When cleaning, you can use petrol/gas to wash the parts then blow down with compressed air. As the fuel dries without residue you can be sure it's clean. Re-assemble with lots of oil.
I'd drain the gearboxes too, just in case something got through the case drain hole. It's a good idea to clean out any goo from the gear wear that may be in there.
Ok, sounds like a plan. I needed to replace the rear main seal on the engine so I may as well do it all at once.
 
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