Hydraulic problems Power Trac 1850

[PowerT1850]

It is a Kubota V1200 and when I seach for this it seems that itｴs between 22,5-28 hp. What can you recommend:
PTO? VSP? Wheel motors ( with drain hose or not)? This is very useful for me though I must buy new parts. I have tried with more mail to Terry, but no answer.

 

[J_J]

This data suggest the HP is about 30 HP.

V-1200

M-35 75.5 cu in 30 hp @ 3,200 rpm

If that is true, then there are PT owners on the forum that have 1430 PT's and the might know the size of the VSP pump and the other pump displacements.

Is there any way for you to determine if that engine is the original engine.

What ever you do, the engine can supply so many HP, and that has to be divided between the VSP, the PTO, and the steering and lift.

 

[PowerT1850]

Yes, The Kubota seems to be the original engine. http://www.tractorbynet.com/forums/power-trac/213825-pt-selling-used-1850-72-a.html
But it says it is a 1989 420, but when I spoke to Terry he says it is a PT 1850 I have. What is right? I would be nice to get a contact to an owner of this.

 

[J_J]

Another PT for sale.

Power Trac PT1430 4x4 Diesel Compact Wheel Loader Snow Blade Mower Low Cost SHIP | eBay

 

[J_J]

Yes, The Kubota seems to be the original engine. http://www.tractorbynet.com/forums/power-trac/213825-pt-selling-used-1850-72-a.html
But it says it is a 1989 420, but when I spoke to Terry he says it is a PT 1850 I have. What is right? I would be nice to get a contact to an owner of this.

The current 1850 are 65 HP, and if the V-1200 Kubota is only about 30 HP, then all the pumps and wheel motors will be different.

Your machine might be older than my 1445 which has a 45 HP FORD Industrial gas engine. The people at Power-Trac should be able to provide you with a parts manual.

If you have talked to Terry, he should be able to email you everything they have.

They sent me a parts breakdown of my VSP pump, which is made by Eaton.

 

[PowerT1850]

A VSP pump that gives 6 GPM at 1800 rpm, does this give 12 GPM at 3600 rpm? What wheel motors for a PT1845 - PT1850? Is aprox.4500 in-lbs and 160 rpm ok? Open circut or close? What advantages disadvantages? What is enough for lifting and tilt GPM and PSI. How does displacement effect parallel / Serie couple? Many questions!!! Sorry but I must seek answered before I can go further.

 

[J_J]

Can you verify the diesel engine HP ?

Look at this chart at the M-35 which is Kubota v-1200, it is a 30 HP engine.

So based on that, I don't know why Terry is telling you it is an 1850.

If it is a 30 HP diesel, then all the 1430 hyd should work in your machine if you can find a pump adapter to match up to the Kubota engine.

There is a list of PT owners on this forum, and some of them have PT-1430's.

You might send each of them a PM requesting any data they can give you relating to pump and wheel motors and hose layout from pump to the wheel motors, and back to pump. . .

I think we all are willing to help, but you need to come back with certain data we ask for.

Look at the wheel motor hoses and determine how they are connected, draw a schematic of the hoses and wheel motors and pump configuration. Then we perhaps can provide more data.

The wheel motors and pump are configured for closed loop operation, whereby the fluid is circulated through the pump and wheel motors. Any fluid that bypasses the wheel motors goes out the case drains and to pump case drain, and then to radiator, then to tank.

My VSP also has a charge pump that provides any makeup fluid that was bypassed. All this fluid comes through a suction filter at the charge pump. Hydrostatic transmission need very clean fluid.

Logic would imply that a pump that can pump 6 GPM at 1800 rpm, can pump 12 GPM at 3600 rpm.

 

[J_J]

A VSP pump that gives 6 GPM at 1800 rpm, does this give 12 GPM at 3600 rpm? What wheel motors for a PT1845 - PT1850? Is aprox.4500 in-lbs and 160 rpm ok? Open circut or close? What advantages disadvantages? What is enough for lifting and tilt GPM and PSI. How does displacement effect parallel / Serie couple? Many questions!!! Sorry but I must seek answered before I can go further.

Pump displacement will determine the GPM given a certain engine rpm.

Your pump and motor probably a closed loop setup.

Motor displacement will give a certain rpm given certain GPM's.

If you flow 12 GPM through two 18 cu in motors at 3000 psi, in parallel, the GPM is divided between the two motors, each motor will get 6 GPM , and the rpm will be 77 rpm.

Possible scenario.

If VSP pump is 12 GPM at 3000 psi: 26 in diameter tires

Two 18 cu in, 1500 psi motors in series, 77 rpm , torque = 4299 in lbs, each.

Front two motors are in series.

Back two motors are in series,

Front and back are parrallel to the pump, one input and one output, so 6 GPM goes to the front, and 6 GPM goes to the back.

MPH will = 6

Torque = 1433 ft lbs

 

[J_J]

Hi, Thanks for help all of you. wdchyd is right it is Hydura I now find an exact same at Surplus center : .86 CU.IN./ .20 Cu.IN. | Piston & Hydrostatic Pumps - Quadra Trading Corp . this will make it a little easier I guess. I hope I can find the assembly drawing somewhere. My forward / back is controlled by solenoids, but the speed is manual lever from the pump. The Hydura pump at Surplus center is it used? Some warranty? You think.
PowerT 1850

Based on the displacement, the GPM's would be about 9 GPM, at 3000 psi, using about 18 HP from the engine

Do you know what the pump on the side of the engine attached to the flywheel is used for.

One of the gear pumps is for the PTO, and the other gear pump is for steering and lift.

 

[J_J]

Do you know you can use the fluid in a gear pump to determine the cu in capacity?

Drain all fluid from the pump, and then fill it full. Then turn one revolution and measure what comes out, and then convert the oz's to cu in .

For instance when you turn the pump one revolution and get 3 oz's, that will compute to a 5.414 cu in pump.

Capacity and Volume Conversion

Select fluid oz on left , and cu in on right side

Insert a number. You have your answer.