Anyway to make my loader lift more

[ironpig70]

I have a Kubota B7800 with an LA402 loader and it has about a 900 pound capacity. Well I am moving wet heavy cly dirt and I am filling it to capacity. What happens when this happens is the loader will not lift. If I roll the bucket forward and lift up I loose some dirt but get it a little more off the ground. Not a major issue but it leads me to some questions.


1) Is there something wrong with the hydralics? Filter(s).

2) Is there so kind of cheap fix/way to increase my lifying capability?


This tractor is used with 1478 hours on it. Bought it from a rental company. Figured it may have seen some idiots behind the wheel but it was probaly taken care o alot better than most folks.

 

[kennyd]

1) You can get a gauge and check the pressure to make sure it's up to spec.

2) No, not really without risking damage to the tractor.

 

[JJZ 109]

I have a Kubota B7800 with an LA402 loader and it has about a 900 pound capacity. Well I am moving wet heavy cly dirt and I am filling it to capacity. What happens when this happens is the loader will not lift. If I roll the bucket forward and lift up I loose some dirt but get it a little more off the ground. Not a major issue but it leads me to some questions.


1) Is there something wrong with the hydralics? Filter(s).

2) Is there so kind of cheap fix/way to increase my lifying capability?


This tractor is used with 1478 hours on it. Bought it from a rental company. Figured it may have seen some idiots behind the wheel but it was probaly taken care o alot better than most folks.

I've got an LA403. As you say, they're only rated for around 900 lbs (1091 lbs. at pivot pin, 783 lbs. 19.7 inches forward). You may get a little more out of it by shimming the relief valve, but it's generally not recommended to mess with it too much.
First thing to do it get yourself a gauge and see how much hydraulic pressure you have to the loader. Then compare that with the range given in the shop manual. Some guys have posted on here that the factory sets them a little low purposely. I found that mine was not low at all.
I thought about shimming mine to bump up the capacity a tad. But after checking the pressure found it was actually at the high end of the range so I left it alone.
Hopefully a couple of our posters named Kenny will chime in here and point you in the right direction.

Looks like ya beat me by a few minutes this morning Kenny! Must have not been awake enough to see your post.

 

[20 20]

You may be treading on thin ice if your planing on pushing it more then it should be. I quess I'll be the 1st to say, if everything is within specs PLEASE, don't do something that may cause you harm.

 

[flyingcow]

You may be treading on thin ice if your planing on pushing it more then it should be. I quess I'll be the 1st to say, if everything is within specs PLEASE, don't do something that may cause you harm.

+1. Wet dirt, whether it's clay or gravel or loam...is heavy ****. If you got to bucket it far, I'd go 2/3 of a bucket. A lot of stress on FEL and tractor "frame". If it has a frame. If it doesn't, there is always that possibility of cracking the ears off of the motor and tranny. And that wouldn't be good.

 

[J_J]

I am not recommended you bypass safety, but if your tractor is out of warranty, it now belongs to you. You can do what you want. Yes you can increase the weight lifting capability. The tractor probably is set up with safety in mind. They are probably not tuned to max. You can increase what you have by increasing the pressure relief setting. You can perhaps get larger cylinders. If there is a problem with tipping, then extra weight on the back will help. A smaller bucket might help some. Using a boom pole for lifting would help.

I haven't seen to many lift arms buckled.

The extra lift capability may pose a concern for the front axle, wheels and bearings.

People have modified things since time began, and some work and some don't. If you want to do it , it is your choice.

Install a 3000 psi gage in the circuit, and check and/or set the correct relief. Some are set by a threaded bolt, and others by shims. Install the gage before the FEL valve, using a hyd tee.

Do you know what the tractor is supposed to lift as compared to what the tractor is lifting now?

Does your relief activate when you are lifting now

Your pump may be bypassing due to wear and tear. My PT-1445 was only lifting about half it's rated capacity. New pump fixed the problem.

 

[Argosy]

Or breaking the front axle housing, blowing tires, destroying bearings. It's hard to tell why the limit was set at 900 lbs., but with wet clay it won't take a lot to reach it.

I moved 150 yards of wet clay last summer with a rear scraper bucket in two days. It's a pain but if you keep at it and don't break the tractor you will get done pretty quickly.

 

[ironpig70]

Thanks everybody.

Think I will get a gauge and test this. So with a gauge I just put it in line with one of my loder hoses at a time and see what I get? And then compare this to the specs?


I'd rather not do something that will destroy the tractor or myself.

 

[jlsmith]

They set these specs for a reason. That is what the loader and tractor is designed for. If one changes or alters these specs i dont see a good outcome. It might not happen for some time but something good happen causing a large repair bill. Maybe its just time for a larger tractor that will handle the stuff your tryng to do. JMO
Jeremy

 

[jlsmith]

Thanks everybody.

Think I will get a gauge and test this. So with a gauge I just put it in line with one of my loder hoses at a time and see what I get? And then compare this to the specs?


I'd rather not do something that will destroy the tractor or myself.

There should be a test port some where on the tractor. ask your dealer and they should be able to tell you where that is. Good luck.

 

[ironpig70]

There should be a test port some where on the tractor. ask your dealer and they should be able to tell you where that is. Good luck.

Thanks I will contacting my dealer.

 

[texasjohn]

When I got my tractor, used, I had the same situation... needed to pick up more but relief valve was popping.

Took tractor to dealer for pressure test...cost $35....they discovered it was slightly under spec...added a shim....now just at high end of spec, barely over. It has made a TOTAL difference in what I can lift... be sure you have sufficient rear weight to balance the front load.

Recommend taking tractor to dealer... will cost you more to purchase the pressure gauge than pay the dealer.

 

[J_J]

Thanks I will contacting my dealer.

I don't believe your FEL valve has work port reliefs, so installing the gage at the input to the FEL valve is a good place to monitor the system pressure and trouble shoot the system.

You dealer probably will not go above the the recommended pressure.

 

[texasjohn]

In my case, spec is a range of something over 200 PSI... one thin shim (washer) increased pressure from under to just over spec...dealer didn't have thinner washer, left it in.

 

[ironpig70]

Looked at the loader control valve and mine has 4 hoses each connected via a quick connect (like an air fitting).

Was thinking of hooking up a pressure gauge to each one and see what I get. I feel this is an accurate test. Is my thinking on the spot or will I need a loaded bucket?

 

[jonyyuma]

Or breaking the front axle housing, blowing tires, destroying bearings. It's hard to tell why the limit was set at 900 lbs., but with wet clay it won't take a lot to reach it.

I moved 150 yards of wet clay last summer with a rear scraper bucket in two days. It's a pain but if you keep at it and don't break the tractor you will get done pretty quickly.

Yes, tire and bearing failures, Plus broken front axles, be careful handling max loads.

 

[jlsmith]

Looked at the loader control valve and mine has 4 hoses each connected via a quick connect (like an air fitting).

Was thinking of hooking up a pressure gauge to each one and see what I get. I feel this is an accurate test. Is my thinking on the spot or will I need a loaded bucket?

You could check it there. If your in specs i would leave it alone, if you increase the psi you could start blowing seals and glands in your cylinders.

 

[ironpig70]

After reading all your post I see that somebody way smarter than me designed this to carry a certain amount of weight and exceeding this amount can cause serious issues with the tractor and my safety.


I plan on checking the pressure and if it specs out then great. If it is below the specs then it will be sent to the shop for the pros to fix as this is not something I understand and am not comfortable trying to fix.

 

[Ford tractor]

After reading all your post I see that somebody way smarter than me designed this to carry a certain amount of weight and exceeding this amount can cause serious issues with the tractor and my safety.


I plan on checking the pressure and if it specs out then great. If it is below the specs then it will be sent to the shop for the pros to fix as this is not something I understand and am not comfortable trying to fix.

To test the pressure, take a hose off the control valve that goes to the cylinder. Then actuate the valve to pressurize the gage.

You have 2 choices to increase capacity. Bumping up pressure from 2400 psi to 2600 or 2800 will give you a boost and that's about free, shims are cheap and easy to add. It's literally a 5 min task. That will also boost the 3pt capacity a bit too.

The other way to increase capacity is to replace the cylinders with larger diameter cylinders. That's costly as cylinders are about 200-250 each.

Moving larger loads you will be more prone to tipping and potentially faster wear of the bearings etc. You'll need more caution and better maintenance. Spreading the rear wheels to the widest will be helpful and using a larger 3pt weight will be needed to keep the rear wheels down.

 

[texasjohn]

Ironpig, don't worry, your tractor was designed to be USED. Do it.

Just be sensible.... think for a second about how to baby it when it is under extreme load. Think of your rear wheels as a fulcrum. With lots of weight hanging off the 3ph, you can lift front wheels off the ground, thus no stress on front but all tractor, FEL and 3ph weight is on rear axle. Alternatively, insufficient rear weight and extreme weight in FEL will lift rear and combined tractor and FEL contents weight is on front axle. These are the extremes and of course you don't want either.

So, simply prepare for the load when you are going to do heavy FEL work.

Max pressure in front tires to keep them from rolling off of rims.

Heavy, heavy 3ph counter weight to reduce/avoid strain on front axle and tires. I hang about 1000lbs on 3ph when doing FEL heavy work.

Trust that with hydraulic pressure at high end of spec range the relief valve will protect you from overloading the FEL/hydraulic system.

Go have fun!!