B21 hydraulic pressure setting and test fitting

[joea99]

Want to check hydraulic pressure on B21. The WSM make is seem pretty simple, though tedious, with a screw and lock nut adjustment, no shims. That's a plus.

Don't have a test kit, but was looking at the bxpanded kit. I'm waiting for some response from them on questions.

One being, would it include the "adapter 58" the WSM calls out to connect the gauge to the port? Kind of pricey as a stand alone purchase, and would push me to just making up my own.

Anyone done it, or know that a suitable "adapter" is? Too old and fragile to got out in the chill today and play.

 

[bdhsfz6]

I'm not sure what this test kit includes or what it cost but if you have rear remotes, you can make your own test gauge. Get a cheap 3000 psi hyd. gauge, short hyd whip hose and a pioneer connector at Tractor Supply. You can read the pressure by connecting the rig to a rear remote.

I built one years ago and have been using it on my B, L and MX series Kubotas.

 

[joea99]

I'm not sure what this test kit includes or what it cost but if you have rear remotes, you can make your own test gauge. Get a cheap 3000 psi hyd. gauge, short hyd whip hose and a pioneer connector at Tractor Supply. You can read the pressure by connecting the rig to a rear remote.

I built one years ago and have been using it on my B, L and MX series Kubotas.

I do have PB to the backhoe, so I guess I could find a quick coupler to match the supply and use that. Saves me taking a chance that I have deciphered "PT 1/4" properly as BSPT 1/4 for the "Adapter 58" they call out. Won't have to bother with an adapter. Doubt the pressure can be much different at any point in the circuit as long as nothing is moving.

Do you find the pressure need to be checked and adjusted often?

 

[Smokeydog]

Be careful. Not sure if the hydraulic supply to bh open center system has a relief. The reliefs are on the hoe controls. I once failed to reconnect the supply line when removing the bh on my B20 and when I started the engine it went full load and bursted the supply line hose in seconds.

Have a mounted 10,000psi gauge plumbed into the loader lift circuit on the M59. I think you could check any cylinder circuit for max pressure easily with some jic fittings.

Think the bx expanded gauge uses the QDs on a bx removable loader to plumb in the gauge. The B21 loader doesn’t dismount or have QDs.

 

[bdhsfz6]

I do have PB to the backhoe, so I guess I could find a quick coupler to match the supply and use that. Saves me taking a chance that I have deciphered "PT 1/4" properly as BSPT 1/4 for the "Adapter 58" they call out. Won't have to bother with an adapter. Doubt the pressure can be much different at any point in the circuit as long as nothing is moving.

Do you find the pressure need to be checked and adjusted often?

I wouldn't use the rig I mentioned unless you have a rear remote or a removable FEL hydraulic coupler. Using the BH hydraulic circuit is a bad idea for the reason smokeydog mentioned above.

A couple of the tractors I've bought had the hydraulic pressure set 5 - 10% lower than spec and I've had to correct it. The dealer claims it's for safety reasons. Once set, I've never had to re adjust it.

 

[joea99]

Hmm. I can take a look at the hydraulic circuit again. But I recall the relief being in a "hydraulic block" that is under the seat, over the oil tank and plumbed in to the tractor circuit regardless if the BH was on or off+, so it protects the entire system. The adjustment is done right in that area with a screw and lock nut. From what I read, most use shims.+

Anyway the WSM does describe how to do it, but it requires unbolting some stuff, removing a plug, inserting an adapter (BSP I guess) and the hose and gauge to that. I just never like messing with "plug taper" fitting if I don't have to.

I have plenty of time to mull this over

 

[Downeaster2024]

I'm not sure what this test kit includes or what it cost but if you have rear remotes, you can make your own test gauge. Get a cheap 3000 psi hyd. gauge, short hyd whip hose and a pioneer connector at Tractor Supply. You can read the pressure by connecting the rig to a rear remote.

I built one years ago and have been using it on my B, L and MX series Kubotas.

I bought a pressure valve up to 3000lbs for less than $10 dollars, and a hydraulic female for $20. Thing works great for less than $30. You don't necessarily need shims, just some flat washers that are the same size as the spring. Start with the thinnest washer, place it in first then the thin spacer that was alread in. and work up to the pressure you want.

 

[bdhsfz6]

I bought a pressure valve up to 3000lbs for less than $10 dollars, and a hydraulic female for $20. Thing works great for less than $30. You don't necessarily need shims, just some flat washers that are the same size as the spring. Start with the thinnest washer, place it in first then the thin spacer that was alread in. and work up to the pressure you want.

Sometimes, flat washers are too thick, and raise the pressure too much.

A quick and easy method to thin them is to put the washer on a piece of wood and strike it with a hammer. Then, using the block of wood as a handle, sand or grind the imbedded washer down to the thickness you want.

 

[joea99]

I never did get around to this. But, as far as the pressure gauge hookup goes, I think it would be OK top rig up a gauge to a T fitting with an appropriate QC fitting at each end, disconnect the supply to the BH/remote and plug the gauge fixture in the in between.

That way I could get an idea of how pressure is acting while in use as well.

Sane?

Interesting info on the shims, but the B21 has a screw/locknut adjustment.