L3710 gst no power steering once shifted into gear

[Lakelife]

I’ve been trying to diagnose if the tractor needs to be split for gst hydraulic clutch pack seal repair/ replacement. Today I was able to get a copy of the wsm and started doing the pressure readings of the gst system, relief valve settings, pilot pressure and clutch pack pressure.

gst system pressure was 370

Relief valve setting pressure was a little low at 400 but trying to turn the adjuster didn’t seem to increase.. seemed to already be bottomed out so didn’t want to force it so moved on.

Pilot pressure I can get about 350 as soon as you shuttle shift into gear but then pressures fall to around 200. (This is also when the power steering stops working)

I stopped testing at this point as clearly there is an issue with the pilot pressure circuit.

guessing I need to look at the pilot orifice or modulating valve next or is this looking like the clutch pack issue??

 

[North Idaho Wolfman]

What is the pressure at the pump before anything?
Because what your explaining sounds like the pump is going out and that's why you can't get the pressure up.
I had the clutch pack seals go completely south and it never effected the steering on mine.

I've also had issues with a bad suction line causing issues and a bad filter causing issues.
I would look into those before you even consider a tear down.

To do the GST clutch pack it requires the transmission to be completely torn down, it's quite a task.
No for the faint at heart.

 

[Lakelife]

What is the pressure at the pump before anything?
Because what your explaining sounds like the pump is going out and that's why you can't get the pressure up.
I had the clutch pack seals go completely south and it never effected the steering on mine.

I've also had issues with a bad suction line causing issues and a bad filter causing issues.
I would look into those before you even consider a tear down.

To do the GST clutch pack it requires the transmission to be completely torn down, it's quite a task.
No for the faint at heart.

What is the pressure at the pump before anything?
Because what your explaining sounds like the pump is going out and that's why you can't get the pressure up.
I had the clutch pack seals go completely south and it never effected the steering on mine.

I've also had issues with a bad suction line causing issues and a bad filter causing issues.
I would look into those before you even consider a tear down.

To do the GST clutch pack it requires the transmission to be completely torn down, it's quite a task.
No for the faint at heart.

Thanks for the reply, I really hope you’re right as I’d rather not tear it down. The tractor does seem to have a lot of power in gear still. Takes a second or maybe 2 to start moving when you shuttle theft it but doesn’t seem out of the normal. The only test as far as the pump goes was the relief valve test that I did by hooking my gauge to the test port on the pump and got the 400psi. Is there something else I can do to test it as well?
The rubber part of the pickup tube does look original which I’ll order a new one and change the filter to begin with since it sounds like it could be an issue.

 

[Lakelife]

Thanks for the reply, I really hope you’re right as I’d rather not tear it down. The tractor does seem to have a lot of power in gear still. Takes a second or maybe 2 to start moving when you shuttle theft it but doesn’t seem out of the normal. The only test as far as the pump goes was the relief valve test that I did by hooking my gauge to the test port on the pump and got the 400psi. Is there something else I can do to test it as well?
The rubber part of the pickup tube does look original which I’ll order a new one and change the filter to begin with since it sounds like it could be an issue.