259d travel problems

[Craig Skaggs]

Firs time poster, after researching my can off everywhere, there seems to be a ton of experience on this site.

Long story short, there has been an addition of a new piece of equipment that I do not know the history of. It is a 259d Caterpillar skid steer(~2500 hours) with travel problems. My brother actually purchased this skid steer knowing it had issues and I ended up with it in my shop. It will travel in forward and reverse very slowly but if you pick up speed it will throw an error code of E569-2 "Unexpected left motor reverse speed detected". When it first arrived at my shop this was the condition it was in and upon further inspection I found the right final drive was extremely low on oil and was growling and vibrating when trying to move the machine. I did find metal in the oil and made the decision to change the final drive with a new unit from finaldrivemotors.com. The other final drive was full of oil and no metal particles were found.

After changing the final drive I ran the machine for a small amount of time to get the hydraulic oil circulating to change the filter, one because it needed it and another symptom it had was the hydraulic oil was getting hot and alarming. Hoping the final drive was causing both issues, after pulling the filter and inspecting it by cutting it apart and squeezing the oil out I found no metal particles! After the hydraulic oil change I scanned the radiator with a flir thermal imaging camera and found the radiator was doing an excellent job of exchanging heat and found nothing getting too hot. It doesn't seem to get hot just sitting and running you have to be driving to get the hydraulic fluid to an alarming temperature.

My mind is going to the final drive "brakes" are not unlocking, I read where there is a charge circuit that will need pressure before they will release but I do not know how/where to check that. Also when it throws the error code it mentions the speed sensor and associated wiring. I did do a continuity test of both speed sensors and found a discrepancy between the two, although it is minor it would be nice to know what the resistance should be between the pins.

I switched the wiring from left to right on the speed sensors as well and it actually threw a different code after that but did go to the right side. The code was: Right drive motor speed sensor #2 abnormal frequency, pulse width or period,

Any help would be appreciated!

 

[Nige]

G'day & welcome.

First up let me see if I can get your thread moved to the CTL/MTL section where it belongs. This section is for "full fat" track loaders not something as small as yours. No worries, you weren't to know.

Second up, please post a Serial Number. It helps in finding technical information.

My first suggestion based on the information that you posted above is to remove both speed sensors (they are held in place with a single Allen screw) and clean the nose ends of both of them. See what that does. If no change swap the sensors side to side (LH to RH & vice versa) and see what happens.

Also if you have the information please post details of the Codes you got. I guess it will be something like 2687-8.

 

[Craig Skaggs]

Thanks for correcting my rookie mistake Nige!

CAT0259DHFTL12784

It will be the weekend before I get the chance to swap those sensors around but in the meantime there is the code details below.

The code that I have received before changing the final drive were:
E569-2 Unexpected left motor reverse speed detected check the motor speed sensor and wiring

The code that I received after changing the final drive and making sure the speed sensor was clean were:
E569-2 Unexpected left motor reverse speed detected check the motor speed sensor and wiring

I then swapped sides of the harness and got codes:
2688-8 Right Drive motor speed sensor #2 abnormal frequency, pulse width or period
E568-2 Unexpected left motor forward speed detected check the motor speed sensor and wiring
I missed getting a picture of the last code but it would only allow the machine to drive in a "creep" or "limp" mode. If I see it again I will put it in the thread.

Thanks for your help.

 

[Craig Skaggs]

So after a ton of research and trouble shooting I really think someone has monkeyed with the hose location to one or both of the final drives. I have looked through the hydraulic schematic but as far as hose location to actual/physical location I am having a tough time figuring out what should go where. I have a this picture I wonder if someone on this forum could look at a 259D at their disposal and tell me where 1, 2 and 3 go on the R and L final drives? I have looked at the local dealership and they don't have one on the lot.

Any help is definitely appreciated!

 

[Craig Skaggs]

Update on this 259d: 3 of the 4 hoses were in the wrong location! Once they were all installed in the correct position the tracks respond as they should. Unfortunately the right side turns at approximately 50% slower than the left, this is noticed visually and on the operators diagnostic screen. The right side has a brand new final drive on it. I did switch sides with the speed sensors and the problem remained the same. Could the charge circuit not be releasing the brake resulting in a slower speed or is it just a spool that is stuck? Any help is always appreciated!

 

[Nige]

As a first step drain the oil from the right side final drive and look for sparklies in what comes out. The finals take about 1 quart of synthetic 85W/140 gear oil. The oil should be changed every time you change the engine oil.

 

[Craig Skaggs]

This is the side with the brand new final drive, when I pulled the speed sensor out it did have a small metal particle on it. I put a magnet in and found a couple more small particles. In my mind this side of the final drive is only hydraulic components and the side with the gear oil is separate. Just making sure we are on the same page.
I have performed the hydraulic fluid filter inspection as you have described in other posts and it is clean but I have to imagine there is some metal floating around in this part of the circuit from the last final drive. I assume I should have taken other precautions when I changed it but when I found the filter clean so I figured I was good to go...

 

[Nige]

Yes. I was interested in the condition of the planetary gear side, not the motor. Any debris from the motor will end up in the hydraulic system filter.

I assume I should have taken other precautions when I changed it but when I found the filter clean so It figured I was good to go...

So you installed the replacement final drive yourself.? It was an aftermarket unit IIRC.? Was it sold to you as an equiavlent of a particular OEM Cat Part Number.?

 

[Craig Skaggs]

Yes the replacement drive was sold as an equivalent unit, I called them as I suspected the gear ratio was different from the original. They said they were the same and they didn't sell a different gear ratio for this unit. They did say speed sensors have been a large problem with this unit but it turns out it doesn't look like the issue this time. It is a two speed machine and I wonder if the right side is just not getting the signal (hydraulically) that it is supposed to be in the second speed? I didn't try it in creep mode, if they both went the same speed in creep I guess that would tell me.

 

[Nige]

I didn't try it in creep mode, if they both went the same speed in creep I guess that would tell me.

That would be a good next step.

 

[Erasmoemo3]

Yes the replacement drive was sold as an equivalent unit, I called them as I suspected the gear ratio was different from the original. They said they were the same and they didn't sell a different gear ratio for this unit. They did say speed sensors have been a large problem with this unit but it turns out it doesn't look like the issue this time. It is a two speed machine and I wonder if the right side is just not getting the signal (hydraulically) that it is supposed to be in the second speed? I didn't try it in creep mode, if they both went the same speed in creep I guess that would tell me.

Were u able to get it fixed ?