[coalcracker]

I plan to test a “new” used hydro pump that I installed. Low gear gets me 1 to 2 mph and hi gear gets me 4 to 5 mph per the phone app. Engine runs strong can barley climb small incline and almost come to dead stop. 15-40 oil in hydro. no foaming or air leaks into oil lines. engine at wide open is 3600 rpm. it’s a 75 444.
Want to check if it’s pump or the TCV? I checked all past threads and want to confirm that it’s ok to deadhead a gauge from the drain port of the TCV. I do have a later style TCV with the integral holding valve. Not exactly sure what PSI numbers should have when doing the “tree” test?
Second thing I don’t understand is how to properly set the spring /ball in the TCV on a newer type TCV. where is the adjusting screw?
I have a 3’ 1/4” line and I ordered a gauge which should be delivered early next week. So I plan to test next week. Just looking for some direction to make sure I’m not missing anything.

 

[sdunt]

Well. This diagram from the How the hydraulics work manual:

Points out where the Relief valve is and how the ball, follower and spring should be installed. The adjustment screw is the one the cap screws onto.
That 3 foot long 1/4 hydraulic line was what I use when I attach a gauge for testing.

The pressure settings for the tractors are documented in: https://www.casecoltingersoll.com/d...est Procedures Manual 9-99785_watermarked.pdf

 

[myerslawnandgarden]

Pressure alone is not going to give you much of an idea on the condition of your pump, it will however tell you if your relief valve is set incorrectly. Even the most worn out pump will develop rated pressure, it's the flow that you need to measure under pressure that will tell you why your ground speed is slow. Assuming that you know the specs of your pump, it will always provide the rated flow at "zero" system pressure. You want to note that flow number and then load the pump rechecking the flow. Normally 10% drop at the test pressure is considered acceptable, and more than that indicates a weak pump.

Bob

 

[dundee222]

Most any ag dealer or heavy equipment shop will have a Hydrosleuth. This [expensive,,] tool will measure pressure, flow, and temperature [important for flow evaluation]. Maybe worth a trip with the tractor in tow to have them test it.

 

[Lionel]

I think I'd take a quick peak under the tractor to see if your getting full movement of the travel spool. Doesn't cost any money.
Your linkages could be worn, or other items under there could be. First place to always start.

 

[coalcracker]

I think I'd take a quick peak under the tractor to see if your getting full movement of the travel spool. Doesn't cost any money.
Your linkages could be worn, or other items under there could be. First place to always start.

I can see the travel spool moving in and out fully on both the travel and lift spools. Linkages look tight from underneath. I have deck removed so I could get under it and moved the travel lever while in neutral so I could see forward and reverse spool movement. that’s why I was wondering if that spring and ball inside the TCV could be an issue as I read in prior threads.
I did have original pump leak and then bought a “new” used one as a replacement and that’s my first guess that’s it’s the pump and not the TCV.

 

[Lionel]

Okay, so if linkages and related parts are creating full movement of the travel spool, I don't think, it would be relief pressure. Do You hear the thing squeal when you're travelling? Typically if it's a pressure relief or similar, the hydraulics would make a squealing type of noise,, If it doesn't do that, likely not a problem.

Depending on that, in the absence of equipment to test that, I would think there are visual indicators of poor flow,

Assuming you are familiar with your tractor, @ full rated RPM,
Slow movement of tractor,, you already have that problem.
Lift system,, cylinders retract and extend slow,,
Do you by chance have a tiller for this? At full throttle, tines would turn slow,,
All indicators of poor flow.

Also assumes, no slippage at the pump couplers,

After all this, you likely have a decision to make, spend money to have it tested, Not sure of costs for someone else doing this, but around here, nobody does anything for less then $100. That $100 is about 1/2 the cost of a pump,, (depending where you shop.)

Don't go with this, but it is an example pump and cost,

https://www.princessauto.com/en/63-gpm-hydraulic-gear-pump/product/PA0008375370

I think, Scott posted a decent procedure to set pressures,, specially, if you've swapped out the TCV.

 

[coalcracker]

I hooked up 5k psi gauge to drain port on the newer type TCV. I put tractor in neutral position and engaged travel control forward at full open throttle engine is at 3600 rpm and the gauge read only 300 psi and in reverse it reads 400 psi. Seems low to me. I then tested lift control and gauge reads around 600 psi both up and down. I still need to do the tree test but before I do
Is the test in neutral gear even worthwhile to see if pump is shot?
When doing tree test i assume the test is done in low gear?
Any help to my questions much appreciated
I want to make sure that pump is shot before i go buy a new one. don’t want to just throw money at it but I’m guessing it’s the pump because ever since the original pump leaked and I replaced it with the “new” used pump the travel speed is slooooooww!
Update - did “tree” test against porch stoop and full open throttle forward low gear gauge read right at 1000 psi reverse was around 900 psi. tires started spinning but still have a very slow speed and the engine never skipped a beat.
I’m guessing need new pump???

 

[sdunt]

Pressures in the system with no or little resistance. aka in neutral will not produce much pressure. I have a full time gauge on my tractor and rolling along on the flat not really pulling anything the pressure will drop to 300 - 600 psi.

When you were doing the tree test, did you hear the relief on the valve squeal? you should be able to simulate the sound by running the lift to the limit and holding there, that should pop the relief for the lift which will sound similar to the travel relief valve.

 

[coalcracker]

Pressures in the system with no or little resistance. aka in neutral will not produce much pressure. I have a full time gauge on my tractor and rolling along on the flat not really pulling anything the pressure will drop to 300 - 600 psi.

When you were doing the tree test, did you hear the relief on the valve squeal? you should be able to simulate the sound by running the lift to the limit and holding there, that should pop the relief for the lift which will sound similar to the travel relief valve.

Yes on valve squeal. when i engage the lift and then when travel valve squeal against porch right after squeal happens then the tires spin. And when i got off the porch stoop tree test and drive it in yard getting 1 mph in low gear.
Do you think it’s the TCV spring broken?

Looking at Bobs previous reply he stated
Normally 10% drop at the test pressure is considered acceptable, and more than that indicates a weak pump.
So if I had 1000 psi against porch and 300 psi in neutral is that Bobs point that it’s more than 10% drop.

 

[myerslawnandgarden]

Yes on valve squeal. when i engage the lift and then when travel valve squeal against porch right after squeal happens then the tires spin. And when i got off the porch stoop tree test and drive it in yard getting 1 mph in low gear.
Do you think it’s the TCV spring broken?

Looking at Bobs previous reply he stated
Normally 10% drop at the test pressure is considered acceptable, and more than that indicates a weak pump.
So if I had 1000 psi against porch and 300 psi in neutral is that Bobs point that it’s more than 10% drop.

No, coalcracker you are again referring to pressure. My comment regarding 10% drop is directed at the flow from the pump first with no load and then again measured under simulated working pressure.

 

[Lionel]

So if I had 1000 psi against porch and 300 psi in neutral is that Bobs point that it’s more than 10% drop. NO.
Because you weren't putting any demand on the neutral test, so that doesn't tell you much.

At 1000 PSI on the porch test, I assume the wheels were spinning, so you never really triggered the relief because of the wheels spinning. I'd would of expected around 2000 psi on that test,,Might be wrong on that number, but the correct number can be found within the first couple pages of this manual,, page 3 or 4,, for those models,, yours might be a different newer model, so you'd want to find the next manual up,, in the service section, under hydraulics,

https://www.casecoltingersoll.com/d3/manuals/ServiceManuals/Hydraulic%20Test%20Procedures%20Manual%209-99783_watermarked.pdf

 

[coalcracker]

So if I had 1000 psi against porch and 300 psi in neutral is that Bobs point that it’s more than 10% drop. NO.
Because you weren't putting any demand on the neutral test, so that doesn't tell you much.

At 1000 PSI on the porch test, I assume the wheels were spinning, so you never really triggered the relief because of the wheels spinning. I'd would of expected around 2000 psi on that test,,Might be wrong on that number, but the correct number can be found within the first couple pages of this manual,, page 3 or 4,, for those models,, yours might be a different newer model, so you'd want to find the next manual up,, in the service section, under hydraulics,

https://www.casecoltingersoll.com/d3/manuals/ServiceManuals/Hydraulic%20Test%20Procedures%20Manual%209-99783_watermarked.pdf

That’s a good point about model # for my TCV since I retro fitted onto a 77 - 444. The TCV is a newer style with the internal holding valve feature so I have no idea what year tractor it came off of. Either way the chart you attached shows all to crack at 2100 psi.
I tried to push against car on concrete driveway and this time the wheels started spinning at 1200 psi in low gear forward
I guess it still doesn’t tell me when relief is cracking open because wheels spin every time I try to push against something

 

[dundee222]

Push test has to be done in high to adequately load the motor to stall.

 

[coalcracker]

Push test has to be done in high to adequately load the motor to stall.

Thanks. I will try it out tomorrow in hi gear and see what psi readings I get.

 

[Lionel]

Just wondering, that new TCV,, when did you stick that on? Same time as the pump? I don't suppose it would have a tag or model number on,, does it?

 

[coalcracker]

Just wondering, that new TCV,, when did you stick that on? Same time as the pump? I don't suppose it would have a tag or model number on,, does it?

The newer TCV was installed years ago and I drilled new holes to move the TCV back 5/8" or what ever it was so that the travel links could work properly. It worked fine for over 10 years with the newer TCV before the original pump started to leak. That is why I am leaning toward bad pump again since I bought a used one since it was cheaper.

 

[coalcracker]

Today I was able to do tree test in hi gear with gauge reading at 2100 psi and then engine would start to die out. I could hear the relief squeal at that point.
So does that indicate that the relief setting in the TCV is good?
Are we back to a bad pump?

 

[myerslawnandgarden]

I would consider the relief valve setting to be correct, a 2100 psi load will stall a 14 hp engine.

Bob

 

[coalcracker]

I would consider the relief valve setting to be correct, a 2100 psi load will stall a 14 hp engine.

Bob

The 14hp k321 was recently rebuilt bored 1 over and crank resurfaced etc whole nine yards. So I know engine is strong good compression and the engine was ready to stall out as soon as it hit the 2100 psi. I think I will try another pump.