Toolcat drive issue

[snmirab]

Well scratch the "It's Fixed" post. It worked great the day I got it back and two nights ago, though all I did was a test drive a couple hundred feet. This morning with snow on the ground ready to be cleared, it acted up identically to the first time. I am pretty confident that it is temperature related. When I dropped it off and even up till last night, it stayed at temps 40 degrees and plus, this morning it was 29 and the problem was right back. Called Bobcat, they are going to research and see what they can find... It started off intermittent, then became sustained. As I was driving and draging the back axle, I checked for codes 'none' came up...

As far as the breaks go, I have been told the same this by bobcat, that they last VERY long and are hydraulicly applied. I have read some previous threads that the pads " crumbled" and had to be replaced. I don;t think they drag at low speeds becasue I have noticed that if I am on an incline, say a ramp for a trailer, if I just touch the accelerator, the machine will actuall "drift" back until give it more pedal and it builds up ample power to propel forward. From what i can tell, it is a pump pressure issue, because when I swap the pressure controller wires from front to back pumps, the problem swaps to the front axle, so the pump and axle are responding with proper inputs... I might swap the speed sensors from front to back and see what effect that has... Tech saw the axle birping gear oil out of the breather and pointed at that, but I don;t see an issue there, but i'll double check that aswell...
I hate paying for a tech's learning curve at the dealer...

 

[snmirab]

I have not gotten a chance to get it back to the bobcat dealer. Had it out this past weekend and it did the same thing, with air temp at 40. So I let it run for about 1/2 hour and everything ran fine after it warmed up... so it sounds alot like what pairiefencer described with him machine.


pairiefencer, did you ever get your problem resolved? if so, what was discovered?

 

[pairiefencer]

I have not gotten a chance to get it back to the bobcat dealer. Had it out this past weekend and it did the same thing, with air temp at 40. So I let it run for about 1/2 hour and everything ran fine after it warmed up... so it sounds alot like what pairiefencer described with him machine.


pairiefencer, did you ever get your problem resolved? if so, what was discovered?

Just for everybodies info I will post my results. It wasn't the brake issue that the dealer thought. Cost over $1000 and same problem. They then unplugged the rear speed sensor and it works fine except that I get an error message. They claim it will work fine with the speed sensor unplugged. I haven't been driving it much lately since it hasn't snowed. The speed sensor costs over $300. Sounds like snmirab has tried all this already so maybe his problem is more related to hydraulic pressure? This is only the second time I have had work done at this dealer and I have gotten the shaft both times. They said they guarantee their work but I guess that doesn't mean much. Most other mechanics won't touch them because Bobcat doesn't let out their computer programs. Sorry I couldn't be of more help.

 

[snmirab]

It's 29 degrees out and I just started up the TC to duplicate the issue with the rear diff not driving. As planned, it drug it's wheels with only the front driving. Disconnected the rear speed sensor and after ignoring the code fault and lack of speed display, the TC drove normally, plugged it back in and the problem came right back... The rear diff is burping oil and it is caked over the speed sensor, maybe that is the cause, but i am convinced it is the speed sensor now...

I am glad that I posted this board. I owe you a drink praire, thank you very much for you help.

In another unrelated issue, my diff lock was not engaging, after reading other threads and someone suggest it only works in two wheel steering, so I switch it over, and worked like a champ!

 

[rayden25]

Guys try to keep in mind that this is a very complicated machine and there are highly trained individuals designing and supporting this product. You guys are completely off base on how the brakes work. The brakes are only there for parking and they are spring applied and pressure released. The rear speed sensor has been taken out of the software for about a year now. If you have had the software updated within the last year the rear speed sensor is not used anymore. Trust the people at the dealers, they know far more about this product than you may think, additionally they have a direct line to the factory for troubleshooting these problems.

 

[J_J]

You never did say which model you had, a C or D 5600 The bolts are used on the C model. I did find out that there is no good way to tow a disabled D model.

 

[DEWFPO]

Trust the people at the dealers, they know far more about this product than you may think, additionally they have a direct line to the factory for troubleshooting these problems.

That's a broad statement and kinda tough. Everyone needs to scope that out themselves with their local service provider. When I talked to the Service Manager at the dealership a few weeks ago, he didn't know there was a different procedure to be used when towing a "D" Model. The "D"'s have been out for a while now and this guy had quit a bit of experience. He also does a significant portion of the field service work himself (he's been to my place twice to work on my machine).

DEWFPO

 

[J_J]

That's a broad statement and kinda tough. Everyone needs to scope that out themselves with their local service provider. When I talked to the Service Manager at the dealership a few weeks ago, he didn't know there was a different procedure to be used when towing a "D" Model. The "D"'s have been out for a while now and this guy had quit a bit of experience.

DEWFPO

I totally agree. The service manager gave me erroneous data. I don't think everyone of the mechanics go to school on all the new products. It probably works like this. One day, a new model arrives to the dealership with manuals, maybe not. Then someone will learn by doing, and then tell other mechanics about the system. It may be a CD training course that they take home and learn as much as they can before the new TC they just sold comes back in for something or another. Learning is easy, retention is a bit** as you get older.

 

[J_J]

Guys try to keep in mind that this is a very complicated machine and there are highly trained individuals designing and supporting this product. You guys are completely off base on how the brakes work. The brakes are only there for parking and they are spring applied and pressure released. The rear speed sensor has been taken out of the software for about a year now. If you have had the software updated within the last year the rear speed sensor is not used anymore. Trust the people at the dealers, they know far more about this product than you may think, additionally they have a direct line to the factory for troubleshooting these problems.

We know the hydraulic motors have internal brakes, but do you have to apply them, or, or they applied when the hydraulic pressure goes below the spring pressure. Now are these springs manually activated, such as pulling a parking brake lever, or they automatic, such as when the hydraulic motors are at rest. Some where I remember about the brakes are released when the motor hydraulic pressure goes above 600 psi, so that means that between 0 psi and 600 psi, the brakes are on to some degree, and the brake force is usually stated in the specs for the motor.

And NO, I am not way off base, maybe a little, and I bet I could learn your system if I had a new TC-5600, or 5610.

 

[DEWFPO]

We know the hydraulic motors have internal brakes, but do you have to apply them, or, or they applied when the hydraulic pressure goes below the spring pressure. Now are these springs manually activated, such as pulling a parking brake lever, or they automatic, such as when the hydraulic motors are at rest. Some where I remember about the brakes are released when the motor hydraulic pressure goes above 600 psi, so that means that between 0 psi and 600 psi, the brakes are on to some degree, and the brake force is usually stated in the specs for the motor.

And NO, I am not way off base, maybe a little, and I bet I could learn your system if I had a new TC-5600, or 5610.

At slow speeds in Work Mode with less than max. engine rpm (~1900) I can heard the brakes squealing as I'm moving around even at several mph with the bucket on so I guess there's not enough residual pressure to completely release the brakes. Just sounds weird like I'm dragging the brakes. Makes me think I'm wearing them out fast.

The mechanic/Service Manager said it takes about 300-400 psi to release the brakes but I think was a guess based on some experience. I've never actually used my brake pedal to stop the Toolcat, only to keep it from moving again when stopped on a steep hill. It will start to move once stopped on a steep slope.

I'm not sure what actually happens when the brake pedal is pushed.

DEWFPO