2018 Toolcat 5600, 2100hours, barely moving forward or backup after a hose break repair

[RichardV-Quebec]

In January (-20C) pushing snow, one of the front right behind the wheel hose broke on the 90 degree iron coupling. All the hydraulic oil ended on the snow. The 5600 stayed there for about one month. I put a screw on hose coupler and changed the other end. Put oil back in and was able to use the machine for about 1 hours then it started to loose moving power either going forward or backward. The front lift and bed hydraulic work fine. It is only the moving part that is the problem. There is a kind of slipping sound coming from the front of the machine. I can get by this (for a short while) by increasing the throttle and it will move more firmly but as it gets warmer, it will loose driving power again even at higher RPM. I changed the hydraulic oil and both filters, opened the filters and there are no debris in them. No luck, same problem. Someone suggested the belt may be loose. I opened the belt cover and the belt is tight and tensionner blocker is very close. There are no warning lights suggesting an error code. Trying to understand this problem, I depress the gas pedal slowing, TC starts moving and when I let go the gas pedal, TC slowly stops as opposed to before (when it was working fine) it would stop immediately. I wonder if this could be a stucked relief valve ? and if so, where would it be? Any ideas anyone ? Thank you.

 

[Interceptor]

The drive system relief valves are in the pump. There is one for forward and one for reverse, so if you are having problems in both directions it's not likely a main relief valve problem unless somehow they both failed at the same time. There is a loop flushing valve in the motor, it allows a small amount of oil to bypass the motor and exit the drive loop to be cooled. This is a spool that shifts when changing direction, so again it's not likely to be the problem. There is a flushing relief valve in the motor, if stuck open it could cause excessive bypass in both directions and could also cause excessive roll out when releasing the pedal. But the orifice in this valve is very small, I wouldn't think it could possibly flow enough to be causing the type of problem you describe.

 

[Xfaxman]

Put oil back in and was able to use the machine for about 1 hours then it started to loose moving power either going forward or backward.

What type of hydraulic oil did you put in it?

 

[RichardV-Quebec]

HD46 Mobil is the oil I just changed with. I am going to make a video of the problem and put it on Youtube for you all to watch. I was expecting metal in the filters when I opened them up but there are no debris of some sort and no milky oil also. Maybe air is in the system but someone said it is a self bleeding system ! unless there is a problem with that process. After the oil change, the ball in the SG is high but the oil level show low ? wonder if the ball is stucked in the high portion ?

 

[RichardV-Quebec]

The drive system relief valves are in the pump. There is one for forward and one for reverse, so if you are having problems in both directions it's not likely a main relief valve problem unless somehow they both failed at the same time. There is a loop flushing valve in the motor, it allows a small amount of oil to bypass the motor and exit the drive loop to be cooled. This is a spool that shifts when changing direction, so again it's not likely to be the problem. There is a flushing relief valve in the motor, if stuck open it could cause excessive bypass in both directions and could also cause excessive roll out when releasing the pedal. But the orifice in this valve is very small, I wouldn't think it could possibly flow enough to be causing the type of problem you describe.

Could it be the shaft moving the swash plate is not working correctly ?

 

[ruffdog]

HD46 Mobil is the oil I just changed with. I am going to make a video of the problem and put it on Youtube for you all to watch. I was expecting metal in the filters when I opened them up but there are no debris of some sort and no milky oil also. Maybe air is in the system but someone said it is a self bleeding system ! unless there is a problem with that process. After the oil change, the ball in the SG is high but the oil level show low ? wonder if the ball is stucked in the high portion ?

It sure looks like the level is low (who knows by how much) and the ball is just stuck to the top. I went out to look at mine with a good light and mirror. Before running it too much, I would want to see the fluid half way up the glass!

 

[Interceptor]

Could it be the shaft moving the swash plate is not working correctly ?

The pump swashplate angle is controlled by a servo which is controlled electronically by the drive controller. There's a swashplate angle sensor, so the controller would know if it's not moving properly in response to input and set a code. There is only one drive pump on the 2007 and newer TC, so a pump problem would affect both front and rear drives equally. The motor swashplates only move when you shift between high and low speed. If you are getting an unusual noise from the front it makes sense that there's an issue with the front drive. I would get all four wheels off the ground and see what's happening with front and rear wheel speeds. The pump flows oil to both motors in parallel, so there can be some variation in wheel speed between front and rear, but with no load they should be very close to the same.

It could also be the brake pressure bleeding off and causing the brakes to apply. This doesn't fit with your description of excessive rollout, but something to consider. The brakes are spring applied, hydraulic release. Check the brake hose for external leaks. Also check gearbox oil level, overfilled gearbox would indicate an internal brake piston leak.

 

[RichardV-Quebec]

The guy who sold me the TC was using AW-32(1st picture) from NAPA and that is what we put in after the hose was temporarely fixed. Last year, we had a leaking bed hose and we added AW-32 also. After the repair(3rd picture), the hose union leaked and I had no more of that oil so I put the trans-30 Oil (see 2nd picture). The 3rd picture shows the repair hose and union. I thought I used HD46 but I was wrong ! Maybe HW30 (2nd picture) is too weak ? The seller gave me a service manual but not for that serial number (mine is AHG815055) so instructions in the manual for gear box oil checking does not match my machine. I ordered the correct manual today and I should get it in 1 week(lol). Could it be the oil is the problem ? I tried filming today the weird sound it makes, trying to move forward. Backward seems to work somehow a bit more but has the same weird sound. Thanks for all the explications so far. It is my understanding the broke hose feeds the front coupler for the lift arm etc...but I could be wrong.

 

[RichardV-Quebec]

Today, for the 1st time, I tried the recording cam, here's the youtube link.

 

[Xfaxman]

Could it be the oil is the problem ?

Yes, that is why I asked what type you put in it.

Many years ago I had a Case 446 garden tractor that acted similar if you used hydraulic oil instead of the motor oil it was designed for.