Bump up lift capacity of L3400/LA463 Loader

[LD1]

Newbie here, been reading for weeks. Sorry to hijack. Anyone know the min/max pressure on my L3940HSTC? Loader is okay, but barely. When bucket really full, can only lift 4' in the air.

It should say in your owners manual, But I would guess somewhere around 2400-2600PSI is where it should be. Put a pressure guage on it and tell us what it is. And make sure it is at least a 3000psi rated hydraulic guage and not something you pull off your air compressor.

 

[jim_wilson]

You can plug your gauge into any port, as for the pressure on the B3200 it should be about 2250psi from the factory. I bumped mine to 2600# 2 years ago and nothing has broken yet and yes it did make a difference. Your hoe may seem weak because of the longer stick. Just a guess though.

The gauge and quick connect arrived from McMaster-Carr today. So I quickly put them together and went out and checked the pressure at one of the loader ports.

What I'm seeing is that it "spikes" up to about 2150-2200 Psi when I hit the loader valve on that circuit. I should be receiving the Workshop Manual in a few days - I'll look into upping the pressure once I get that. Does Kubota sell a shim pack or is it just as easy to use a washer? I know there was a post somewhere earlier in this thread that detailed how much more shim would give how much more pressure.

 

[kuboman]

The gauge and quick connect arrived from McMaster-Carr today. So I quickly put them together and went out and checked the pressure at one of the loader ports.

What I'm seeing is that it "spikes" up to about 2150-2200 Psi when I hit the loader valve on that circuit. I should be receiving the Workshop Manual in a few days - I'll look into upping the pressure once I get that. Does Kubota sell a shim pack or is it just as easy to use a washer? I know there was a post somewhere earlier in this thread that detailed how much more shim would give how much more pressure.

You can buy individual shims of various thickness. I can't remember what it is but the thinness shim gives about 40 psi. If you have a accurate caliper you can use a washer(s) to get your pressure up. Just be very careful with that method that you don 't over do things.

 

[kuboman]

The gauge and quick connect arrived from McMaster-Carr today. So I quickly put them together and went out and checked the pressure at one of the loader ports.

What I'm seeing is that it "spikes" up to about 2150-2200 Psi when I hit the loader valve on that circuit. I should be receiving the Workshop Manual in a few days - I'll look into upping the pressure once I get that. Does Kubota sell a shim pack or is it just as easy to use a washer? I know there was a post somewhere earlier in this thread that detailed how much more shim would give how much more pressure.

You can buy individual shims of various thickness. I can't remember what it is but the thinness shim gives about 40 psi. If you have a accurate caliper you can use a washer(s) to get your pressure up. Just be very careful with that method that you don 't over do things.

 

[Summitsrule]

It should say in your owners manual, But I would guess somewhere around 2400-2600PSI is where it should be. Put a pressure guage on it and tell us what it is. And make sure it is at least a 3000psi rated hydraulic guage and not something you pull off your air compressor.

2450 PSI.

Manual is a bit confusing. Tractor manual clearly shows 17.7 MPa as the system pressure in the hydraulic unit. But the loader manual, LA724, shows maximum pressure as 18.1 MPa.

17.7 MPa = 2560 PSI
18.1 MPa = 2630 PSI

So good guess at your 2400-2600, I think 2600 PSI would be a good target.

Thoughts?

 

[LD1]

2450 PSI.

Manual is a bit confusing. Tractor manual clearly shows 17.7 MPa as the system pressure in the hydraulic unit. But the loader manual, LA724, shows maximum pressure as 18.1 MPa.

17.7 MPa = 2560 PSI
18.1 MPa = 2630 PSI

So good guess at your 2400-2600, I think 2600 PSI would be a good target.

Thoughts?

I havent seen your manual, so this is just a guess, but I'd say:

Your tractors relief is probabally set to the 2560, and the loaders relief set a bit higher than that. Which dont mean that the loader is getting anymore pressure than the 2560.

 

[Summitsrule]

I havent seen your manual, so this is just a guess, but I'd say:

Your tractors relief is probabally set to the 2560, and the loaders relief set a bit higher than that. Which dont mean that the loader is getting anymore pressure than the 2560.

I didn't think loaders have a relief.

 

[LD1]

I said it was just a guess as I am not familiar with that model.

But, it could also be that the LA724 is made for more than just one tractor. So it has to be "rated" at least as high as the highest pressure tractor it is put on.

 

[madmax12]

Removed - edit

 

[kcender]

I didn't think loaders have a relief.

I know my 3240 has a PRV for my loader so the 3940 would have as well.I used it to adjust the pressure for my loader which made a difference in it's performance.I used shims from Kubota which are very cheap,I wouldn't use regular washers but thats just me.