No Drive to front wheels

[pegs11]

I bought a used tool cat with "issues" The issue was... nobody could figure out what was wrong with it.

Not sure of the exact model number. But its a 5600 with a kubota turbo diesel and hi flow hydraulics.

This is the problem its having.

no power/torque/drive to the front wheels.

I drove it up against a stump and stepped on the gas. The back wheels dug in but the front wheels did nothing.

Next I put it up completely off the ground on 4 jack stands and then checked the tire/axel rotation.

With the engine off. The back wheels would counter rotate fairly easily in either direction with just a little effort.

With the engine off The front wheels turn easily independently of each in any direction. They are not connected.

I've read in the forums here the front and rear axels are the same so I'm guessing thats a problem.

Then I started the engine and stepped on the gas pedal. Rear wheels turned as expected and the Right Front tire turned very slowly,

The left didn't rotate at all.

You can actually stop the right wheel and turn it in the opposite direction its trying to turn. So whatever force is trying to rotate it isn't directly connected

After just a couple of minutes I felt the hydraulic lines going to the motor and both felt like they had warm fluid running through them. The port block on the motor was slightly warm too.

There is no noise, no ticks, no grinding, no vibrations, no codes, no leaks, nothing.

So I'm hoping before I start tearing this thing apart someone would be able to narrow it down based upon the information here.

Right now I suspect something is sheared/broken in the gear box since the hydraulics appear to be working and the wheels aren't connected or counter rotating like the back wheels.

Thanks in Advance for any help.

 

[1965tontruck]

I hate to be the bearer of bad news, but the drive motor is bad. The motors run around 1,600-2,000 each. There are two drive motors - one in front and one in rear. Find the serial number plate on right rear and post. The serial number will tell us what model TC you have. Late A and early B models had issues with bad drive motors. There were brass sleeves used in the motors that deteriorated with wear. You can cut the filters apart and look for brass. Again, please post serial number and also search for drive motor failure on this board.

 

[pegs11]

That was my first thought. But after trouble shooting it the symptoms don't sound like a motor to me.

the motor has nothing to do with the limited slip between the left and right wheels.


On this TC if you rotate the right rear wheel forward the left rear wheel rotates in the opposite direction.

But on the front axel if you rotate the right front wheel the left doesn't do anything.

My understanding is that the front and rear axels are the same.

Which would suggest something broken or sheared in the center gear box.
that disconnected the two wheels from each other and from the reduction gearbox off the motor.

But I don't have any parts breakdown to see what it is there and I'm not to crazy about tearing it apart until I hear from someone who has been IN there before.

 

[timm9]

The drive motor issue affected the A series, B series, and C series depending on the build date. All three of my TC's have had drive motor failure and replacement. I would call a dealer and have them run the serial number to see if this unit has already had the drive motors replaced. If so it may not be a drive motor issue. Last season we had something similar with one of our 'B' series TC's. Turned out to be a sheared axle on the drivers side. The driver of that particular unit has been with me for over 10 years and does not have a history of mistreating equipment, in fact just the opposite. We never did figure out how the axle sheared...

 

[pegs11]

This unit was used by a company whose employees are pretty famous for tearing up equipment.

I'm suspecting something like what you are saying. A broken shaft or sheared connection.

Anybody have a parts manual for the axles? and/or gearbox? Something I could study before I take it apart?

 

[SSdoxie]

Here is the parts illustration for the A,B & C series axle. Hope it helps.
One way to make sure it is not the drive motor is take the motor off the rear axle put it on front and see if the front starts truning, before tearing axle apart.

 

[pegs11]

Thanks that parts breakdown helped a lot.

I think I'm going to leave the hyd lines hooked up the motor. Checking statically for connection then put some power to it to see if it spins.

Talked to bobcat tech today to find out if in fact the axels are similar. He said, in general yes.

So if the front axles should be connected internally the same way the back axles are

The fact that you can spin the front wheels independently of each other tells me its probably not the motor, but we will check it just so be sure.

Then I guess we start taking it apart.

I suspect parts breakdown has some parts mislabeled. It lists item 5 p/n 6682083 as a gear and item 4 p/n 6682082 as a axle.

It just appears by the breakdown those two are backwards. So if there is any way for you to check. That would really help.

Anybody ever taken an axle apart on toolcat?

 

[pegs11]

Well, we took the entire axle apart and sure enough.

One of the Axels was sheared completely off.

Aside from what we had already checked, ie, jacking the front end and rotating the wheels. Another quick check would have been to drain the oil out of the gearbox, because there was A LOT of chips in there.

Anyway. Heres some pictures if you are interested

According to Bobcat, there is no history of this happening. Apparently it does though.

There doesn't appear to be any evidence of twisting. Just snapped. Maybe is a very high carbon steel.

 

[timm9]

If according to the Bobcat Dealer this does not 'happen', can I get my $3,700 back?

 

[pegs11]

is that what it cost you?

 

[timm9]

Yes, that was the repair bill but there were unusual circumstances. On my unit it was the rear axle and it was so badly damaged that it would not come out. They had to 'torch' it out in peices which really ran up the labor portion of the bill. That plus paying for over night freight, etc. to get me back up and ruinning as quickly as possible.

 

[pegs11]

We haven't pulled the axle out yet. But its a pretty clean break so we are hoping it will slide out without to much trouble

 

[SSdoxie]

Thanks that parts breakdown helped a lot.

I think I'm going to leave the hyd lines hooked up the motor. Checking statically for connection then put some power to it to see if it spins.

Talked to bobcat tech today to find out if in fact the axels are similar. He said, in general yes.

So if the front axles should be connected internally the same way the back axles are

The fact that you can spin the front wheels independently of each other tells me its probably not the motor, but we will check it just so be sure.

Then I guess we start taking it apart.



I suspect parts breakdown has some parts mislabeled. It lists item 5 p/n 6682083 as a gear and item 4 p/n 6682082 as a axle.

It just appears by the breakdown those two are backwards. So if there is any way for you to check. That would really help.

Anybody ever taken an axle apart on toolcat?

#6682083 is Axle & 662082 is gear.

 

[pegs11]

Well the old shaft came out really easy. The upper an lower hub housing caps/bearings were a bugger. Forget trying to salvage any shims they are PAPER and cost $2.00 a piece. Its not likely you can get the caps off without tearing up the shims anyway.

Just make sure you count how many you have and where they are.

There is also a felt wiper ring on the bottom you should replace. Its cheap and helps keep crap out of the lower bearing race.

It went together pretty easy. But when it was all mounted and running we got some codes that we didn't have before.

These are all 50 series codes. 13 front spd sensor, 14 rear spd sensor 15, is not in my book and 30 which is low power to speed sensors.

We also have no power to the wheel alignment circuit, or no lights.

Never had any codes before we R & Red the axel. And theres no reason the rear spd should have any codes.

The spd senors and the alignment circuit share a common power source. But for right now, the numbers are so small in my book I can't read the wire numbers and connector locations even with a magnifying glass.

 

[pegs11]

Here is the parts illustration for the A,B & C series axle. Hope it helps.
One way to make sure it is not the drive motor is take the motor off the rear axle put it on front and see if the front starts truning, before tearing axle apart.

Doxie any chance of getting a pdf of pages 389 - 391 from the maintenance manual?

I have a copy but apparently some of the numbers were to small for the printer to print so they don't even look like numbers.

I'f chased down the common power wire that the spd sensors and the wheel alignment system use. And I'm trying to follow that back to the source to see where the problem is. But just can't read the connector numbers or the wire numbers.

Any help would be great Thx

 

[SSdoxie]

Doxie any chance of getting a pdf of pages 389 - 391 from the maintenance manual?

I have a copy but apparently some of the numbers were to small for the printer to print so they don't even look like numbers.

I'f chased down the common power wire that the spd sensors and the wheel alignment system use. And I'm trying to follow that back to the source to see where the problem is. But just can't read the connector numbers or the wire numbers.

Any help would be great Thx

What is the first 4 numbers/letters of your serial number? Just to make sure I locate the correct page information.

 

[pegs11]

424711677

Thx

Do you have any documentation on the computer?

It looked like the schematic showed there was a common power wire for the wheel alignment and wheel sensor power but I couldn't see where it went past a multi-pin connector. Which I'm guessing is the computer

Thx again

 

[SSdoxie]

pegs11,
Attached is the wire schematics. You are correct wheel speed and position sensors are fed by same supply, 5 volt from the controller. You could test for 5 volts at controller pin #30 wire #1530.
I didn't go back to look to see which axle you had to replace but was there a wheel position sensor on that hub? I'm not positive on this but I think it is possible to put those sensors in 180 degrees out and if so, it might be so far out of range causing all the voltage in the circuit is dumped through that sensor the rest would not be able to send strong enough signal back to controller. If there was a sensor in the top bearing cap on that hub take it out and ty turning the pin 180.

More thinking as I go here than true diagnostics but trying to find some common ground with having these codes after the repair and no history of it prior.
The 50-15 code was added later. It is just to confirm more than 1 sensor with same code error.

 

[pegs11]

The wheel sensor was on the opposite hub. The only thing we did was to disconnect the harness inside the hydraulic ram tunnel.

There was one other thing we did that I will check and that was to reattach the wiring sheathing for the position sensor wiring with a hose clamp.

There was about 3" of millivolt/light wiring exposed so we slid the sheathing over it and held it in place with a hose clamp to protect the wiring.

I think I'll check for power on the #30 pin like you suggested. That will tell us a lot.

Since I'm really expecting there to be no power at that pin. What then? Is it possible it got shorted out some how? Is there a fuse or something that can be reset or replaced? Seems odd that wiring circuit wouldn't have some kind of short/overload protection.

Thanks for the pdf. I could see right away that was pin 30 and not 80 LOL.

 

[SSdoxie]

Make sure the pins got lined up and pushed together tight were unplugged it. One of the 5 volt wires may have pushed back in the plug when you reconnected it.
Circuit protection for the 5 volt is internal in the controller.