Kubota U17 auxiliary hydraulic relief valve.

[Ronster]

Does anyone know if the Kubota U17 has a relief valve built into the aux hydraulics? I am looking at a U17 and will want to add a hyd thumb.
Thanks

 

[RickB]

What does the relief valve have to do with adding a thumb? Of course the system has a relief valve. The U17s we have sold have an auxiliary valve in place with hoses and hard lines running along the boom and halfway or more down the dipperstick.

 

[ptsg]

What does the relief valve have to do with adding a thumb? Of course the system has a relief valve. The U17s we have sold have an auxiliary valve in place with hoses and hard lines running along the boom and halfway or more down the dipperstick.

He means a relief valve on the work ports of the auxiliary valve. So when the closing the bucket against the thumb, something gives before breaking stuff.

 

[Ronster]

ptsg, Obrigado. That is exactly what I was asking about. I had heard that without a relief valve on the aux port, you could damage the thumb or worse with the bucket curl.

 

[ptsg]

There was a very recent thread about someone that was going to install a thumb on a Kubota mini ex as well. Can't remember the size of the machine but we were very surprised to see that the auxiliary valve didn't have any provisions for a thumb install (ie: work port relief valves).

 

[Ronster]

I have a Kubota K008 with a mechanical thumb. It does have one power (out) port and a return (tank) port. Hooking up a hyd thumb would have required a diverter valve. The U17 according to the Kubota site, has a two way aux hyd valve.
I think I can get away without a press relief valve if I just apply pressure to whatever I am griping with the thumb and not curl the bucket into the thumb.

 

[Takman]

When I was shopping new machines last year both Kubota dealers told the u17 doesn't have a factory hydraulic thumb option. Sure it's possible though.

 

[RickB]

There are aftermarket options.

 

[Ronster]

I was hoping someone that has a U17 with a thumb would show their set up.

 

[Sodo]

Does anyone know if the Kubota U17 has a relief valve built into the aux hydraulics? I am looking at a U17 and will want to add a hyd thumb.
Thanks

This is a timely post for me, thank you Ronster.
I have a 2006 Kubota KX41 (3800 lbs) similar size to U17 (3700lbs).
It has an aftermarket thumb, which can easily drive the bucket backwards, and it bends the bucket pin.
I think it bends the pin one way when clamping, then bends it the other way when stowing the thumb back against the dipper stick.
I had to let another operator run it and I did not realize he mashed it hard in the stow position often and habitually.
Then the pin broke the first day he used it (I've been using the machine for 300 hours).

He was an extremely experienced operator and any comment on his methods caused him to do it more, and dig slower etc, so to get the job done I had to keep my mouth shut.
I had to weld the pin twice to keep the job moving.
Of course welding a fatigued pin cannot last very long but we finished the job.
His boss came in for the last day so I just jumped on the machine and told them I'm running it from here on out.
I knew the twice-welded pin wasn't gonna survive long.

I have recently replaced the bucket pin with a new unit and now want to reduce the hydraulic pressure to the thumb.

I tried to figure out which of the (many) relief valves was for the aux (thumb) but couldn't identify which one.
Reducing the pressure at the relief adjacent to the aux did not seem to affect the thumb, but the carriage would no longer rotate (prob not the correct relief).

I don't know how similar the valve stack is on our two machines, but I'm very interested.

Ronster can you remove your floorboards and post a pic of your valve stack?