Loader L3800 hydraulic power loss?

[sadie72]

Hello All,

Last night I was loading a #650 log splitter into the bed of my pickup with a strap and my QA forks. My loader got to a height where it wouldn't go any higher eventhough there was plenty of cylinder remaining; couldn't even curl forks for additional height to clear the truck's sidewalls. I've done this before with no problem with the same everything, except this time I have a #800 winch on the 3pt. In the past I had the BH77 backhoe on the tractor that attaches to the subframe, not 3pt. Having the winch on the 3pt shouldn't reduce the capacity of the loader, should it? I also noticed recently that I can't lift the front end of the tractor slightly by curling out the front bucket before using the winch to pull logs out. What gives? Do I have a potential hydraulic pump issue, or can the heavy 3pt attachment reduce hydraulic capacity of the loader?

Thanks for any input.

 

[k0ua]

Hello All,

Last night I was loading a #650 log splitter into the bed of my pickup with a strap and my QA forks. My loader got to a height where it wouldn't go any higher eventhough there was plenty of cylinder remaining; couldn't even curl forks for additional height to clear the truck's sidewalls. I've done this before with no problem with the same everything, except this time I have a #800 winch on the 3pt. In the past I had the BH77 backhoe on the tractor that attaches to the subframe, not 3pt. Having the winch on the 3pt shouldn't reduce the capacity of the loader, should it? I also noticed recently that I can't lift the front end of the tractor slightly by curling out the front bucket before using the winch to pull logs out. What gives? Do I have a potential hydraulic pump issue, or can the heavy 3pt attachment reduce hydraulic capacity of the loader?

Thanks for any input.

Ok, lets get thru the easy question.. I don't care what you put on the 3pt, it is not going to changewhen the pressure the relief valve opens. The fact you cannot make a lift you have made before and the fact you cannot lift the front of the tractor with the bucket, which you did before indicates a problem. You need to buy an hydraulic pressure gauge, and the necessary adapters to put this gauge on your hydraulics and test the relief pressure. I cannot remember what the relief pressure is supposed to be for the L3800 but is is somewhere around 2500 lbs. My guess is you are not able to get anywhere close to this relief pressure now. Either your relief pressure valve spring has went weak. or the access bolt to this valve has come loose and not providing any preload on the spring, or you truly do have bypass in your pump. Find the PRV (pressure relief valve) Make sure the bolt is not loose. The spring and its shims will be under this bolt.

 

[sadie72]

I checked the bolt and it is fine. The original paint isn't even cracked. I'll look into checking the pressure. Manual says 2277psi with max of 2347 psi. Is there a convenient location to tap into the hydraulic system? Are there pressure gauge kits available that can be mounted and left in place?

Thanks for the reply, and where did you get that handy diagram?

 

[Gordon Gould]

Were your rpm's the same both times - and above idle ?

 

[sadie72]

Don't recall, but yesterday when it wouldn't lift as expected i tried again at 2400 rpm.

I will check my loader hydraulic pressure tomorrow if the rain stops.

 

[k0ua]

I checked the bolt and it is fine. The original paint isn't even cracked. I'll look into checking the pressure. Manual says 2277psi with max of 2347 psi. Is there a convenient location to tap into the hydraulic system? Are there pressure gauge kits available that can be mounted and left in place?

Thanks for the reply, and where did you get that handy diagram?

From the Kubota website.
Kubota Tractor Corporation - Parts List

Bxpanded sells a kit, or you can put together every thing you need from surplus center or discount hydraulic hose.

 

[Hammer Head]

I am looking to shim my pump. Sent an email to Bxpanded asking if they had a kit to check the pressure and shim kit.
They responded with they do not have the coulplings for the L3800 and can not help at this time!

 

[sadie72]

Okay, $47 later and I tested the pressure at 2200psi. In my opinion, this is not too bad with respect to the manual's recommended 2277psi. Would you agree the pressure isn't a concern? Should i try to get the pressure to 2300psi? Would this make an appreciable difference in lifting capacity?

 

[LD1]

Okay, $47 later and I tested the pressure at 2200psi. In my opinion, this is not too bad with respect to the manual's recommended 2277psi. Would you agree the pressure isn't a concern? Should i try to get the pressure to 2300psi? Would this make an appreciable difference in lifting capacity?

On that loader, 100psi should amount to about 100# of lift at the pins. A little less at the bucket edge.

A 650# splitter should lift just fine at 2200psi. ANd you should have no issues lifting the front of the tractor by curling down. You got something else going on.

The gauge you got, where did you put it? And can you get a tee and some fittings so you can tap it into the loader lift WHILE you are lifting?

I'll post a picture of mine as soon as I can dig one up.

 

[LD1]

Found them. Can you do this? and see what the gauge reads while trying to lift something heavy?