Quickie loader, very slow. WHY?

[oldnslo]

Jahmes
Did you give up on purchasing the flow meter and required hose and fittings?

 

[rScotty]

OK. It certainly is difficult to diagnose this problem remotely. My feeling is that it is not a part failure or we would have found it by now. That means it may well be a misconnection or control that we've not found - perhaps it was always so, since it does work...although slowly.

My guess is that we are missing an adjustment or connection back at the ports designated as accessory hydraulic connections which sit to the right side of the rockshaft casting. There pors are standard equipment on all this series of M Kubotas and are the obvious place to access hydraulic flow for the loader.
The WSM has a short section with a flow schematic that addresses the adjustment of these ports. It is out of sequence, being an addendum on the very last page of the WSM.

The more I study these 1995-2005 M4700 thru M6900 Kubotas, the more impressed I am with the way they are designed.

Choose your dealer mechanic carefully. And let us know what the resolution is.
& Thanks,
rScotty

 

[jahmes143]

@oldnslo I purchased the flowmeter and fittings, waiting for them to arrive. That could tell us something. I also messaged Alo and asked if they had any literature specific to this loader and control valve. Will report back on any developments!

@rScotty we also have an M5640SUD, bought new and now has ~2500hrs and we have been very impressed with it.

 

[jahmes143]

Was able to come across the manual for my valve (part 521641). See pages 41 and 42 where it appears to show 3 different configuration options.

 

[rScotty]

Was able to come across the manual for my valve (part 521641). See pages 41 and 42 where it appears to show 3 different configuration options.

Those 3 schematics on page 41 look the same to me except for the relief valve settings. Whatever difference in flow that those inset schematics are trying to show....well, I don't see it. Maybe I'm just missing it....or maybe they are referring to working cylinder geometry and not showing the "obvious" cylinder orientations. But if so, why make up schematics when a simple note would suffice?
mystified,
rScotty

 

[jahmes143]

Update...I got a flow meter and am getting 7-8gpm at 2000rpm and fluid at about 60 degrees. I believe pump is rated up to 11gpm but not sure what RPM that would be at. I will let the tractor warm up and re-test in a few days. Didn't have much time tonight.

This was tested by placing the flow meter in line, with the supply hose on one side (hose #1 in my prior pics) and the control valve on the other side.

 

[oldnslo]

Great job on getting the flow meter installed.

7 - 8 GPM should operate that loader at a reasonable speed. If pump is original to the tractor the flow of 11 GPM would typically be at rated PTO RPM or close to full throttle.

Going from memory without going back and reading all pages on this post I believe there was a block of some sort between the pump and loader valve. Is this block now between the flow meter and the loader valve? If yes is there anyway to move the flow meter in line between that block and loader valve? That would verify the flow is getting to the loader valve or not.

 

[jahmes143]

Great job on getting the flow meter installed.

7 - 8 GPM should operate that loader at a reasonable speed. If pump is original to the tractor the flow of 11 GPM would typically be at rated PTO RPM or close to full throttle.

Going from memory without going back and reading all pages on this post I believe there was a block of some sort between the pump and loader valve. Is this block now between the flow meter and the loader valve? If yes is there anyway to move the flow meter in line between that block and loader valve? That would verify the flow is getting to the loader valve or not.

Not sure what block you're referring to. Maybe that was a different thread? A top potential issue of mine was air getting in the lines. I replaced all O-rings on suction side and that didn't resolve the issue. I also confirmed pressures were within spec, and most recently confirmed flow to loader valve is acceptable. Maybe I need to try a new valve.

 

[oldnslo]

Not sure what block you're referring to. Maybe that was a different thread? A top potential issue of mine was air getting in the lines. I replaced all O-rings on suction side and that didn't resolve the issue. I also confirmed pressures were within spec, and most recently confirmed flow to loader valve is acceptable. Maybe I need to try a new valve.

Sorry on getting posts confused but if you have both flow and pressure going into the valve we next need to figure out where it is going.

Can you move the flowmeter to the power beyond line? I believe that line 3 in picture of the valve. When trying to raise at full speed do you see any flow? Same with curl or dump and full command?

If yes does the volume of flow change when cylinder hits end of stroke?

 

[jahmes143]

@oldnslo this tractor does not have power beyond. Post #27 shows hose 3 goes from the control valve to the rockshaft. I can still place the flow meter in line here and test if helpful.

 

[oldnslo]

@oldnslo this tractor does not have power beyond. Post #27 shows hose 3 goes from the control valve to the rockshaft. I can still place the flow meter in line here and test if helpful.

The line from control valve to rock shaft is the pressure supply to the rock shaft or commonly called power beyond from control valve. This is required for systems with fixed displacement type gear pumps. All of the valves or circuit functions must be in series for the function to operate.

Does the above explanation make sense?

 

[Sawyer Rob]

Yes, the pictures help a lot. We now know that your loader has a typical FEL control valve with what looks to be a power beyond port taking flow to the 3pt. Yours not having the rear remotes does simplify things.

To answer your questions best as I can.....That's clever to listen to the return that way and I'm not surprised you would hear the returning fluid when listening through the full cap. My guess is what you hear seems normal, especially since the return noise should stop when you work the loader and it does. The rest of the noise?? The bubbling?? Well, I am not surprised that there is some suction side air leak in 30 year old hoses, but my guess from the other things you've saidis that any suction leak is not the main cause of the loader being so slow.
Yes, lots of guesses here.

On the curl and raise not working simultaneously - that one is easy. Separating the functions is common when a manufacturer specifies an inexpensive loader control valve. Coupling the functions requires a more complex casting and additional machine work on the spools. So separate functions like you have ust means Quickie Loaders used a generic control valve instead of a more expensive one made to match your tractor. flow You can replace that valve with a better one that will bolt right up someday if you want. A better one will allow feathering both motions at once, and the best valves may also have some degree of internal fluid regeneration - which really does speeds up a loader.
All in all, some small part of the slowness is probably due to that control valve, but the valve shouldn't be slowing motion as much as yours does.

The photos are great! Now we can make some educated guesses, but because yours has power steering we probably still need the hydraulic schematic in the workshop manual for the Kubota M5400, do you have that manual? I can't seem to find one free online. The place I found the operator's manual - attached to post #22 - doesn't have a workshop manual.
However, there is an active market in old manuals on Ebay. Take a look there. The best are the factory workshop manuals - usually in printed form.

Any info we can get from Quickie Loaders about the model 310 loader and Kubota hookup would help too.

1st Photo:
Line 1 is the "P" or pressure line coming either from the hydraulic pump...OR from one side of a priority valve that separates the main hydraulic pump flow into a power steering flow that has priority and then the remaining flow goes to everything else.
Line 2 is the return to the "T" sump or Tank.
Line 3 is the power beyond that goes back to the 3pt. If we could see the side of the valve casting there should be a raised "PB" there. You should trace all these lines to confirm.

NOTE: IF LINES 1 & 3 ARE REVERSED into the Control valve, that could cause the loader to be slow. So be sure to trace those lines !

2nd Photo. Not sure what view this is. What are we looking at?

3rd Photo. From underneath? #2 should be going to the tank sump, but is it? I see some splits in that old hose where it bends, but if it is return to tank, those don't matter.
Is the steel line the suction line from sump tank to your filter?
What is the unnumbered hose?

Now we are getting somewhere.
rScotty

I have two of those loaders with THAT valve, both of them will do two functions at once!

The reason his loader is running slow is because he has it on a tractor that doesn't have a lot of hydraulic flow.

SR

 

[oldnslo]

Verified 7 GPM should move that loader faster than estimated 30 seconds to raise.

 

[Sawyer Rob]

Verified 7 GPM should move that loader faster than estimated 30 seconds to raise.

What post number did the OP say it took 30 seconds for the loader arms to raise?

I can't find it.

SR

 

[oldnslo]

What post number did the OP say it took 30 seconds for the loader arms to raise?

I can't find it.

SR

My bad, found post stating 10 seconds from full curl to full dump which is very slow with 7 GPM unless they are some good sized cylinders.

A 3 bore cylinder will extend at approximately 300 inches per minute with 7 GPM input flow.

Correction it should be approximately 230 inches per minute NOT 300 shown above.

 

[Sawyer Rob]

I have one ALO on a tractor that probably puts out the same at the remotes as the OP's tractor, and 10 seconds isn't far off.

My second tractor with an ALO had 15.9 at the remotes, and it has pretty good loader speed.

ALO loaders are pretty close to an industrial loader, and if you are used to the dinky loaders on compacts, they probably seem pretty slow, but the ALO will still be working when the little loader is in the junk yard.

And yes, I have those too,

SR

 

[oldnslo]

Sawyer
I went back through the posts and found the manual for the loader

It shows lift cylinders being 70mm bore with 40mm rod but don’t show stroke

Dump cylinder is 65 mm bore with 40 mm rod

70 mm =2.756 in
65 mm =2.559 in
40 mm =1.575 in

So using formula
IPM = GPM x 231 divided by cylinder area

2.75 in bore = 5.94 square in area

7 x 231 =1,617 divided by 5.94 = 272 inches per minute for one cylinder or 4.5” per second

Estimate 2.25” per second with 2 cylinders or 22.5” in ten seconds

With this information Jahmes can now do a couple of time vs cylinder travel distance measurements and determine if everything is good or is there a problem that needs further investigation.

Only took 6 pages of posts to get to this point

 

[jahmes143]

@oldnslo that's some fancy maths! Based on your calcs, I think (unfortunately?) my loader is functioning properly.

Lift cylinder: 18.5" travel
Dump cylinder: 19.5" travel

@1750RPM

Raise: 9.2 seconds
Lower: 4.3
Curl up: 8.0
Curl down: 5.3

I don't usually run it at 1750RPM, so perhaps I need to throttle up more while using the FEL. It's still virtually impossible to use 2 functions at once (raise & curl, for example). I supposed I'm just used to the Kubota loader on my M5640 which I swear is 2x as fast.

 

[oldnslo]

Jahmes,
Thanks for posting the actual travel distance vs time so that we now have closure on this concern.

Your Kubota might have a different style valve that directs the return oil from lift - lower to the curl - dump circuit. A quick way to test for that is operate a function like raise and then also attempt to lift the 3 point. If 3 point lifts you have a different valve style or a different pump style.

 

[jahmes143]

@oldnslo My 3 point will not raise when the bucket is raising or curling up. Given the above conversation (and thanks everyone for the education!), what are feasible options to increase the performance of the FEL? Do they make a higher output hydraulic pump? Put smaller cylinders in current FEL? Ditch this FEL and get another setup? Get a different tractor? Buy a new truck and trailer to haul my new tractor? "Honey, the guys at TBN told me I NEEDED to do it"!