B 26 backhoe running slower and slower

[Gary Fowler]

That looks pretty simple to do IF you had all the equipment. Equipment doesnt look cheap though. I dont think it is a hydraulic problem with flow because the FEL works as it should. I am almost positive it was either filter stopped up, although the oil was clear when I changed the filter, OR the RV for the back hoe has slacked off allowing by-pass at a low pressure

 

[Gary Fowler]

FWIW Gary, I'd do it for you free if you were nearby....

Thanks, but I dont think it is a pump flow problem. Might be a problem with the control valves not opening all the way as someone posted. I will have to check that when weather warms up a bit or after Christmas I may just pull it in the shop and take a look. I dont want to oil up my shop floor with disconnecting hoses and such but I can do the check for loose connection on the joystick. I may just put a thin shim under the RV and see if it improves. I am going to Houston in 10 days for Christmas holidays. Maybe I can find a dealer there that can sell me the gauges to check the RV pressure.

 

[EE_Bota]

Easy tests...raise the FEL all the way to the top and try to raise it higher....listen carefully. That is a relief valve sound.
Raise one of your outriggers all the way to the top. Try to raise it higher...listen carefully. That is a relief valve sound.
Are the relief valve sounds coming from the same place? If so, there is likely only one relief valve. This means that you can attach the pressure gauge in a variety of places on the FEL, Back Hoe, quick connects, etc.

On my tractor, my FEL valve stack stays with the loader. On some tractors, the FEL valve stays with the tractor even with the loader off. For those, all that is needed is one quick connect half of the correct gender to connect to a place where the FEL connects. That is how I would attach my gauge in that case.

 

[wdchyd]

Hey wdchyd, what would be a fair price for that test?

Typically I would normally quote $50 if it's a quickie setup......This flow test will test for max pressures, pump efficiency, temp, air entrainment (fluctuating and jumping needle), clogged suction strainer or hose, will deliver an induced load and will show how much of a load while operating anything downstream

Not that expensive when you consider the other option is playing musical chairs with hydraulic components

 

[wdchyd]

Might be a problem with the control valves not opening all the way as someone posted..

Yes, check the stroke on them, make sure even the ones you are not using are self-centering too

 

[woody]

ok if I remember correctly there is relief valves on the backhoe but they are set higher than the relief valve on the tractor. the relief on the tractor is behind the right rear wheel, use the outrigger on the backhoe to raise the tractor. there looks like three relief valves on the bottom of the valve it is the small one and it does not take much to change it. I am going by memory so I hope someone else will check me on this.

 

[don white]

I am real interested to know if your problem is the control valve linkage coming loose. If we are both having the same problem then we have a design problem.
If you have time just check the amount of free play in the controls. When working properly the system is pretty tight and you can feel the valves in all directions. You don't even need to start the machine.

 

[Gary Fowler]

The levers dont feel like they are loose when operating and everything self centers. The Yanmar when it got loose, I could tell it was a problem with the connections. I dont think the tractor RV is the problem either and if as described, it is behind the wheel, I wont have to mess with that one as the FEL will lift a huge load with no problem and cycles quickly. If I get the notion tomorrow I will check it out a bit. Weather has really turned nasty cold at least for here in Ark. Supposed to be in the low 20's possibly even in the teens in the morning, 29f and falling right now. I dont relish handling those cold bolts anymore now that I am retired and can just wait out the weather till I like it without rushing into jobs as I previously did.

 

[Gary Fowler]

Well I finally got off my duff and did a little checking with the backhoe. Went over to back pasture and tried the hoe. Man did they screw up the operation on the hoe. I worked at it for about 10 minutes and gave up. In order to dig, you had to push one lever forward and pull back on the other which I didnt like at all. The way it was set up, you pulled both levers for dipper and boom toward you to raise and away from you to lower. I came back to the shop and put the hoses back the way they were. While in there I found 4 RV on the controls that were set by allen head screw on top. No shims required at this point. On my Yanmar, screwing the allen head in increased the pressure on the FEL so while I had the cap off, I turned them all clockwise about 1/2 round. Hoe seemed weaker than it was before. Maybe I went the wrong way. Any suggestions are appreciated
Anyone know how to set these on a B26. I didnt want to move it too much without a pressure gauge attached. I need to take a photo of the control console I guess so maybe someone can advise of the set process.

 

[EE_Bota]

Well I finally got off my duff and did a little checking with the backhoe. Went over to back pasture and tried the hoe. Man did they screw up the operation on the hoe. I worked at it for about 10 minutes and gave up. In order to dig, you had to push one lever forward and pull back on the other which I didnt like at all. The way it was set up, you pulled both levers for dipper and boom toward you to raise and away from you to lower. I came back to the shop and put the hoses back the way they were. While in there I found 4 RV on the controls that were set by allen head screw on top. No shims required at this point. On my Yanmar, screwing the allen head in increased the pressure on the FEL so while I had the cap off, I turned them all clockwise about 1/2 round. Hoe seemed weaker than it was before. Maybe I went the wrong way. Any suggestions are appreciated
Anyone know how to set these on a B26. I didnt want to move it too much without a pressure gauge attached. I need to take a photo of the control console I guess so maybe someone can advise of the set process.

You really need a diagram...One of the kind fellows here posted his diagram a while back for his, but probably for a different hoe, and it was chocked full of reliefs. But most of them were doing a accel/decel control or it could be thought of as an anti-shock or anti-hose burst control.

For example, imagine swinging your boom while it is way extended, and full of dirt. If you slam the valve open, it will relieve while accelerating up to speed. Suppose you then slam it into center position...instead of coming to an abrupt stop or busting a hose, it would relieve to a stop.

I wish I could be more helpful. I just don't know enough about your setup.

Edit: rScotty posted the example diagram.
http://www.tractorbynet.com/forums/...ckhoe-swings-right-but-not-2.html#post2870330

His tractor had a separate swing pump for boom swing. It was a fascinating example. I was a bit slow on the uptake during that thread. Earlier in the thread, I posted a generic diagram for reference and the real beast was far more complicated.