Adding power steering and power beyond question.

[etpm]

I posted this in hydraulics but nobody replied so I am trying here.
I have a Yanmar YM2310. Last year I bought a hydraulic cylinder/valve combo made for adding power steering to this tractor. I got or made all the parts necessary to do the job except for the hose and some fittings. The project got put on hold for a while but now I once again have time to finish it. Before I order the hose and the rest of the fittings I would like some advice on plumbing.
The tractor has an aftermarket FEL and the valve for the FEL has power beyond. The hydraulic line that used to go directly to the 3PH was cut and now goes to the FEL valve. From the power beyond port on the valve a hose goes to the line that goes to the 3PH.
I have a flow divider and from that divider the fluid will flow to the power steering cylinder and to something else. The divider can be plumbed before the FEL valve. If plumbed that way the FEL and 3PH will be affected by the reduced flow. If the divider is plumbed after the FEL valve then only the 3PH will be affected. I think the latter scenario is the best way to plumb everything. I could be wrong though.
To maybe make things more clear I will restate things. The output from the hydraulic pump can go to the divider first. Then from the divider the pressurized fluid will go to the power steering cylinder and the FEL valve. Then from the FEL valve power beyond port the fluid will go to the 3PH. OR, the output from the pump can go to the FEL valve first, then from the power beyond port to the divider. Then fluid from the divider will go to the power steering cylinder and the 3PH.
If I plumb the diverter before the FEL it will mean less fluid to the FEL so it will move slower but the steering will work even if I am using the FEL. If I plumb the divider after the FEL the steering won't work if I am moving the FEL but the FEL will move as fast as it does now.
I can raise the engine RPM to compensate for the decrease in fluid if the divider is plumbed before the FEL. I don't usually use the FEL at top engine RPM anyway. Another way to compensate for reduced flow would be to buy and install a hydraulic pump with a larger displacement. However, I have not been able to find one that will fit my tractor.
Opinions?
Thanks,
Eric

 

[ericm979]

Does your loader valve send flow out the PB port when the valve is being operated? Mine doesn't, it all goes to tank. It'd be a bummer to lose power steering when you're moving the loader.

Will the divider always send flow to the steering even if the cylinder is not being moved? Maybe there is some sort of priority valve which will prioritize the steering but allow full flow to the loader when the steering does not need it? I think I'd rather have the loader performance vary than the steering but you might want it the other way.

 

[etpm]

Does your loader valve send flow out the PB port when the valve is being operated? Mine doesn't, it all goes to tank. It'd be a bummer to lose power steering when you're moving the loader.

Will the divider always send flow to the steering even if the cylinder is not being moved? Maybe there is some sort of priority valve which will prioritize the steering but allow full flow to the loader when the steering does not need it? I think I'd rather have the loader performance vary than the steering but you might want it the other way.

My FEL valve only sends fluid out the power beyond port when the valve is in the neutral position. I have decided to keep steering always and live with the slower FEL or higher engine RPM. You are correct, it would be a bummer to lose steering at any time.
Thanks,
Eric

 

[K5lwq]

Definitely put the divider before the loader. Does the divider you bought have adjustable flow rate for the priority circuit?

 

[rScotty]

Definitely put the divider before the loader. Does the divider you bought have adjustable flow rate for the priority circuit?

That is the way that Yanmar did it with their hydrostatic power steering. Before the FEL They used an adjustable divider with a priority circuit. Universal priority valves with adjustable percentage flow plus a relief valve are reasonably priced at hydraulic outlets like surpluscenter.com

I used to have the factory shop manual for the US versions of your tractor & I if I remember correctly it had instructions for setting the priority on the factory valve - which BTW, looks like any other priority valve. At full flow, roughly one third of full flow to the PS and the remainder to the loader. Lower flows prioritize to the the PS.

It was common on all those early tractors with priority & PS to lose some power to the steering at low rpm or when using the loader. No biggie. You get used to it or can raise the RPM to compensate. Most would probably rather suffer some loss of function rather than run an engine at full rated rpm all the time.

If what you have is an add-on power steering cylinder spliced into the steering drag link I expect it could be set up similarly. That form uses less fluid, but tends to leak. Still, it sure beats manual steerimg an FEL.

rScotty

 

[aczlan]

That is the way that Yanmar did it with their hydrostatic power steering. Before the FEL They used an adjustable divider with a priority circuit. Universal priority valves with adjustable percentage flow plus a relief valve are reasonably priced at hydraulic outlets like surpluscenter.com

I think that's how pretty much every OEM does it, they consider steering to be more important than loader movement.

Aaron Z

 

[pmsmechanic]

I Another way to compensate for reduced flow would be to buy and install a hydraulic pump with a larger displacement. However, I have not been able to find one that will fit my tractor.

The pump in the Yanmar in my 4410 has a tandem pump. One side is for the power steering and the other is for everything else. Would that be an option?

 

[etpm]

The pump in the Yanmar in my 4410 has a tandem pump. One side is for the power steering and the other is for everything else. Would that be an option?

I don't know. I like the idea of a tandem pump. I will try to find out if the pump for the 4410 will fit a YM2310. Is the 4410 a YM tractor?
Thanks,
Eric

 

[etpm]

Definitely put the divider before the loader. Does the divider you bought have adjustable flow rate for the priority circuit?

No, my divider is not adjustable, darn it. If I had known better I would not have bought it. If I have to I will buy an adjustable one. I hope I don't need to because I made a nice mounting plate for the one I have and the adjustable ones are quite different.
Thanks,
Eric

 

[etpm]

The pump in the Yanmar in my 4410 has a tandem pump. One side is for the power steering and the other is for everything else. Would that be an option?

The only 4410 I could find was a Deere that has a Yanmar engine. But all the pumps I found for that engine are not tandem. And, since my tractor is 20 years older I wonder if it would fit anyway if I could find one. Let's hope I don't need one.
Eric

 

[rScotty]

Tandem pumps are expensive. of course you can make adaprter plates and shaft connectors to run anything to anything, but why not just put a 15 gallon/minute accessory pump on the PTO shaft and run the whole tractor from it?
I'm afraid you will find that you need to have to have an adjustable divider. It also needs to have a dedicated relief valve.

I still think you are overthinking. People worked for many decades with power steering that wasn't expected to work well at low RPMs. It's really not as much of a problem as it is being made out to be. Some of the midrange priced cars when PS first came out had that problem at low RPMs. It made parking tricky sometimes.....

 

[California]

That tandem pump sounds like a great idea if you can fit it.

My little YM186D has the optional power steering from some vendor no longer in business. Steering works down to near zero rpm but the loader and 3-point are dead below 1,000 rpm. And are slow at that RPM. This is a nuisance.

In particular backing up on rough ground to get rear forks under a pallet, or to align the quick hitch to a parked implement. You want slow ground speed and quick 3-point height adjustment but the engine has to be well above slow idle to control the 3-point.

Front loader similar, ram into a gravel pile and as the engine slows you can't lift or curl the bucket.

Power steering is great but the more limited hydraulic function is a noticeable compromise.

 

[ptsg]

If it was me, I would simply add another pump, either belt driven or crankshaft driven (mounted right in front of the engine). Sure it will require some more fabrication and (maybe) an extra reservoir but it would always have steering and loader functions. Another solution could be using one of those power steering pumps with the reservoir built in from a vehicle of some sort.

 

[etpm]

If it was me, I would simply add another pump, either belt driven or crankshaft driven (mounted right in front of the engine). Sure it will require some more fabrication and (maybe) an extra reservoir but it would always have steering and loader functions. Another solution could be using one of those power steering pumps with the reservoir built in from a vehicle of some sort.

My first inclination was to use a power steering pump from a car. I even got myself a pump. The problem was driving the pump. There is no easy was on my tractor to take power from the engine to power a pump. A big reason is because of the front end loader. The mounting structure is in the way. There is a special pulley on the front of the engine made for connecting something. I am not sure what though. In any case the space in front of the pulley is blocked. I am sure I am over thinking the whole business. It's just that I want the power steering installed and I don't want to have to do things over. To install the cylinder and associated hardware I will need to take stuff apart. And, of course, the tractor will be unusable until the installation is done.
Eric

 

[rScotty]

Some mid 80s vintage US Yanmars ran the FEL or accessory hydraulics via a small pump driven by a shaft that extended forward from the front of the crankshaft pulley. Connection was by a flexible shaft to shaft connector. You might look to see if your crankshaft pulley has a couple of threaded mounting holes in the front face.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

The Yanmar pump used was about 5 GPM and was mounted in line with the crankshaft. Of course any type of pump could be used. An automotive one would be overkill, but why not?

We had a Yanmar with loader and manual steering for 35 years. Power steering would have been so nice I would not have cared what compromises it caused. As it was, I would lower the bucket to the ground, lift the front, turn the wheels, and repeat. I'm sure you know the drill.

 

[pmsmechanic]

The only 4410 I could find was a Deere that has a Yanmar engine. But all the pumps I found for that engine are not tandem. And, since my tractor is 20 years older I wonder if it would fit anyway if I could find one. Let's hope I don't need one.
Eric

John Deere uses almost exclusively Yanmar engines in their compacts, subcompacts and self propelled mowers etc. I'll bet the tandem pump in my 4410 is a John Deere only part.

 

[etpm]

Some mid 80s vintage US Yanmars ran the FEL or accessory hydraulics via a small pump driven by a shaft that extended forward from the front of the crankshaft pulley. Connection was by a flexible shaft to shaft connector. You might look to see if your crankshaft pulley has a couple of threaded mounting holes in the front face.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

The Yanmar pump used was about 5 GPM and was mounted in line with the crankshaft. Of course any type of pump could be used. An automotive one would be overkill, but why not?

We had a Yanmar with loader and manual steering for 35 years. Power steering would have been so nice I would not have cared what compromises it caused. As it was, I would lower the bucket to the ground, lift the front, turn the wheels, and repeat. I'm sure you know the drill.

Do you have a picture of this setup? Or do you know where I might find one? My tractor does have a weird front pulley. I believe it has two tapped holes. It is very hard to see the front of the pulley so I can't say for sure. From what I can see and feel there are two bosses and these appear to be tapped.
Eric

 

[California]

The Yanmar-US YM240 Parts manual shows a front PTO option that is a raised battery platform and a shaft with bearings. Here's the thread where it was discussed. Maybe fabricate something similar?

 

[etpm]

The Yanmar-US YM240 Parts manual shows a front PTO option that is a raised battery platform and a shaft with bearings. Here's the thread where it was discussed. Maybe fabricate something similar?

Thanks for posting this info and the link. I never thought about raising the battery platform. The power steering pump I got some time ago is from a Honda car, I think a Civic. It rotates in the direction opposite to most power steering pumps. This means that it could be driven from the end of the engine and facing the engine. Now I'm really pumped (get it? pumped? yeah, bad joke, I know) about using that power steering pump again. Time to take a look at the front of my YM2310 again to see if this could work. If I can make this work it might mess up my plans a little though because adding the power steering pump may involve fabricating parts that require machine work and welding. As I started getting all the things together to put power steering on my tractor I decided to try to use stuff that would make it possible for someone to do the conversion with only a 1/2 inch drill motor or a drill press. I have been taking pictures and I have a list of parts purchased so I can post the whole mess here. And a big bonus is that the original drag link is kept as a spare part instead of modifying it like the original instructions say to do. This way if the power steering unit fails it can be removed and the old drag link put back in place.
Eric

 

[aczlan]

A couple of pictures of how the front pump was setup on a David Brown that I had for a while.

The shiny bolts at the bottom of the radiator in this picture are where the driveshaft was bolted to the crank pulley:

Overall view of the pump in place:

The misalignment coupling on the pump:

Thought I had one of the pump driveshaft, but I dont see it.
IIRC the flange that bolted to the crank pulley looked sort of like this: McMaster-Carr

Aaron Z