Testing a PTO pump

   / Testing a PTO pump #1  

NCMau

Gold Member
Joined
Nov 5, 2009
Messages
293
Location
NC
Tractor
MF 202/Ford 8N
I am planning to install a PTO pump to run a loader. Presently the loader is run by the onboard hydraulic pump. Before I start fabricating, I would like to know if this pump is working properly.
Is there a practical way to test this pump without a full blown plumbing job?
BTW, if the pump works, I plan to install a tank behind the seat.
 
   / Testing a PTO pump #2  
I am planning to install a PTO pump to run a loader. Presently the loader is run by the onboard hydraulic pump. Before I start fabricating, I would like to know if this pump is working properly.
Is there a practical way to test this pump without a full blown plumbing job?
BTW, if the pump works, I plan to install a tank behind the seat.

watch this little movie from wdchyd.....a test with a pressure gauge and a flow meter..
 
   / Testing a PTO pump #4  
Practical way without a hyd test set.

If you don't have access to the flow gage, then plumb a valve with relief set around 2250 psi, and cylinder/hyd motor with hoses and tank, and run the tractor PTO through the rpm range. Do you know the specs on the PTO pump, as to GPM's and pressure.

Next option would be to take it into a hyd shop and let them put it on their test bench.
 
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   / Testing a PTO pump #6  
Tried to give a 5 star on video, but mini pincher sits on my shoulders bumped my arm when I clicked, so I guess it is a 4 star!!!:laughing:

Thanx Mmurphy & Akkaman,

There is a way to do a flow test without a flow meter.....I used to do this years ago....

First, take a clean 5 gal plastic bucket and mark it off in 1 gal increments...

Second, set up an external direct acting relief valve at working pressure of your hydraulic system....you may need help from another hyd system or preset at factory.....

Third, connect a test hose from output of pump to a tee (one end of tee to a needle valve, other end to the preset PRV......

Now here's the fun part......

Have another clean 5 gal bucket right next to marked off one.....

Make sure reservoir is filled.....start tractor with needle valve open(or just open hose ) to unmarked bucket...move oil flow to other bucket at the same time you start timing.....this will allow you to figure your GPM with a stopwatch......Using two buckets will allow you to time it just right.....just have someone to help with the master the on/off switch......

Once you have figured out what the GPM's at 0 PSI, then do the same with the needle valve forcing the flow thru the PRV using the same method.....This will give you approx GPM's at high pressure

Remember, you don't need anymore than idle to show strength of pump and you do not need to fill bucket....only enough to give you an idea of what GPM comes out of open hose or PRV......

Let's say you get 1 gal at 0 psi at 10 seconds........that's 6 gpm's.........use your noodle to figure the ratio of Gals vs Time.......

Then at 2500 psi doing the same test you get 3 gpm's .......That's 50% effenciency at 2500 psi......

Do this test with a cold hyd system, then hook back up everything and warm up hyd oil (sometimes just actuate valve and deadhead against PRV built in to the tractor till it warms up)......then repeat everything with a warm/hot hyd system......See if it's get's worse (it shouldn't)

This is where I draw the line at replacing a hyd pump......50% or less.........

Yes, It'll still work OK (slower but still able to do work) but it's on the way out.....

Then start seeking out rebuild or repair of hyd pump....

If everything checks out then at least you can be confident of your pump....

I'm really surprised that I haven't read here on TBN about this form of test with the 5 gal bucket......but then again that's me:D
 
   / Testing a PTO pump
  • Thread Starter
#7  
The 5 gallon bucket is an interesting and ingenious approach and I may have use it if I can't find the capacity of my pump. The pump I have is a Prince C-387 and it is similar to the one J.J. linked me to.
While back I did inquire the company about the specs, but do you think they would give me specifics? Nooo!, they just linked to newer models, but no straight answer.
Anyway, I just about convinced myself to install the tank in back of the seat.
The tank I have is about 5 gallons which should be sized with the pump I am using. Tank capacity 2X pump gpm. Is this the general rule? Or can I go 1X1 for a loader?
I guess before I do anything I need to find the pump gpm. Does anybody have a clue about the capacity of this Prince C-387 pump? I would love to hear from you.
I have an attached sketch of the test system I have in mind, minus flow meter (these meters are gorgeous, but pricey, maybe later, right now I have other priorities).
Just want to confirm if this system is doable.
Thanks for all the help so far.
 

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   / Testing a PTO pump #8  
The 5 gallon bucket is an interesting and ingenious approach and I may have use it if I can't find the capacity of my pump. The pump I have is a Prince C-387 and it is similar to the one J.J. linked me to.
While back I did inquire the company about the specs, but do you think they would give me specifics? Nooo!, they just linked to newer models, but no straight answer.
Anyway, I just about convinced myself to install the tank in back of the seat.
The tank I have is about 5 gallons which should be sized with the pump I am using. Tank capacity 2X pump gpm. Is this the general rule? Or can I go 1X1 for a loader?
I guess before I do anything I need to find the pump gpm. Does anybody have a clue about the capacity of this Prince C-387 pump? I would love to hear from you.
I have an attached sketch of the test system I have in mind, minus flow meter (these meters are gorgeous, but pricey, maybe later, right now I have other priorities).
Just want to confirm if this system is doable.
Thanks for all the help so far.
I do not like a few things on your test set up.
First a safety issue! There have to be a relief valve between the pump and the needle valve!!!
oil_injection_injury.jpg


Second, I want the pressure gauge before the flow meter (this is of minor importance, but will include, the very small, pressure difference caused by the flow meter)
 
   / Testing a PTO pump #9  
If you have a larger hydraulic motor with a known displacement, one can hook the motor on a work port (return to tank). Put the needle valve between the Control valve and the motor.....use PRV in control valve for safety...

No put a counter on the motor shaft, to count how many turn it makes over 30 seconds....
Note that there shall be NO LOAD on the motor shaft....

if motor displacement is 1 cui and it makes 691 turns in 30 seconds the pump flow is 6.0 GPM.....internal leakage in control valve uncounted for, can be eliminated if control valve is excluded, and replaced with a PRV.....no bucket needed....
 
   / Testing a PTO pump #10  
Akkaman,

You've just brought back a memory of a "Shop Tour" I did 3 yrs ago while visiting family in Miss.....(I always have to snoop around when wandering off out of town:laughing:)

This company....http://www.geartek.com/......their test stands for new pumps were using gear motors with photo tachs on the output shafts to determine GPM output...... the exact principle you speak of here......They had several test stands with different setups and some rather large displacements.......


:thumbsup:
 
 
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