7040 hydraulic shuttle

[JPauto]

I have a 7040 with les than 1000hrs.
The shuttle shift quit working (reverse wont fully engage) so I pulled the tank to adjust it.
I could never get more than 155psi for both the forward or reverse.
So I split the tractor and pulled the clutches. They were at the maximum allowance for wear, so they got replaced.
Put it all back together and I still dont have enough psi, and the gauge fluctuates rapidly.
I did change the fluid and filters but no luck.
Now the tractor dosen't even try to engage in reverse.
What's my next step, what am I missing?
Thanks in advance.

 

[SidecarFlip]

Getting a bag of popcorn for this one....

less than 1000 hours? I have 3 and 6 consecutively on mine and no shuttle pack issues with either. Lockup is progressive but firm Last spring I checked my open station (at 6K) and the pressure was right on the WSM call out and the gauge needle was rock steady. I did increase it just slightly because of the hours. Wonder if you have a blockage in the modulating valve?

 

[BigG]

This thread might help you. They say it is a cable problem. It is about the M5040 but the pages also say M7040 on them.

Dave eng knows his stuff and you might check with him if you need more help.

M5040 shuttle shift won't engage

My Kubota M5040 shuttle shift won't move with the engine running. When I try to put it in forward or reverse I can feel the tractor move a little but shifter won't move. Anyone have suggestions to cure this problem? Thakns.

www.orangetractortalks.com

 

[Dave_eng]

Do you understand the hydraulic flow to the shuttle clutches comes from the power steering controller?

Before tearing apart a 1,000 hour machine, please tell me what you did to diagnose the problem as I am concerned that your disassembly and reassembly may have just added more things that could be wrong now.

Does the pto clutch engage and carry a load.

What type of pressure gauge have you been using to measure the 3 shuttle pressure test points...... what is the maximum pressure of your gauge as 700 psi is the recommended maximum.

This max pressure range would be to control the extend of the error in any measurement as a typical gauge has an error of 5% of full scale so a 0-3,000 scale gauge can have an error of 150 psi. You are trying to measure pressures of around 300 psi so a 150 psi error is very misleading as to what the pressure actually is.

Which if the 3 test ports, F, R, M are you taking your fluctuating 150 psi reading from?

Dave

 

[SidecarFlip]

I find it hard to believe that the pack segments were at the allowable wear limit with 1000 meter hours. Something else is going on that we have no clue about. Wet clutches don't expire in 1000 hours, especially those that are completely controlled by a remote source with no human input other than actuation of the clutch pedal.

I can buy a wet pack in a motorcycle expiring in 1000 hours due to abuse from the operator but not an enclosed wet pack clutch with no 'human' input.

I guess you could if you constantly 'half clutched' the pack but I don't see any other scenario.

My foot would get tired of that pretty quick..................

Like the old saying goes... There is more to this story........

 

[SidecarFlip]

I use a 1000 psi liquid filled Wika gauge btw.

 

[JPauto]

1000psi gauge, both the "R" and "F" ports, exactly as the manual states.

 

[Dave_eng]

1000psi gauge, both the "R" and "F" ports, exactly as the manual states.

Manual also calls for M port to be tested
Dave

 

[JPauto]

Everything was "by the book"
Low pressure, and about a 75 psi flutter on the gauge.

 

[Dave_eng]

Everything was "by the book"
Low pressure, and about a 75 psi flutter on the gauge.

Was the pressure on the M port different than on the F & R ports?

And what about the pto clutch?

Dave