Toro kit for power steering on a 520h

[Damien Walker 288]

10 hours ago, ebinmaine said:

First things first. I want to say thank you for your effort and time putting these posts together. 

Whether I use any of these methods or not I'm really enjoying the information.  

Hi Eric...I've spent so.many years just lurking and not contributing that it is about time I did! I suffer from the heavy steering problem and decided to try to do something about it. I'm a little wordy perhaps but it's amazing how much there is in problems like this when you start to discuss them.

 

 

[Damien Walker 288]

10 hours ago, ebinmaine said:

First things first. I want to say thank you for your effort and time putting these posts together. 

Whether I use any of these methods or not I'm really enjoying the information.  

Hi Eric...I've spent so many years just lurking and not contributing that it is about time I did! I suffer from the heavy steering problem and decided to try to do something about it. I'm a little wordy perhaps but it's amazing how much there is in problems like this when you start to discuss them. Basically it's nice I've found something I feel I can add something to.

 

I agree, the absolute position of the wheel probably doesn't matter but it makes sense to try to keep it in the same position.

 

My problem with turns ratio stems from WH getting it about right...their steering is delightfully direct with an almost direct connection ...it's more like a bicycle as there is so little gearing as such....and the heavy steering stems from this fact. When I fitted power steering, it increased the turns ratio and whilst there was no effort involved, it was quite an effort to spin the wheel fast enough to avoid banging into things. I think the WH turns ratio is about right so we really only want to address the heaviness. Obviously with a geared solution, you can't achieve both so a compromise is required. 4:1 would be terrible unless your machine was very slow and not used for mowing I think. I'm concerned about your suggestion to use two quickeners...'one horizontal'...would that be in the main horizontal flag gear shaft? If you fitted a quickener there, yes it would reduce your steering effort but it would also halve the amount of steering travel ....which would not be a good idea!

 

As for the spline adaptor...yes, being GM, even over here, there must be tons of stuff available..in scrap yards if nowhere else!

 

Best of luck with Colossus...I'll try to keep a watch on your progress..it will be interesting to see how it develops.

[ebinmaine 72,231]

3 hours ago, Damien Walker said:

I'm concerned about your suggestion to use two quickeners...'one horizontal'...would that be in the main horizontal flag gear shaft? If you fitted a quickener there, yes it would reduce your steering effort but it would also halve the amount of steering travel ....which would not be a good idea!

 

 

That one would be fine. Reason being is I am REMOVING the Wheel Horse gears.

I need to put something more heavy duty and with as close to zero lash as I can.

 

I don't know what the actual factory gear ratio is for these tractors.

Somebody in the build thread mentioned that the fan to flag horizontal shaft rotates around a quarter turn so obviously that's what my steering wheel would also do if I just installed two or three u-joints to make the angle.

 

That wouldn't necessarily be completely unmanageable given the exercise of the steering wheel and the fact that I'm going to be running tri-rib tires with much higher than stock air pressure.

Still, I'd like to have some sort of division to the steering gears.

@Oldskool Mike showed me a link for something that would be used for an ice auger which is around 3.8, 4 to 1. That might work perfectly fine for my situation given consideration that I'm building the tractor one system at a time and I'm not trying to restrict myself to a given size or shape, within reason.

 

 

 

[Damien Walker 288]

All very interesting!

 

Removing WH's system would certainly give you more scope. My hydraulic conversion does the same in fact and the good thing is that the arguably difficult linkage is done with hoses which you can route anywhere.

 

I have considered a steering rack type system but finding one so narrow could be tricky. It might be possible to shorten one from something such as a VW Golf or a Smart 4-2. If you shorten the rack and the casing whilst aligning the input shaft to where the original horizontal flag shaft was, you could then connect that to the column via your fleet of ujs....steering effort must be much less than in the Golf due to the lack of weight.

 

I'm not sure whether mentioning a make of yellow tractors here is wise but some Club Cadets (ooer sorry folks!!!) have a sort of similar system to WH's in that they use a large geared quadrant which is pivotted on a cross shaft giving a forward and back motion which is linked to the wheels via a bell crank. I imagine the auger based idea might be a bit similar to this. I think a longitudinally operating quadrant like this might fit a WH chassis quite well and with the space available, increasing the diameter to reduce the effort might be do-able.

 

I look forward to seeing your machine in action.

 

[ebinmaine 72,231]

2 hours ago, Damien Walker said:

I look forward to seeing your machine in action.

 

ME TOO !!!

 

 

[WHDon 0]

Hi ,trying to get some more info on where to buy one of these power steering kits for my 520H. Any info would be great!

[Handy Don 13,884]

15 hours ago, WHDon said:

Hi ,trying to get some more info on where to buy one of these power steering kits for my 520H. Any info would be great!

I'm unaware of any “kits” for adding power steering to the 520. Damien adapted parts from other manufacturers and added some custom components to build his system. 

A couple of WH’s LX models had factory power steering, but they used a completely different frame, power train, and steering components not simply adaptable to the 520. 

 

As many have noted in this thread (and others), the 520 design squeezes a lot of machine into a small space. Modifications and extensions are not easy. 

Edited June 24 by Handy Don

[WHDon 0]

  I WANT P. S. For my 93  520 h .   WH DON

 

 

[Damien Walker 288]

Hello Don and Don! Yes, I fitted an orbital valve to my 518H (removing all of the oem 'flag' gear etc and adding minor bracketry). The 520H is near identical so to should be just as easy to modify....and the modification is excellent, the tractor is now amazing to drive. Apologies, I can't work out how to post a link to my threads on the subject (because I'm away from base and only have my mobile!) but search for 'power steering' on the forum and you should find them, including the document I wrote to show how it was done.

 

My orbital valve was very second hand (online auction house!), I bought the ram (£100) and fabricated the rest. If you want to give it a go, I'm very happy to discuss further. Sadly I'm not able to help directly due to being tge UK!

[Handy Don 13,884]

1 hour ago, Damien Walker said:

The 520H is near identical to the 518H

Important to note that the UK version 518-H used the Eaton 1100 transaxle while the US version 518-H used the 700 and a manual lift, i.e. no charge pump or other hydraulics. 

 

IMHO, finding and installing the Toro gear reduction steering hardware is less difficult than going to full power steering and probably less costly. Stock steering is one full turn lock-to-lock; reduction makes it two full turns--it isn’t as effortless as power steering, but it is close. The hardware needs only standard “grease gun” and simple tension adjustment maintenance. Toro brought it over from other products in their lineup to help when using heavy implements (e.g. loaders, 60” decks, two-stage blowers). 

[Damien Walker 288]

3 hours ago, Handy Don said:

Important to note that the UK version 518-H used the Eaton 1100 transaxle while the US version 518-H used the 700 and a manual lift, i.e. no charge pump or other hydraulics. 

 

IMHO, finding and installing the Toro gear reduction steering hardware is less difficult than going to full power steering and probably less costly. Stock steering is one full turn lock-to-lock; reduction makes it two full turns--it isn’t as effortless as power steering, but it is close. The hardware needs only standard “grease gun” and simple tension adjustment maintenance. Toro brought it over from other products in their lineup to help when using heavy implements (e.g. loaders, 60” decks, two-stage blowers). 

That's interesting Don! Unusual that US equipment in the UK was arguably a higher spec than that in the US🤔.

 

As far as I am aware, the 520 never made it over here, particularly with the forward swept axle. (I imported mine).

 

Even so, it would be fairly easy to add an automotive power steering pump and reservoir to provide the hydraulic power required. Some vehicles here have electric pumps but whether there's room to accommodate such a unit is difficult to say.

 

There are also electric power steering sets available but all the ones I have seen have the motor unit mounted perpendicularly to the steering shaft and there isn't sufficient room available to fit one, though it might be doable if you could find a small enough motor.

 

Finally, there's a thread on here somewhere where we were discussing other ways to implement a gear reduction, assuming the standard Toro parts were not available second hand.

 

Unfortunately, none of the above ideas are particularly easy to implement! If you could find a power steering valve to insert into the steering column, that would probably be the easiest to fit...provided your tractor has the Eaton 1100.

[Handy Don 13,884]

Another factor is balance when using parts from different systems. Using a “standard” cylinder means that extending the rod requires more fluid volume (and delivers higher force) than retracting the rod. If not offset, it will be much easier/faster to steer in one direction than the other. Many orbital valves automatically compensate for this (and require a specific size ram cylinder installed in a specific direction) but some require an external flow control.

Heavier machines with fully hydraulic steering (versus power-assisted mechanical steering) often use two ram cylinders (a left turn and a right turn) for balance. 

[Damien Walker 288]

9 hours ago, Handy Don said:

Another factor is balance when using parts from different systems. Using a “standard” cylinder means that extending the rod requires more fluid volume (and delivers higher force) than retracting the rod. If not offset, it will be much easier/faster to steer in one direction than the other. Many orbital valves automatically compensate for this (and require a specific size ram cylinder installed in a specific direction) but some require an external flow control.

Heavier machines with fully hydraulic steering (versus power-assisted mechanical steering) often use two ram cylinders (a left turn and a right turn) 

I have to admit that such complexities didn't occur to me when I assembled my system and I haven't noticed a difference between turning left or right. It's possible I suppose that my valve auto compensates, but I don't recall it doing that from the datasheet. It could also be that I haven't noticed the difference and if that's the case then I would file the problem under 'don't worry about it'. Next time I get the machine out, I'll do some careful steering and see if I can spot a difference. I changed the original 5xi ram I used to smaller one I had in stock because the turns ratio was too great when I first built it so paid no attention to ram sizing for this issue. I have a full JCB 3CX backhoe and that uses a double ended steering ram. I imagine a similar set up would be do-able (preferable in some ways too) on a Wheelhorse as it would remove the need for a track control rod.