Front End Loader Pressure check

[Piston]

Thanks,
sounds easy enough...

 

[Piston]

will this gauge work?
Surplus Center - 3000 PSI 4 1/2 LM DRY GAUGE

 

[J_J]

I would recommend this liquid filled gage instead, as some dampening is good.

https://www.surpluscenter.com/item.asp?item=21-1044&catname=hydraulic

 

[dex3361]

I would recommend this liquid filled gage instead, as some dampening is good.

https://www.surpluscenter.com/item.asp?item=21-1044&catname=hydraulic

I agree that a liquid filled gauge would be better. The liquid dampens out the pressure spikes so you get a stable reading.

 

[Chilly807]

Here's a quick of video of checking mine..

YouTube - ‪L3400 loader pressure test‬‏

I simply removed the male quick connect from the loader hose, screwed the gauge into it, and re-connected to the female QC on the loader valve. Move the lever (for that particular hose) and the results are pretty plain. The gauge isn't liquid filled, but didn't bounce too badly at all.

Sean

 

[J_J]

Liquid-filled gauge resists vibration and lasts longer

 

[Chilly807]

Liquid-filled gauge resists vibration and lasts longer

I agree, but when you already have a non-liquid one handy..

Sean

 

[Piston]

I would recommend this liquid filled gage instead, as some dampening is good.

https://www.surpluscenter.com/item.asp?item=21-1044&catname=hydraulic

THanks, I'll order that one, it's cheaper too :thumbsup:
I'll also order the quick disconnect for the gauge.

 

[KubotaNewb]

So following Dex3361 (Randall) and JJ's advice, I ordered my liquid filled gauge and other parts (shims, qd) needed and tested my L4400. I was at 2430 and decided to add a shim. I added a 0.4 (31351-37950 (kubota PN)) and it raised my psi 230. So I had to take it out and add a 0.1 (31351-37970 (kubota PN)) and a 0.2 (31351-37960 (kubota PN)) and got my pressure to 2600. I tested the front end loader and in the dry dirt it had more lift but in the thick mud felt the same where I had to back out some to get the lift. Dex's idea of the vaccum with the fluid worked perfect. The part number for the female quick disconnect from Kubota for the L4400 LA703/LA703A is 7J417-66320. Thanks once again to Randall and JJ.

 

[5030]

keep in mind one important constant and that is, increasing the pressure also increases the chance of blowing a packing or rod seal and both are expensive to replace both in time removing the cylinder and replacing the parts.

 

[dex3361]

keep in mind one important constant and that is, increasing the pressure also increases the chance of blowing a packing or rod seal and both are expensive to replace both in time removing the cylinder and replacing the parts.

Those are the specification pressures on the loader. I feel the same way about going over the design pressure, its just not worth the risk. Besides there have been a few times that I have had a rear wheel off of the ground with my weight box full while using the FEL. Good warning though.:thumbsup:

 

[5030]

I've considered plumbing in a pressure gage (liquid filled) in the hydraulic line on tractors I've owned and do own (I have a few laying around in the shop, gages I mean...lol) but I never have. If the FEL lofts the rear end, the pump is making enough pressure for my needs.

Both my M9 and my 105 can get rear light with the FEL's loaded down and both have cast weights on the rears. Good enough for me.

The 105 will dead lift a Chevy 3/4 ton pickup and the M9 will lift one high enough to drag sideways. Been there, did that to my neighbors truck.

I'm more into flow volume than actual delivered pressure anyway.

 

[Chilly807]

I'd be more concerned about bending either the loader or the front axle. Hydraulic cylinders rated at 3000 psi are usually good to at least twice that pressure for safety standards.

I can pick a rear wheel clear of the ground with the LA463 loader on the L3400 I have if a bucket corner is hooked under a root for example. It won't quite lift both clear, but it comes close.

Sean

 

[J_J]

keep in mind one important constant and that is, increasing the pressure also increases the chance of blowing a packing or rod seal and both are expensive to replace both in time removing the cylinder and replacing the parts.

He only said he would increase the pressure to spec. You can only increase the pressure to the pumps max pressure. That is your source. All the different hyd components have different pressure ratings and the test failure rating is far and above the label on the hoses or cyl, etc.

A 100 psi change in the 2500 psi area, would increase the force by 314 lbs for a single cyl, and 628 lbs for two cyl That little extra just might be all he needs.

A 500 psi increase will increase a single cyl force about 1571 lbs. If using two cyl to push pull or tilt
double that force.

 

[Piston]

Should my L4610 be able to lift the rear off the ground relatively easy with the rears filled with 800lbs of rimguard?

 

[J_J]

What are the lift weight specs at the bucket pins?

The weight you lift and whether the back end will come off the ground is a matter of balance. If your tractor has the hyd pressure and large enough cyl, the balance point will be reached when the weight fwd of the front wheels weighs the same as the rest of the tractor behind the front wheels. A little more weight on the front will raise the backside.

They try to engineer these things so they will just meet design specs.

 

[dex3361]

What are the lift weight specs at the bucket pins?

The weight you lift and whether the back end will come off the ground is a matter of balance. If your tractor has the hyd pressure and large enough cyl, the balance point will be reached when the weight fwd of the front wheels weighs the same as the rest of the tractor behind the front wheels. A little more weight on the front will raise the backside.

They try to engineer these things so they will just meet design specs.

I agree. I have only lifted 1 wheel off of the ground with proper ballast. The only improvement on the LA703A loader would be a better roll back angle.

 

[Piston]

What are the lift weight specs at the bucket pins?

LA 852 LOADER

Loader weight with standard bucket approx. 1350 LB

Max lift height ... approx. ... 108.3"

Lift capacity ... 1830 LB
Lift capacity (pivot pin) ... 2470 LB
Lift capacity (bucket center)... 1875 LB
Breakout force ... 3055 LB
Reach at max. Height 18.5
Max. dump angle ... 45 degrees
Reach with attachment on ground 68.3
Max. rollback angle ... 35 degrees
Digging Depth 4.9
Overall height in carry position 55.1
Clearance with attachment dump 84.6
Std. bucket 72 wide
Std. bucket weight ... 300 LB
Raising time to full height without load 4.3 seconds
Lowering time (powerdown) without load 2.7 seconds
Attachment dumping time 2.0 seconds
Attachment rollback time 2.8 seconds
Rated Flow 9.6 gpm
Relief valve pressure 2560 psi