Auxillary Valve 450 PS

I'm getting about to wits end on this dang power steering. I have went thru everything 5 times and don't know where the issue is. Right when I start the tractor the pressure goes up for about 2 seconds then drops right off, like a relief valve is opening. Looking at my manual I see an "Auxillary Safety Valve" and it shows a plug on the bottom of block with spring and ball, but my does not have that. The is a plug but does not look removable. Is there some secret to finding this??

I can't help you with your question.

But I do know there are at least two 400/450 PS regulators/safety valves on eBay right now. Two different sellers.

Where are you checking the pressure, as this will make a difference as to the readings you are getting. If you are checking on the side of the valve in that test port your going up for a few seconds on start up would be normal. It is the regulator valve putting system on normal bypass pressures that I talked about before. When engine is shut off naturally the regulator ball will be seated so on start up pressure builds through the orfice screen, acts on the regulator piston that opens the ball. The relief valve on the bottom with spring and ball is the power steering relief valve and the only way you will read pressure of that valve is by hooking into the pressure port going to the steering motor. You can dead head test it or T into it but is easiest and best to dead head by taking the hose off to steering and putting a gauge directly into that port. If you don't get a good high pressure you know you have to work on the relief valve or flow divider. Most likely the flow divider unless spring is broken or some thing under the ball. If I remember correctly you can get that spring and seat out through the fitting opening under that same hose connection. Remember, it is only the relief valve for steering, main relief is that piston under the heavy spring under top four bolt cover.

I'm dead heading off the pressure line right before the PS motor. Also my flow divider valve is stuck "away" from the spring. That should give it the most pressure correct? How can I test if the relief valve is opening for sure? Is there away to clearify if it's the relief valve or flow divider?

By dead heading, I assume you mean the gauge is hooked in the end of the hose and hose is disconnected from the steering motor and that would be a good test. However, it is very hard to determine which one is problem except that if relief valve was leaking badly you would have low pressure to gauge even when dead heading one of the aux valves. I remembered how to get that relief valve out to check it, you need to take the spring and spool out of flow divider and go from underneath and screw it out. I would also be doing some other type of testing if me. I would hook a hose to pressure port to steering outlet, put a gauge in hose , then restrictor valve, run hose back to reservoir, close restrictor part way, and build some pressure, maybe couple hundred psi, pull hose out and time a flow into a container. Should get about three gallons per minute. Quart in 5 seconds. You have to make sure the gauge you have installed on there now is reading dead headed, blocked flow and not rely on turning steering wheel to block the flow as even a good unit will leak considerable oil through it and a worn or misadjusted gear end play in the unit will leak a lot through. If you can see wear on that spool of the flow divider it won't work, period. I have replaced many over the years after they made them a service item. Originally they were not.

Thanks for the reply Pete 23. Update from this morning. Took all of the regualtor, safety valve and flow divider out again, cleaned it all up installed it. Same thing. Only pressure for a second or 2 then drops off to nothing. I only see a plug that doesn't look like it can be removed on the bottom, is that just a cap or something? I'm assuming thats how it comes out.

No, it doesn't come out from that plug which is factory installed and not removable. You take out the fitting that power steering hose goes on, and go up through that hole to get the relief valve screw driver slotted seat out.

Yep got it. Looked like the ball was out of place but after I put it back togeter it did the same thing. Think i'm going to go back to manual steering. Thanks for everyones help on this!

Repair the divider valve! If it is stuck, the function may be compromized in a way that screws things up. I believe this is solvable. Jim