John Deere 445

beenthere · Mar 28, 2015

The parts schematics are available to anyone, through jdparts.com and free registration to boot.
That will show the breakdown of the control valve assembly and relief valves.

Because the OP explained that the power steering is also not working, and that it is priority in line ahead of the hyd control valves, seems to me that the problem wouldn't be in the relief valves at that location. But may be worth a try to clean them up.

narampa · Mar 28, 2015

beenthere said:
The parts schematics are available to anyone, through jdparts.com and free registration to boot.
That will show the breakdown of the control valve assembly and relief valves.

Because the OP explained that the power steering is also not working, and that it is priority in line ahead of the hyd control valves, seems to me that the problem wouldn't be in the relief valves at that location. But may be worth a try to clean them up.

I agree except for the fact that from what I see any relief valve in the circuit will effect both. There is a possibility that I am incorrect. However the next step is to remove the fenders fuel tank and get into the valves on the trans axle. Like I said don't start ripping and tearing. Easy things first!

beenthere · Mar 28, 2015

:thumbsup:

bear4020 · Mar 29, 2015

Sorry everyone. Had some boar goats Have kids. Been really busy with them. Will be checking out Deere soon.

narampa · Mar 29, 2015

bear4020 said:
Sorry everyone. Had some boar goats Have kids. Been really busy with them. Will be checking out Deere soon.

I think we are all waiting to get this thing fixed. Than we can get back to sleeping again.

narampa · Mar 29, 2015

One thing I would like you to try. With the engine stopped and you turn the steering wheel do the front wheels turn left and right.
If the steering valve is working correctly the wheels should still steer. If not do not assume that the valve is bad. Unless the steering wheel is seized and will not turn at all.
But we should know this as the steering valve has a connection back to tank. So we have to know where the oil is going.
Let us know what you find.

bear4020 · Mar 29, 2015

Yes. Wheels still turn left and right with the engine off.

narampa · Mar 29, 2015

bear4020 said:
Yes. Wheels still turn left and right with the engine off.

If that is the case than I would like you to remove the circuit relief valves on the flow chart that Been There supplied.
One is in between the two upper hose couplings. It looks like a bolt head. The other one is underneath the valve.
As per my earlier post. Let us know what happens.
If this does not work you will have to remove the seat and fenders.
So far we know pump is good and steering valve is good. We now have to find out where the flow is loosing pressure.

narampa · Mar 29, 2015

Here is a picture of the hydraulic control valve that has the hose couplers under your left foot. As you can see there are two lift check valves. These are the ones I want you to look at.
The color of the flow is yellow just as in the previous pictures.Which is pump charge pressure. If either of the two check valves are unseated a tiny little bit they will not allow pressure to build in either the steering or the hydraulic lift circuits.