ASV RC100 Won't turn when hot.

[Opie495]

I just bought a used RC100 with an unknown amount of hours as the display seems inoperative. But that isn't my issue. When cold the RC100 acts mostly as it should although turning is jerky and fast sometimes and slow others. However, when warmed up you pretty much have to stop moving to turn either direction. It does turn better left than right. I have not done any trouble shooting as I am attempting to source a manual for the machine.

Here is what I do know:
1. The lift and bucket hydraulics work great, pump seems strong and will lift the machine.
2. The drive hydraulics, I guess the pump and drive motors, seem strong when going forward as it will load the bucket with topsoil or virgin soil. However, it will only move and/or scoop dirt at full throttle.
3. While moving forward, noted above, it won't turn and will, in fact, slow and stop if you keep trying to turn while moving.
4. When stopped and at full throttle the machine will spin in place, either direction.
4. In reverse the machine moves like it should but again at full throttle.

Based on the above you can see I can use the machine. I have to run wide open, stop and aim where I want to go, move and periodically stop and aim again to reach my intended target. Ugh, frustrating.

I don't have a manual so I don't know all the steps to troubleshoot but my way of thinking is the point of hydraulic distribution is possibly dirty or has partial blockage.

Any thoughts?

Thanks in advance for any input.

 

[Hay Dude]

Is hydraulic fluid level ok? Start with simple stuff. Is there a pump screen?
The last time I replaced a pump, the hydraulics were only intermittently working, then it quit altogether.

 

[oldnslo]

With a skid steer you have two hydrostatic pumps and two track drive motors that operate as two separate systems.

Hopefully ASV installed some test ports on those drives so that you can check the following:
1) if you can access the pumps and wheel motors drive it for a few minutes and check the temperature of the housing or cases on each pump and motor. If one of them is significantly hotter than the others that would point towards that component is failing.
1a) Charge pressure; does it vary significantly from idle to full throttle and from cold to running temperature? Loss of charge pressure will make system operate erratically. I do not know what the pressure should be.



Since you need full throttle I would suspect a faulty component causing loss of charge pressure or pilot control pressure but that is just a semi-educated guess without additional information.

In looking at parts diagrams on-line it appears that the RC100 has hydraulic pilot joy sticks so would check pilot pressure at the joy stick. Again not sure what this pressure should be. Frequently charge flow is used for pilot pressure but it maybe lower for pilot controls.

Hopefully this information provides a starting point for you.

 

[Opie495]

Is hydraulic fluid level ok? Start with simple stuff. Is there a pump screen?
The last time I replaced a pump, the hydraulics were only intermittently working, then it quit altogether.

Thanks for that info, I'm going over the whole machine whenever it quits raining, ugh, but then there are the holidays. I bought a complete set of filters for the machine and have already done the oil and two air filters. Hydraulics are next. But with no manual can you tell me where the screen is you are talking about?

 

[Opie495]

With a skid steer you have two hydrostatic pumps and two track drive motors that operate as two separate systems.

Hopefully ASV installed some test ports on those drives so that you can check the following:
1) if you can access the pumps and wheel motors drive it for a few minutes and check the temperature of the housing or cases on each pump and motor. If one of them is significantly hotter than the others that would point towards that component is failing.
1a) Charge pressure; does it vary significantly from idle to full throttle and from cold to running temperature? Loss of charge pressure will make system operate erratically. I do not know what the pressure should be.



Since you need full throttle I would suspect a faulty component causing loss of charge pressure or pilot control pressure but that is just a semi-educated guess without additional information.

In looking at parts diagrams on-line it appears that the RC100 has hydraulic pilot joy sticks so would check pilot pressure at the joy stick. Again not sure what this pressure should be. Frequently charge flow is used for pilot pressure but it maybe lower for pilot controls.

Hopefully this information provides a starting point for you.

That is great info and yes, it does give me a starting point. Waiting on sourcing a manual and that should help with pressures, etc.

 

[agjones]

That screen is an intake filter, asv terex is known for it getting blocked up. On my little 30, it was in the bottom of the hydraulic tank, you probably have two covered accesses to the tank, it's most likely at the bottom of one.

The pilot pressure is usually around 500psi.

Only happening when hot though... That's probably a seal or swash plate allowing the thinner fluid to escape.

 

[Opie495]

Caught up in the holidays and now I have a bit of a hose leak. Jumping on both issues right after New Years. I really want to explore the screen business, sounds like something that if not the total cause may have at least added to it.

PS: Hydraulic tank is now empty so I will be easier, I assume, to pull that fitting and check the screen.

 

[agjones]

We wore through a drive hose on our asv-terex too. Rubs at the frame. Doubled down on protection no problems since. Good luck

 

[Opie495]

My drive hoses have some type of sleeve they thread thru so hopefully that is the extra protection. Not sure if it is one of those hoses that is leaking. I will trouble shoot just after 01/01.. Thanks for the info!

 

[agjones]

You bet, mine weren't right through that nylon. I added the bendable plastic guards you zip tie. 1500h ago....