Bobcat 530 slow on left side.

[Diesellpower]

Hi everyone. I just bought an old bobcat 530. The left side drive is weak, but the machine is still useable. The left side controlls move slower and put noticeably more strain on the engine. To turn, i have to get moving a little and kindof "jerk" it around using the right side. It still has enough power to sink the bucket in a pile of dirt and get a full scoop, but its definately not right.
I have taken apart the drive linkages, machined out all of the pivot points and pressed in brass bushings. The controlls went from really sloppy to about as tight as i think i can expect from this kind of design. The engineering is less then impressive.

Any ideas on where to start troubleshooting from here? I was going to pull the drive motor and re seal it, but the kits are several hundred bucks online. That seems like alot for a handfull of orings.

 

[Diesellpower]

Picture because, why not.

 

[brdgbldr]

It could be the drive motor or the hydrostatic pump.

Here is a video that explains charge pressure and how to test the different parts. The video is not the best production but watching it all the way through will give you a better idea of what it may be and how to narrow it down.

The video is from LOADER PARTS SOURCE. They are a very reputable company and do have more videos on how to test the hydrostatic system. They can also be very helpful over the phone and sell parts and rebuild kits Or they will rebuild for you.

 

[laurencen]

not familiar with this machine but can you switch motors and see if it changes the weak side to the right

 

[Diesellpower]

not familiar with this machine but can you switch motors and see if it changes the weak side to the right

I might just do that if i dont find anything inside the motor that is obviously wrong.
I got into the chain case to remove the problem motor today. The chains on that side are both pretty sloppy. There might be a little bit of side play in the shaft of that motor too. Hard to tell when im elbow deep and tugging against the chains.

Every time i look in a different place, somthing needs new parts. Joys of running equipment thats as old as i am.

 

[laurencen]

some of these machines get abused, my 743 had so much wrong hard to believe it ran to get that much damage, have a s250 with the left rear axle tude ripped out

switching motors will eliminate the motor

 

[Diesellpower]

Well, i was going to tear down and reseal the motors without knowing if one is the problem. But seals are just unavailable. LPS has a kit, but its $400 for what looks like 4 o-rings, a seal and 2 snap rings.

I found an old Ross service manual for the MAE torqmotors, and the individual seal numbers match with TRW and Parker numbers, but they are mostly unavailable anywhere.

Now, im afraid to tear it down and end up turning a motor that is weak into one that doesnt work at all.

I got in a new hydraulic filter and cut apart the old one that has "may 2016" written on it. No glitter at all, which is good news, but there were alot of specs of rubber and 2 chunks of rubber the size of a fingernail clipping.

The chains are just ANSI 60, so instead of paying $186 X 4 from bobcat, i got 20 feet and 4 master links from McMaster Carr for under $200 the 2 i have out already were stretched about 3/8".

Unless anyone has any thoughts on what else to look for, im going to finish the chains and swap motors this weekend to hopefully narrow it down to a pump. At least it looks like Vickers still has some parts available.

 

[River Fluid Power]

View attachment 4605
Picture because, why not.

 

[River Fluid Power]

Do you know if either of the motors have been replaced? If they are newer you would need a different seal kit. The original motors are the can style, with the individual segments enclosed in the "can". You can see the segments on the newer style motors. I can get the kits for you for $225 each if you do end up needing seals for the old can style. They are definitely one of the more overpriced seal kits, mainly due to that style of motor being so old.

 

[Diesellpower]

If they were replaced, it was with the same type. They are both the Ross/TRW MAE2024 that the parts manual calls for.

Its impossible to tell what has been done. Its so old, theres evidence that someone has been in every part of this machine.