kubota loader cylinder threads (ride control)

Smokeydog

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Smokey, did you have a thread somewhere else about your gauge? I remember someone doing something to measure the weight they were lifting.
I dunno how much difference would be between any of these accumulators, but my loader only has one bottle. (~2500#capacity)

Jon, I had a hard time measuring my threads with a pitch gauge, im sure the shop is good enough to tell easily!

I tried using the gauge reading with a weight scale to measure payload. Loads picked with single point with a chain repeatable. Grapple not so much. Any lever arm difference influences the loader pressure.

What the pressure gauge did show was the dynamic pressure spikes from carrying loads were significantly reduced with the soft ride system. Simply a great option.

The hydraulic system is protected on the pump side with relief valves nominally 3000psi. But from the control valves to the cylinders no protection from external forces. So when you lift, curl and push your bucket or grapple into a load the lift pressure can about double confirmed by gauge. That’s why improper back dragging or pulling with grapple lids can damage your equipment with higher than designed operating pressures.
 

rScotty

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I worked at Kubota. JIC fittings.

Just like the zerk threads, there are so many kinds of hydraulic fittings it makes my head spin. There are a bunch of special tapered cones and compressed O rings that industry uses - sometimes - for instrumentation, too.
For identifying zerks, zoro.com sells a thread gauge that Smokeydog found and we both ordered.

I wonder if something similar is available for hydraulic fittings.

rScotty
 
  
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jonsstihl

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The hose fittings are JIC -* i believe but I was talking about the elbow into the female threads of the cylinder port.

I like your setup with the digital gauge. I have a cab so I wasn't thinking of shielding the accumulators and I was looking into piston instead of bladder since the accumulator for empty load will be bottomed out when loaded and I heard bottoming out bladder accumulators should be avoided. But then they are more bulky.

I may just end up getting a comfort ride setup from WR long. For the price its seems to be the most economical solution.
 
  
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jonsstihl

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I think it was discount hydraulic hose that had a great article for identifying different thread types
 

Smokeydog

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I like the digital gauge except cold weather eats batteries. Need to try some lithium aaa. Does have USBc port so maybe could hardwire. Many features over a analog gauge like tare, zero, units, back lighting. It is a 10,000psi gauge. You do need a higher range gauge than what is used for hydraulic testing.

The Kubota soft ride uses two hydraulic bladder accumulators of different precharge pressures. I think dampen over a broad range of loads?

The NOS McCormick soft ride system off eBay, much like the W R Long version, has two accumulators of the same pressure. About 35hp tractor. Watched a utube of a video of WR Long installed on similar sized tractor with one accumulator, valve, hose and tee. Simple system.

The Kubota soft ride system RSCOTTY and I were also a new-old-stock off eBay for a large ag tractor for $200. I installed a 1/2” hard seat needle valve for extra orifice dampening but don’t need it. It did space up the plumbing stack to position the ball valve above the plexiglas shield.
 
  
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jonsstihl

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I was under the impression the WR long system had two different pressures in the bladders to dampen unloaded and loaded but I may have gotten the wrong impression when I was reading. I was definitely going to put a ball valve in the system so I can isolate it if needed.

the precharge pressures are where I think designing the system will get a little tricky. I am planning on starting by hooking up a pressure gauge and seeing what kind of pressure I have loaded and unloaded, then going from there. i read an article somewhere that had a ratio to use of precharge pressure vs system pressure.
 

ptsg

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I was under the impression the WR long system had two different pressures in the bladders to dampen unloaded and loaded but I may have gotten the wrong impression when I was reading. I was definitely going to put a ball valve in the system so I can isolate it if needed.

the precharge pressures are where I think designing the system will get a little tricky. I am planning on starting by hooking up a pressure gauge and seeing what kind of pressure I have loaded and unloaded, then going from there. i read an article somewhere that had a ratio to use of precharge pressure vs system pressure.
Yeah, definitely add the ball valve. There are a lot of situations that you'll benefict from having the soft ride system turned off, like digging into a pile or do delicate work with the forks. With the soft ride on, the forks will all over the place.
 

Smokeydog

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I’m sure the manufacturers use several parameters to select components for their systems. Things in common are they are trying to dampen the dynamic load forces while moving. The smallest SCUT to largest ag tractors operate at about the same pressure but have different flow, pump volume, and cylinder sizes.
Volume displacement also needs to be considered if designing your own system.

Mostly leave it valved in and works seamlessly. Carrying logs, lumber or steel on forks is smoother since terrain bumps are dampened. Carrying anything benefits. Valved out for pallet work or extended boom work. Also valve out when changing ssqa attachments helps. Would mount valve or solenoid control switch conveniently.

If buying a new tractor it would be an option to get.
 
 
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