Resealing valve for front end loader controls

[rangerfredbob]

My Kubota has a generic aftermarket loader most likely from the 80's if I had to guess and the bucket drops fast (about 6" height in 2-3 minutes when the fluid is warm, faster at slower engine speeds for whatever reason, tilt droops too but less load so slower) and one of the valves is leaking out of the part that slides in and out (shuttle?).

Anywho, I imagine most of the loader problems are related to the sealing of the valve, what's likely involved? Is it just going to be O rings in there that are shot since they're 30 years old? I looked and don't see any identification marks on the valves, it's a 4 piece thing, end caps that have the inlet and outlet fittings and the two stages for the lift and tilt and two bolts going all the way through all 4 pieces.

Not leaking enough to have to add fluid but it's making a mess and the drooping bucket is getting old...

 

[mrmikey]

Unless it's an external leak you may be out of luck. Usually the spools are lapped with the body and there's no seals...........M
**EDIT** I see it is an external leak, probably not an 'O' ring but a quad ring.

 

[Zebrafive]

The valve on my JD 245 loader (probably 40+ years old) was leaking, but not affecting operation. It has o rings at each end of each spool.
You need to determine valve maker and try and find parts diagram. Or just take it apart and see if it has o rings, then try and match up new ones if it does.


If the spools or spool bores are worn you will need to replace the valve.

 

[rangerfredbob]

Sounds like the bores are leaking internally as well as the external leak, any reasonable aftermarket valves for low flow (the side mount pump is probably 2000psi max and I'd guess 5-7gpm max) two position control with 1/4" NPT outlet ports and I think 3/8" NPT supply/return ports. I don't know the best way to look things up, and haven't tried very hard yet.

 

[RNeumann]

Loader Valves - LVS LVT LVR

 

[Dave M7040]

You need to take the time to go thru the attached cylinder test procedure. Rarely it is the valve!

Even leaks from the valve's external features like float detent, do not account for dropping loader arms and buckets..

If you determine the loader valve needs replacing, do not make the mistake of going with a flow rating bigger/higher than your system's performance which is likely around 4 gpm unless you have an external pump just for the loader.

The result of too big a flow rating is a loader with no fine control. Better too small than too big.

Dave M7040

 

[rangerfredbob]

It does have an external pump just for the loader with a single V belt shared with the water pump and generator on a hokey bracket... about 1-1.5 gallon tank (haven't done the math) on the side.

Those are reasonable tests and will try to get to it.

The valve on it does not have a float detent, it's just a generic two way valve.

Thanks.

 

[rangerfredbob]

Thinking more I don't think I want to screw with the old warn out valve, the lever linkages are so worn out they can cross...

Right now the belt for the pump and so forth up front is gone so I'm going to replace that in a little bit but the valve is leaking way worse now... looking at valves I've come up with a few that look built way better than whatever Kwik Way used in the '80's when they put the loader on... Going to SAE fittings from pipe thread doesn't scare me, we have accounts with hose suppliers and Napa at work...

https://www.amazon.com/BAILEY-INTER...=loader+valve&qid=1565961083&s=gateway&sr=8-8

https://www.amazon.com/Hydraulic-Di...=loader+valve&qid=1566005819&s=gateway&sr=8-4

https://www.amazon.com/NorTrac-Mono...loader+valve&qid=1566005819&s=gateway&sr=8-16

https://www.amazon.com/Mophorn-Hydr...loader+valve&qid=1566005819&s=gateway&sr=8-13

https://www.amazon.com/Mophorn-Hydr...loader+valve&qid=1566005819&s=gateway&sr=8-10

Sorry, didn't have it in me to make fancy links. There's a couple two lever, one three lever three way valve (could come in handy) and one one lever two way valve... The current valve isn't anything special, it's just bolted down with 2-4 bolts to a plate that is held to the loader with one bolt, easy to modify to make any of the above fit.

 

[Zebrafive]

Getting away from NPT to SAE (ORB) is a good thing!

 

[rangerfredbob]

I really wish there were labels on the pump or valve... I'm pretty sure getting a valve that is rated around 10gpm would be reasonable, maybe I'll get a picture of the pump and valve today and see if anyone can guestimate a reasonable flow rate... since I'll be into the valve changing a hose later today that blew in my face yesterday... it was for the bucket tilt and didn't stop squirting until the tractor was shut down so the valve has to be leaking internally.