What's new

Steering Reservoir Tech (and Demo)

I have friends who have blown off 5000PSI rated hoses with a non-reactive valve.

I'm a big fan of non-reactive valves, the driver fatigue side of it is part of it, wheel kickback is a thing, but especially for crawling, my opinion is that non-reactive valves are immensely easier on pumps than reactive valves. With a reactive valve, you have to hold the wheel where you want it, and the pump has to be supplying pressure to do that, any time the wheels want to go somewhere you don't want. With a non-reactive valve, you put the wheels where you want, and leave them there until you want to change them, and the valve does all the "work" by refusing to flow back through, all while the pump is just idling, and can cool off. As such, I honestly believe one of the biggest killers of pumps in our niche of the offroad world, is our collective push to use reactive valves. Correspondingly, I believe cooler sizing needs to be dramatically bigger for a hydro system using a reactive valve, than what can be "gotten away with" if it's built with a non-reactive valve.

As to the blowing off of hoses, one of the bits that we typically leave out, is work line relief valves. If you look at how a road grader, scraper, front end loader, or any other big hydraulic steered machine is set up, they have relief valves to prevent exactly that. Not saying we "should" leave them out, but "should" or not, we typically do.

And yes, I'm aware that for some things, a reactive valve is necessary, if you want to flat-tow something with hydro steering, you'd better have a reactive valve. Road driving it is easier with a reactive valve. Ease of handoff to somebody who doesn't know how to drive it, is much smoother with a reactive valve. I generally give a couple pointers to somebody who's never driven my rig before; one of those is "don't crush my steering, it'll go, or it won't, but if you can't palm the wheel to where you want, pulling harder on the wheel won't change things, move the car a little and try again".

For a trip through the wayback machine, those who remember my vehicular gymnastics at the WERock in Boyd TX... I didn't blow any hydro lines, but I did twist a rear high steer arm (kingpin 60 arm, 3/4" thick, about 2.5" wide) in the process of those two barrel rolls and a most-of backflip. Work line relief valves would have prevented that damage, but "it wasn't that bad".
 
For a trip through the wayback machine, those who remember my vehicular gymnastics at the WERock in Boyd TX... I didn't blow any hydro lines, but I did twist a rear high steer arm (kingpin 60 arm, 3/4" thick, about 2.5" wide) in the process of those two barrel rolls and a most-of backflip. Work line relief valves would have prevented that damage, but "it wasn't that bad".

 
Interesting

My understanding is that the cylinder to valve lines are T'd into the two accumulators. Not the pressure or return lines on the valve or pump. One for left, one for right. The pressure is set at 460PSI. The DSC normally adds compression valving on entering fluid and free flows on return. With 460PSI keeping the oil out of the accumulator. There is no oil bypassing into the accumulators while steering with light force. When the force from an impact to the tires spikes the pressure, the oil will flow through the DSC burning up energy and dampening the tire movement, the oil will then flow into the accumulator to allow the tires to turn and react to the terrain, eventually the pressure will build high enough in the accumulator and equal the force at the tires and when the force at the tires is gone or has past the accumulator will push out the oil and move the tires back into the position.
This will create a cushion as well as slop between the tires and the steering wheel under high force when used in the rocks when the steering system is seeing high pressure. When going high speed when light steering input is needed, the 460PSI is high enough that the accumulators will not be functional and there will be no slop or cushion. Both of the applications mentioned are on trophy trucks, not rock racers. I am interested how the system performs at slow speed in the rocks and if it is still useful or if the slop is too great.

I used a similar form to this function on my old hydraulic buggy. The part is called a cross port relief valve. When the tires see an impact that creates a pressure spike the oil will dump over a relief valve burning up energy and fill the other side of the cylinder. This creates the same cushion and dampening effect. The difference is the cylinder can bypass all the way from left to right and there is no accumulator to max out and go solid. So you have more dampening. The pressure relief valves in the cross port relief block can be adjusted to crack at higher pressure than the 460 PSI so they would not open and create slop unless you really hit something hard, then with the higher pressure and unlimited flow they could burn up more energy through dampening.
The accumulator style keeps the oil on one side of the cylinder so if you hold the steering wheel straight the tires will move and return to center. The cross port relief style moves the oil from one side to the other side of the cylinder so if you hold the steering wheel straight the tires will move and you will have to turn the steering wheel to center up the tires after the impact.
It would be one of those things that is up to the drivers feel on how it performed. On my new buggy I did not feel like it was worth it to plumb in a cross port relief. It is very easy to add if I feel like I am crashing into rocks all the time and need a cushion, but I don't think I will be driving that way.
One thing to add is that a cross port relief if a good safety device to limit line pressure so hoses, orbitals, and cylinders do not burst. I believe that some have blown up the Sweet steering valves from over pressuring due to wheel impacts. So there is a known need in racing to cushion the impacts with some sort of energy absorption.
 
If you figured out what your pressure was in your system while idle, not turning, the back pressure is likely 150-200 psi.
mid you set a small accumulator at say 25psi, and it fills to 150psi, it could take up some slack in throttle lifts. Not much pressure, but flow yes. Even with open Center.
while racing your mostly going to be coming off 3500 or so rpm, 1 maybe two saws at the wheel, then back to WOT. It could make some difference. But the unpredictable nature of once it’s out, then it gets stiff, would concern me.
probably need to place a check valve between pump and any sort of accumulator

1 guy responded and said they are running ~450psi in the charge.

it sounds like they are using it solely as a steering damper
 
For a trip through the wayback machine, those who remember my vehicular gymnastics at the WERock in Boyd TX... I didn't blow any hydro lines, but I did twist a rear high steer arm (kingpin 60 arm, 3/4" thick, about 2.5" wide) in the process of those two barrel rolls and a most-of backflip. Work line relief valves would have prevented that damage, but "it wasn't that bad".

In my case, it has to deal with rockbouncers. They enter those rocks at a rate of speed that's really rough on components sometimes.

Seems like the PSS accumulator won't help that problem. Working line pressure reliefs are likely the answer.
 
In my case, it has to deal with rockbouncers. They enter those rocks at a rate of speed that's really rough on components sometimes.

Seems like the PSS accumulator won't help that problem. Working line pressure reliefs are likely the answer.

I would say yes, working line relief would be a good idea in that case. If you're running balanced systems, you can crossport-relieve like HD noted, where your relief on one cylinder line goes to the other cylinder line; if you're running unbalanced, I would think things get a bit more complicated as you'd need to relieve to reservoir and also probably need to include a check valve for a vacuum breaker on each line as well.
 
I would say yes, working line relief would be a good idea in that case. If you're running balanced systems, you can crossport-relieve like HD noted, where your relief on one cylinder line goes to the other cylinder line; if you're running unbalanced, I would think things get a bit more complicated as you'd need to relieve to reservoir and also probably need to include a check valve for a vacuum breaker on each line as well.

Balanced system, yes.
Got a link / pic for a crossport relief valve ?
 
The aluminum block is a cross port relief body. It has two straight through parallel ports. The two ports are connected by a relief valve only going one way to dump pressure into the other passage way. I am only using one relief valve in the body as the other port is low pressure return. I used it to streamline plumbing rather ran running T's or multiple fittings.

You can put multiple cartridge's into a cross port relief so you need to make sure the cartridge is designed for cross port use. The particular one I used is not rated for cross port, but that is fine because it is only being used as normal relief valve. HydraForce is who makes my parts. They have a really good website. It should be listed under pressure relief valves.

As you can see it is really easy to install inline. Cut your lines, add some more hose ends and bolt it up to some tabs and that's it.
Make sure you are using a high flow cartridge so you can flow as the tires can move faster than the pump can flow. I want to say the one pictured is rated around 30GPM. Some are only good to 10 GPM and you can over pressurize your lines with a hard hit as the fluid can not move fast enough. Still better than nothing at all but if you are doing it do it right.
fetch
 
Last edited:
The aluminum block is a cross port relief body. It has two straight through parallel ports. The two ports are connected by a relief valve only going one way to dump pressure into the other passage way. I am only using one relief valve in the body as the other port is low pressure return. I used it to streamline plumbing rather ran running T's or multiple fittings.

how is what you have different the what howe/psc offer?

HOW-2251101-Exter-reliefValve_800x600.jpg
 
Why aren't you running cross port relief for the cylinder hoses? That looks like pressure relief for the line from the pump to the orbital? What is that accomplishing? Doesn't the pump already have a pressure relief inside the flow control valve?
 
Why aren't you running cross port relief for the cylinder hoses? That looks like pressure relief for the line from the pump to the orbital? What is that accomplishing? Doesn't the pump already have a pressure relief inside the flow control valve?

relief between the pump and the steering valve prevents large spikes from blowing up the pump, which can happen if you are relying on the internal (small volume) pump relief that just loops back inside itself.

if you are using a non-regulated pump, then it is required to keep the pump from trying to add pressure to a spike and grenading itself that way.

big, or only, concern with a cross cylinder relief port would be a large hit at high speed turning your tires in (or out) when you don't want or expect them to, and now you'd need to react with steering wheel input that may or may not happen in time.

obviously if something blows up then you've found your limit. set your relief "too high" and something may blow up anyways.
 
how is what you have different the what howe/psc offer?

The Howe one just has their own aluminum block with their name on it and it is pre set at 1600 PSI also $265
You can find Hydraforce on ebay and surplus dealers for $100 for the same thing. But you have to look up the part numbers to know what you are needing.

My cartridge has a higher flow rating based just on looks of the size they use, its looks like they use a smaller cartridge body size.
Howe uses a T for the return and a dead end for the pressure so you need a another T on your pressure line somewhere else to connect to the relief. Their T also looks like it is only -8 where the cross port fittings are -12. The cross port housing runs the pressure inline and the return inline to minimize the use of T's. What is hard to see is there is a T at the orbital since that is where the relief oil meets the orbital return oil as it enters the cooler line so everything gets cooled before returning to the pump.
 
Why aren't you running cross port relief for the cylinder hoses? That looks like pressure relief for the line from the pump to the orbital? What is that accomplishing? Doesn't the pump already have a pressure relief inside the flow control valve?

My pump is a non regulated so I need to run an external relief valve between the pump and the orbital. I am also running a check between the two but after the relief to protect the pump from back feeding when hitting something at speed.
 
relief between the pump and the steering valve prevents large spikes from blowing up the pump, which can happen if you are relying on the internal (small volume) pump relief that just loops back inside itself.

if you are using a non-regulated pump, then it is required to keep the pump from trying to add pressure to a spike and grenading itself that way.

big, or only, concern with a cross cylinder relief port would be a large hit at high speed turning your tires in (or out) when you don't want or expect them to, and now you'd need to react with steering wheel input that may or may not happen in time.

obviously if something blows up then you've found your limit. set your relief "too high" and something may blow up anyways.

The safest way to set the cross port relief would be to set the pressure to match the hose rating so the hose will not blow out. Granted most hoses are rated 4 times for actual burst pressure. Average hose working pressure would somewhere around 3000 PSI which is nearing the rating of aluminum bodies. I would guess that Sweet valves are even lower pressure rated and if the Sweet valve blows up then your steering is probably a lot worse than having the cylinder bypass a little.
If your steering mechanically breaks then that is also a lot worse than a cylinder bypass.
If you are dropping pressure down for comfort when hitting obstacles then you nearing the point of loosing control of the cylinder too often while not having the pressure high enough to burn up energy for a hard hit. Without burning up the energy at high pressure the cylinder will move too easy and the mechanical stops will take the full hit and possibly break.
 
The safest way to set the cross port relief would be to set the pressure to match the hose rating so the hose will not blow out. Granted most hoses are rated 4 times for actual burst pressure. Average hose working pressure would somewhere around 3000 PSI which is nearing the rating of aluminum bodies. I would guess that Sweet valves are even lower pressure rated and if the Sweet valve blows up then your steering is probably a lot worse than having the cylinder bypass a little.
If your steering mechanically breaks then that is also a lot worse than a cylinder bypass.
If you are dropping pressure down for comfort when hitting obstacles then you nearing the point of loosing control of the cylinder too often while not having the pressure high enough to burn up energy for a hard hit. Without burning up the energy at high pressure the cylinder will move too easy and the mechanical stops will take the full hit and possibly break.

that second part is what seems concerning about a 450 psi damp on the cylinder. granted, the pressure would go up substantially with little volume, it just doesn't seem like the best solution from a predictability standpoint
 
Bringing this thread back up to the top, I finally had a chance to run my comparison demo on a reservoir with integrated spin-on filter. The difference is pretty staggering in terms of fluid circulation and air removal. I won't say that you should not consider a reservoir with filter combo but if you do, be prepared to spend some time trying to get the system properly bled of air.

 
Soooo, basically there's no need to bleed a system with your resi? Just plumb everything, add fluid and run the pump until it's done?
 
Soooo, basically there's no need to bleed a system with your resi? Just plumb everything, add fluid and run the pump until it's ready ?
Disclosure: I don't have his res. I don't have his system. I do have a (smaller) reservoir using a lot of the same separation dynamics, and I have two pumps feeding off of one res.

When I put what I have, together on my current engine, I hooked it all up, put fluid in, and left the belt off. I power-drill-spun one pump and had my kid cycle the wheel a few times to stuff fluid into the front end. I had her cycle the rear steer a few times to put fluid into the rear steer. I topped up the reservoir, put the belt on, and started the engine. I did not further bleed the system after that. It didn't need it. I topped up the fluid a couple times over the next month or so.
 
Correct, you still need to be methodical about the process especially when filling the system for the first time but the process Scott described is all it takes. The pump should be spun slowly to initially fill the system and as he did, a hand drill is ideal for this purpose if you can get one in front of the pump. Make sure to keep the reservoir topped off while the system gets filled and you should be good to go after that.
 
How about running the fluid through the filter first back to the reservoir? Like a Canton style filter.
That's how I normally setup systems is with a remote mounted filter inline between the orbital or steering box and the reservoir return port. By doing this, I can let the filter do it's job of solids contamination removal and let the vortex reservoir do its job of de-aeration and fluid circulation.
 
Soooo, basically there's no need to bleed a system with your resi? Just plumb everything, add fluid and run the pump until it's done?

there was a few years back where miller swapped a pump at the last pit for the finish, make sense now how they can swap the pump and not have any issues. swap pump, dump fluid, peel out.
 
there was a few years back where miller swapped a pump at the last pit for the finish, make sense now how they can swap the pump and not have any issues. swap pump, dump fluid, peel out.
Miller is sponsored by Howe I think.
Last time I checked (June this year at AOP) he was running their resi.
They hot swapped a pump again during the race there. Cost them 15mn and the win.

I think that Josh Blyler has all Radial Dynamics stuff on his car and was super happy about it when we talked.
 
Correct, you still need to be methodical about the process especially when filling the system for the first time but the process Scott described is all it takes. The pump should be spun slowly to initially fill the system and as he did, a hand drill is ideal for this purpose if you can get one in front of the pump. Make sure to keep the reservoir topped off while the system gets filled and you should be good to go after that.

I can't put a drill in front of my pump but I take a small belt and run it around the drum of the drill (it acts like a pulley) and run it for a while.


You're making it hard not to buy your fancy resi :flipoff2:

PS : The pump arrived yesterday and it's badass. I'm excited :grinpimp:
 
Top Back Refresh