B7100 Weak 3 Pt. Hitch Lift

[DetroiTom]

I have a 1993 B7100 HST that has a weak lift on the 3 point hitch. It works fairly well when the hydraulic oil is cold, put after the hydraulic oil is heated up, it will squeal and jump when I attempt to raise the (150#) back blade. For some reason when I operate the Kubota OEM FEL controls at the same time it affects the 3 point operation , sometimes making it "snap out of it" and operate normally. The FEL works great. The tractor only has 180 hours on it, so nothing should be worn out. I have owned it since new.

Any suggestions for diagnosis would be greatly appreciated. Thanks!

[Bird]

I don't know if it's the same problem, but when I had a B7100, sometimes the 3-point wouldn't raise at all, and all I had to do was wiggle the joystick for the front end loader to make sure it was centered properly and then the 3-point would work properly. It does sound like you might have the same situation. If the FEL valve isn't completely closed, the 3-point hitch won't raise right.

[Rick Jay]

Tom,

Welcome to TBN! I'd check out Bird's suggestion. He speaks from experience.

On a different note, you have a 9 year old tractor with only 180 hours? Wow, your average is less then mine! I've only got 68 hours on my B2910 after 2 1/2 years. And I thought I had the most underworked tractor on the planet!

Let us know if Bird's suggestion was helpful.

~Rick

[DetroiTom]

Bird, I think you are on the right track. When this first happened I was able to wiggle the FEL valve and get it to work OK, but it doesn't seem to do the trick now. Any suggestions on how I might correct or diagnose the FEL control valve ? Thanks - this is a great group - like one big family!

[Bird]

Afraid I'm not much help; never had to do anything more than just wiggle the joystick on mine, and now I don't have any manuals anymore; let them go with the tractors. Maybe Kubmech will see this post and I'll bet he knows how to fix it.

[Thomas]

By chance does your B7100 have a control hyd valve??..maybe its not turn all the way open.

On my B7100 its located on the R.H. side under the seat on the frame.

Knob should have an arrow on it to show the flow.

[DetroiTom]

Thanks Thomas, I did check the control valve under the seat.

[Egon]

Mine will do the same but by moving the joystick out of float where it sometimes sticks all will work well.

Egon

[kubmech]

A sticking spool on the loader control could cause some problems but the fact that the loader always works properly seems to rule this out. The flow should be from the hyd pump to the diverter valve assy (near your right foot) to the loader valve back to the diverter back to the 3 pt valve. There is a relief valve in the loader control valve and a relief valve in the diverter valve. Can you tell where the squeal is coming from? Is it in the loader valve area the diverter valve area or the back of the tractor? From what you have described I would geuss that the relief valve in the diverter may be hanging up, if that is where the noise is coming from. Also check for any binding in the 3ph linkage. Do you have a mid mount mower installed? That too could be binding on the way up causing the relief to open. A sticking spool on the loader valve may be caused by the detent or return spring in the spool section. Check the fluid condition and make sure the suction screen is clean. Also make sure you don't have any small suction line leaks. Ther are quite a few things that can cause this condition and I need as much input as possible to help narrow it down.

[DetroiTom]

Art, thanks so much for taking the time to provide this list of diagnostic steps. I'll use a stethoscope to find out where the noise is coming from and I think I'll have my sticking relief valve located.