D-200: Whet is feed and return from pump?

[Ian928 46]

I am posting this question here, hoping for someone to be able to help me (this question is also posted in the Modifications forum.)

In short we are fitting a hydraulic steering valve to our D-200 and need to connect in series before the lift valves. I am a little confused because it seems the return from the valves are going back into the pump? See the pictures below, I belive A or B in the photo is pressure and return? I have also included the parts drawing from the Toro page, both lines are described there as pressure lines (14 and 15). Can they both be delivering pressure? In that case I can not see any return, C and D are for cylinder 1 and E and F are for cylinder 2.

Does anybody have any experience with this? And if not, what should I do, start the tractor and loosen the connections while operating the cylinder to see which one leaks?

[Operator 7]

I do beleive that #14 is pressure in and #15 is return.

Randy

[jerrell 1]

:whistle: wouldn'tt they both be pressure in and return,looks like the pressure goes in on one end and forces the piston out and when you move the control, the pressure is on the other end forcing the piston closed, i really don't know but someone with more knowledge than me will be on here with more info :thumbs:

[Operator 7]

Presure comes from pump all the time then when you move lever that deverts oil to the lift ram for up or down but when levers are in neutral oil is going thru vale body and out the return side back to res. How does that sound?

Randy

[Ian928 46]

I do beleive that #14 is pressure in and #15 is return.

Randy

This is really what I am looking for. how can I be sure? Maybe just remove the lines and turn the pump over? I believe that if I put pressure up the return line I will damage the steering valve... :thumbs:

[Operator 7]

#15 is press. it goes to the releif valve,#14 is the "return" line. Keep in mind that you may not be able to do two things at the same time "steer" and "lift" you will be starving one side or the other.I've hooked up truck snowplows this way using the power steering pump it works but when I "lifted" I couldn't steer.

Randy

[Ian928 46]

#15 is press. it goes to the releif valve,#14 is the "return" line. Keep in mind that you may not be able to do two things at the same time "steer" and "lift" you will be starving one side or the other.I've hooked up truck snowplows this way using the power steering pump it works but when I "lifted" I couldn't steer.

Randy

Thank you very much!

We will at connct the steering valve in front of the lift valves so that the steering will have priority! It may be a pain not to be able to lift the snowblade when steering, but compared to the way it is now it have to be a change to the better: Trying to operate the lift valve with the left hand while operating forward/back + throttle (the governor was disconnected by the PO) with the the right hand, and at the same time needing both hands to turn the steering wheel!

And at the same time my feet does nothing... I rarely(never) use the brake because the hydro is brake good enough. I wish I could operate the lift cylinder with pedals on the left foot and forward/back movement with pedals on the right foot.

[Ian928 46]

Hmmm... The return line, is that really a no pressure line in this application? If not, I need to create a separate return line from the steering valve. My initial plan was to put a T-piece on the return line, but for that to work it should not be pressurized. Is it correct that the "return" line is used to feed the hydrodrive part of the pump and if that is true is the pressure in this line near zero??

[Operator 7]

I'm kind of shooting from the hip on this one but my thinking is it doesn't really feed the hydro drive because on some of the tractors there is no hyd. lift the ports are plugged off, I'm one to experiment and I would try the tee. What you think? sound like an idea? I wont be checking the computer till this evening right now it is noon and I'm in for lunch. Hopefully I'm some kind of help. I've plumbed up a lot of hyd. things but I'm not that familar with the WH pump set up.

[Ian928 46]

I'm kind of shooting from the hip on this one but my thinking is it doesn't really feed the hydro drive because on some of the tractors there is no hyd. lift the ports are plugged off, I'm one to experiment and I would try the tee. What you think? sound like an idea? I wont be checking the computer till this evening right now it is noon and I'm in for lunch. Hopefully I'm some kind of help. I've plumbed up a lot of hyd. things but I'm not that familar with the WH pump set up.

I won't finish this until after the next weekend because I am not able to get the lines made until that time. I will probably go for a T though, I am thinking that if there is pressure in that port it will at least not be as much as in the feed or else the cylinder would not move! I am guessing the steering valve probably can handle some bakpressure also?

You are very helpful thank you!

[Operator 7]

Good plan Ian, The tee should work with no real problems. Fluid just passes thru unless diverted thru valves and out to the resavore {the hyd. unit} the path of least resistance. I'll be watching.

Randy

[Ian928 46]

Ok, we have now completed the installation, and the first impression is.... not good!

The steering is very heavy and it does not seem to differ if we increase rpms or if the tractor is moving or standing still.

I have made a scetch of how we have connected the cylinder. Have we done anything wrong? For reference, the drawing is based on the picture I posted earlier, so OUT from the Hydro unoit on the scetch equals A on the picture and RET equals B on the picture.

[Operator 7]

I've been waiting to see how you turned out. Diagram looks right. Does the lift work with a load on it? Turn ram- did you"bleed" air out? Both directions. Worst come to worst could you hook up separate pump for steering?

Randy

[Ian928 46]

I've been waiting to see how you turned out. Diagram looks right. Does the lift work with a load on it? Turn ram- did you"bleed" air out? Both directions. Worst come to worst could you hook up separate pump for steering?

Randy

We did not test it completely today, we have not tried the lift cylinder yet, maybe that will tell us more (if it don't work we know there is something wrong)

It may be that the supplied pressure is not high enough, but my first impression is that it did not matter much if the pump was running or not. Also, it was very heavy turning the wheel even when the cylinder was not connected to anything. We bled the cylinder before installing it (we had to mount it with the connections downwards).

Is it possible that you were wrong Randy, and that we have switched pressure and return? When I turned the wheel with the engine off I could hear that after some turns air entered the system.

[Operator 7]

I've been wrong before but the press. line shold be the one that is going to the relief valve . What I can do is check some pumps and valves I have in the shop on monday. Could you just switch the lines easy enough? to check. I've had some power assist steering on early Ford trucks and once you took the valve apart and back together then started the truck it would turn the wheel by itself to the right and stay there. Bad system. I'll check my pumps.

Randy

[Operator 7]

:thumbs: Ian I was wrong! The feed and return are backwards, Sorry. The press. releif is after the cyl. valves, so if your trying to pick up something

to heavy the press. releif pops open and more oil gets bypassed to return. If it goes to releif first then valves and you try to pick heavy the releif valve wouldn't have anywhere to "dump" oil. So yes I WAS WRONG. Switch the two lines "feed" and "return". The only other problem I see the tractor pump "may" not have enough pressure but even that would just make it slow. Maybe the steering system will need it's own pump, then you can run implements and steer at the same time.

Randy

[Ian928 46]

Randy, no hard feelings! The lines are interchangeable so this is just good news for me (it means we probably can get this to work)

I have been running this discussion in two threads now, maybe it's time to pull them together, would you please look under Modifications and Chassis Modifications in the thread Power Steering? I have asked a question about a power relief valve there, I would be very gratful if you would answer in that thread!

[Ian928 46]

Today we switched ports, aaaaaaaaaaaaaand success!!

It is like driving a different tractor, we can now steer one-handed with the steering ball like nothing at all. Also gone is the slack in the steering from the old steering box and all the joints leading to the wheels. I can really recommend this for other owners of D-series tractors out there! I am looking forward to the next snowfall now!

to everybody that helped us along, especially Randy and Mith!

I will take some pictures of brackets and lines and so on and post as a reference here for anybody wishing to do something similar.

[Operator 7]

I'll leave a note here too. Glad it worked Ian, Sorry for the mix up on lines.

Randy