RTV 1100 with V4291 Plow Hydraulic Problems

[Ster1]

Hello,
I have an older (2006, I believe) RTV1100 with a plow. It has a double hydraulic pump on the accessory pad on the engine. I'm having some problems with it, and looking for help. Firstly, I'm assuming the front or "main" pump (bigger hose) is for the machine, for the steering and dump. The rear or "aux" pump (smaller hose) is for the plow. I think my problem is with the plow. When I start it up, after 30-40 seconds, I see the hydraulic hose from the aux pump stress, the engine labors and dies and the hose relaxes. I'm thinking the plow is pressuring out and killing the engine. I can't find any documentation about it either. Can anyone help? I can't even keep it running long enough to really do any troubleshooting. Thanks much!

 

[Russell King]

There should be a pressure relief valve on the plow circuit. You really deadhead the pump when you reach the end of movement on the cylinder so then the pressure relief valve opens up and protects the pump.

It sounds like that valve pressure relief is not functioning properly (wherever the plow is positioned), the pump is trying to increase the pressure beyond the capability of the engine, engine stalls and pressure is relieved.

I would disconnect the hose from the pump to the plow control valve inlet port and put the end into a bucket or back into the hydraulic sump and then try to start the engine and see what happens. Don’t run the engine very long or you will pump out all the oil unless the hose is pumping. (I am guessing that the pressure relief valve may be in the control valve)

Report back with your results.

 

[Ster1]

Thank you. For sure the plow is deadheading that circuit. Well, assuming that smaller hose is for the plow. There's a problem with a spool valve or solenoid as well, because the circuit deadheads with no buttons pressed. I assume that the plow is open center. In other words, when no buttons are pressed, all flow returns to the tank. I'm making several assumptions because if my lack of documentation. I'm missing information I was hoping someone here might have. I don't need to disconnect hoses to know something is wrong, I can see it pressurizing when it's not supposed to be.

if I disconnect all those solenoids in the plow, all those spool valves should return to center and there should be no pressure built up. There should be 3, right? For a V blade, there should be 1 for up/down and one for the left V and one for the right V? I'm going to start with that. I wonder if a spool is getting into such a position that the relief isn't seeing the pressure somehow. It does bother me that the relief isn't relieving, but I'll have a look at the spools first.

 

[TheOldHokie]

Thank you. For sure the plow is deadheading that circuit. Well, assuming that smaller hose is for the plow. There's a problem with a spool valve or solenoid as well, because the circuit deadheads with no buttons pressed. I assume that the plow is open center. In other words, when no buttons are pressed, all flow returns to the tank. I'm making several assumptions because if my lack of documentation. I'm missing information I was hoping someone here might have. I don't need to disconnect hoses to know something is wrong, I can see it pressurizing when it's not supposed to be.

if I disconnect all those solenoids in the plow, all those spool valves should return to center and there should be no pressure built up. There should be 3, right? For a V blade, there should be 1 for up/down and one for the left V and one for the right V? I'm going to start with that. I wonder if a spool is getting into such a position that the relief isn't seeing the pressure somehow. It does bother me that the relief isn't relieving, but I'll have a look at the spools first.

To disable the valves Just pull main 12v power to the pushbutton switches. Probably a single (inline) fuse.

If one of the solenoids is stuck the valve may not center when you cut power.

Dan

 

[Ster1]

Right

To disable the valves Just pull main 12v power to the pushbutton switches. Probably a single (inline) fuse.

If one of the solenoids is stuck the valve may not center when you cut power.

Dan

Right! But I need to know which valve is giving me problems. It appears to be the raise / lower function, but I haven't been able to keep it running long enough to text the other functions. Anyway, assuming it's the raise / lower, pulling the plugs one at a time will help identify which valve I need to look at. Hopefully

 

[Ster1]

I just found kubotabooks.com wow somebody put a lot of manuals up there. None for my plow though hah!

 

[TheOldHokie]

I just found kubotabooks.com wow somebody put a lot of manuals up there. None for my plow though hah!

No manuals on Kubotabooks for the plow.

Based on the Messicks parts pages the plow has two double acting cylinders. It should be pretty easy to tell which if any are getting pressure.

Like I said - pulling electrical plugs may not change anything. Pulling the fuse will tell you right up front whether the problem is electrical or mechanical.

Dan

 

[Ster1]

As it turns out, it looks like I was mistaken about... well a few things. Firstly, and possibly most importantly, it wasn't the small hose that was flexing, it was the larger one. For the forward pump. Which, I believe is for the "regular" hydraulic system, not the plow. Which, I believe, just powers the steering and the dump. So, to take the dump out of the equation, I removed the quick disconnects at the rear of the machine, and just ran a hose between the 2 hard lines. No change. The only thing left is the steering. With the engine running, I can turn the steering wheel, which does steer the wheels, but I'm feeling lots of chatter in the steering wheel as I turn it. Massive feedback, if you will. That's where I left it today. I'm going to get back on it on Monday. If I bypass the steering cylinder the same way I bypassed the dump cylinder, and still get that crazy feedback / pressuring out, I might be looking at a bad steering gear or bad relief or both. Of course, the fact it's so small and tightly packed in there is not going to help any.

Thanks all have a good weekend.