Steering Reservoir Tech (and Demo)

[DesertCJ]

That outlet you are talking about is tuning the bypass valve. There are consequences to drilling it out. Have a look at the CBR thread as mentioned.

OK, I'm reading through all 12 pages. In the meantime maybe you can just let me know what the consequences are? Pretty sure, I'm reading that drilling out the output basically increases the point of flow where the pump bypasses internally? And if it's bypassing internally, the pump is eating hot oil(Bad)? I'm sure I'm missing something or more than one thing but what are the downsides to this?

 

[HYDRODYNAMIC]

"I didn't even try to look it up" realm) out of my wheelhouse cost-wise

When you are digging up the Titanic or preventing the next Deepwater Horizon you don't need to know how much parts cost. That accountings job.

 

[HYDRODYNAMIC]

OK, I'm reading through all 12 pages. In the meantime maybe you can just let me know what the consequences are? Pretty sure, I'm reading that drilling out the output basically increases the point of flow where the pump bypasses internally? And if it's bypassing internally, the pump is eating hot oil(Bad)? I'm sure I'm missing something or more than one thing but what are the downsides to this?

The pump will end up sending out more oil and bypass less. This can lead to too much flow in a restrictive system downstream of the pump, building heat and over pressurizing a system designed for a lower flow rate. The excessive flow can also make the steering more reactive at higher engine speeds and higher vehicle speeds creating a more twitchy steering wheel feel. Some pumps are not ported to full flow they need to bypass to keep oil in the pump or they will cavitate as they can not get the extra flow in and out.

 

[rockyota83]

hes not selling it to the guys who are drilling out reman pumps from autozone.

you just repeated what i said only in different words

 

[RadialDynamics]

Early on in my reservoir obsession I spent many hours brainstorming floating pistons, diaphragms, etc. but there were many reasons that I ultimately decided that a sealed system was not the answer.

First of all, pressurizing the reservoir absolutely helps reduce cavitation. This was actually the very first tech demo I published when I launched two years ago (to jump to the demo, go to 1:50):


The point that I always need to warn when people see this video is that yes, a pressurized reservoir reduces cavitation but there IS A LIMIT! The pump shaft seal is exposed to the reservoir pressure minus losses. Above typically 20 PSI you risk damaging that seal (I have actually popped a seal out on my test bench by accident while experimenting). This is why I now run 10 PSI caps on my reservoirs for safety factor when it comes to the seal.

So back to a sealed system, if one were to use a piston or diaphragm and wants to keep cavitation to a minimum, you need a way to maintain that 10 PSI while the fill level rises and drops due to thermal expansion and shaft displacement. In shock reservoirs which is what I have had many people pitch before, we are talking far greater pressures and pressure swings due to shock shaft displacement which the pump shaft can't handle. The other thing was that in races, leaks can develop, mechanics may need to open the reservoir for a multitude of reasons. Ultimately, I decided that if I could develop a reservoir that performed the way this one does, then any kind of sealed system would only make maintenance more time consuming and increase part complexity and cost.

Yes, I know that are not in everybody's budget although even in the recreational crowd, I've spoken to many folks that have gone through pump after pump in the past. The 4" model is for the higher flow TT and non-regulated industrial or race pumps. Most pumps are under 6 GPM regulated flow for which I recommend my 3.5" diameter model which is $545 and it really only takes one prevented pump failure to make up the difference above a "standard" reservoir (not to mention the inconvenience of a failed pump in the middle of a trail).

All in all, this design has had an impressive track record of success over the past few years between Ultra4, Monster Jam, and yes, many recreational customers.

 

[rockyota83]

. I can't use his (I need dual outlets) .

fwiw he builds custom units which most likely could be had in a dual outlet configuration

I do like that he's willing to show and talk about (at least a good bit of) the tech bits in there, 'cause guys like me will poach tech and put it in our lowbuck DIY junk too.

i agree 100%

 

[mobil1syn]

you just repeated what i said only in different words

there are plenty of recreational guys who want stuff to work and dont mind paying for it. people have no problem throwing down for a full hydro system from howe, psc, etc. because its a system with components designed to work together.

the guys using off the shelf pump, surplus rams and orbitals mixing up parts and hoping for the best. 60% of the time it works, the other 40% is misery.

i had a front row seat to someone trying to do what ScottRS did with his dual pump setup, even with a lot of input from Scott. lots of money, waling and gnashing of teeth. for what he was doing dual pumps was not needed looking back. a howe full hydro system would have done everything he wanted and then some in a simple package.

 

[DesertCJ]

hes not selling it to the guys who are drilling out reman pumps from autozone.

And amazingly, my drilled out autozone pump works great and I have 0 problems with my hydraulic steering. Ironic...lol

 

[DesertCJ]

Early on in my reservoir obsession I spent many hours brainstorming floating pistons, diaphragms, etc. but there were many reasons that I ultimately decided that a sealed system was not the answer.

First of all, pressurizing the reservoir absolutely helps reduce cavitation. This was actually the very first tech demo I published when I launched two years ago (to jump to the demo, go to 1:50):


The point that I always need to warn when people see this video is that yes, a pressurized reservoir reduces cavitation but there IS A LIMIT! The pump shaft seal is exposed to the reservoir pressure minus losses. Above typically 20 PSI you risk damaging that seal (I have actually popped a seal out on my test bench by accident while experimenting). This is why I now run 10 PSI caps on my reservoirs for safety factor when it comes to the seal.

So back to a sealed system, if one were to use a piston or diaphragm and wants to keep cavitation to a minimum, you need a way to maintain that 10 PSI while the fill level rises and drops due to thermal expansion and shaft displacement. In shock reservoirs which is what I have had many people pitch before, we are talking far greater pressures and pressure swings due to shock shaft displacement which the pump shaft can't handle. The other thing was that in races, leaks can develop, mechanics may need to open the reservoir for a multitude of reasons. Ultimately, I decided that if I could develop a reservoir that performed the way this one does, then any kind of sealed system would only make maintenance more time consuming and increase part complexity and cost.

Yes, I know that are not in everybody's budget although even in the recreational crowd, I've spoken to many folks that have gone through pump after pump in the past. The 4" model is for the higher flow TT and non-regulated industrial or race pumps. Most pumps are under 6 GPM regulated flow for which I recommend my 3.5" diameter model which is $545 and it really only takes one prevented pump failure to make up the difference above a "standard" reservoir (not to mention the inconvenience of a failed pump in the middle of a trail).

All in all, this design has had an impressive track record of success over the past few years between Ultra4, Monster Jam, and yes, many recreational customers.

That's awesome. Now I might just replace the vent in my reservoir with a shrader and throw like 5psi in there.

 

[arse_sidewards]

That's awesome. Now I might just replace the vent in my reservoir with a shrader and throw like 5psi in there.

Junkyard brass radiator, cut the cap area off and braze it on to your reservoir and run a low pressure radiator cap instead of whatever cap you were running before.

 

[RadialDynamics]

That's awesome. Now I might just replace the vent in my reservoir with a shrader and throw like 5psi in there.

Not recommended. As fluid heats up, it will expand and potentially overpressure that pump shaft seal since the schrader won't do anything to limit pressure like a radiator cap will. The radiator cap vents just enough air as the fluid heats up and expands to limit pressure. I put a schrader valve on my monster truck reservoirs so that they can pre-charge before a show since they will typically be starting cold but this is separate from the cap which will still limit the pressure.

I just recently helped someone that had put a schrader valve in place of their reservoir vent and would charge it with 5 psi like you mention... I'll just say they ended up with a leaky pump

 

[vetteboy79]

The pump will end up sending out more oil and bypass less. This can lead to too much flow in a restrictive system downstream of the pump, building heat and over pressurizing a system designed for a lower flow rate. The excessive flow can also make the steering more reactive at higher engine speeds and higher vehicle speeds creating a more twitchy steering wheel feel. Some pumps are not ported to full flow they need to bypass to keep oil in the pump or they will cavitate as they can not get the extra flow in and out.

This was my experience when I was screwing around with drilling that fitting. A little bit made it better, a little bit more and you can definitely tell it took a nose dive for the worse. Cavitating constantly, and although it was definitely fast, it was too much assist.

If I remember right, 3/16" was the point where it crapped out and I was glad I had an extra fitting to swap back. That was in a regular TC-style pump and I think 5/32 is where I ended up.

 

[DesertCJ]

Junkyard brass radiator, cut the cap area off and braze it on to your reservoir and run a low pressure radiator cap instead of whatever cap you were running before.

I run a PSC reservoir....none of that is going to work. Screwing a Schrader valve into the cap is easy?

 

[DesertCJ]

Not recommended. As fluid heats up, it will expand and potentially overpressure that pump shaft seal since the schrader won't do anything to limit pressure like a radiator cap will. The radiator cap vents just enough air as the fluid heats up and expands to limit pressure. I put a schrader valve on my monster truck reservoirs so that they can pre-charge before a show since they will typically be starting cold but this is separate from the cap which will still limit the pressure.

I just recently helped someone that had put a schrader valve in place of their reservoir vent and would charge it with 5 psi like you mention... I'll just say they ended up with a leaky pump

Noted....

https://www.mcmaster.com/4772K2-4772K202/

 

[RadialDynamics]

Noted....

https://www.mcmaster.com/4772K2-4772K202/

So that valve will relieve pressure as fluid expands to limit your reservoir pressure to 10 PSI but when you shut your engine off and your fluid cools down, it contracts and could end up creating a vacuum in the reservoir which will cause additional cavitation next time you go to start up. Radiator caps have an anti-vacuum valve that let's atmospheric pressure push air back in as the fluid contracts so that you never end up below atmospheric pressure. For as cheap as they are, you can't beat the functionality that they offer. The easiest option for the PSC reservoir without having to modify too much is to use their "anti-splash" 6 PSI valve kit which performs the same functions.

 

[DesertCJ]

So that valve will relieve pressure as fluid expands to limit your reservoir pressure to 10 PSI but when you shut your engine off and your fluid cools down, it contracts and could end up creating a vacuum in the reservoir which will cause additional cavitation next time you go to start up. Radiator caps have an anti-vacuum valve that let's atmospheric pressure push air back in as the fluid contracts so that you never end up below atmospheric pressure. For as cheap as they are, you can't beat the functionality that they offer. The easiest option for the PSC reservoir without having to modify too much is to use their "anti-splash" 6 PSI valve kit which performs the same functions.

Cool, I'll check it out!

 

[Provience]

there are plenty of recreational guys who want stuff to work and dont mind paying for it. people have no problem throwing down for a full hydro system from howe, psc, etc. because its a system with components designed to work together.

the guys using off the shelf pump, surplus rams and orbitals mixing up parts and hoping for the best. 60% of the time it works, the other 40% is misery.

i had a front row seat to someone trying to do what ScottRS did with his dual pump setup, even with a lot of input from Scott. lots of money, waling and gnashing of teeth. for what he was doing dual pumps was not needed looking back. a howe full hydro system would have done everything he wanted and then some in a simple package.

i feel weirdly target by this post

 

[DesertCJ]

Found this...
https://www.mcmaster.com/48935K25/
A lot less than PSC's valve. Would have to drill and tap an additional hole in the reservoir cap is all. Also...not as good but if installed from the bottom side of the cap might keep vacume to a minimum(.3psi less than atmospheric)?
https://www.mcmaster.com/1093K11/

 

[Bebop]

Soooooo, the PSC remote valve is manufactured by a company called Hydac.
You can buy one direct from them for much cheaper ($18).

Here is the technical brochure :

https://livhaven.com/wp-content/uploads/2016/01/hbv.pdf

I drilled and tapped my cap to 1/2NPT to put one in.

Does the job just fine, but IMO 6 PSI isn't enough. I'd like a higher relief, but their 10 PSI model has a MOQ that I can't meet by myself. IBB group buy anyone ?

 

[welndmn]

if you check out the website and look at the prices ($845 for a 4" reservoir ) i dont think the OP is going to have much luck with recreational offroaders buying his product

The 4door Jeep crowd will drop 10k on shocks, this spot is just expensive now.

 

[Weasel]

i feel weirdly target by this post

same, buggy is getting good parts. I'll let someone else spend the time on dialing in the steering parts. Would like to see more options with rams though.

 

[Provience]

same, buggy is getting good parts. I'll let someone else spend the time on dialing in the steering parts. Would like to see more options with rams though.

it's a tough sell to convince me that a ram isn't a ram. once you price out the odds and ends, the price is pretty close to the same so you are just paying for the parts and labor of getting whatever ends on your shaft you want when you buy the fancy one from PSC/Howe.

 

[DesertCJ]

Random thought crossed my mind. A vacume will pull air out of solution, so is air coming out of the oil as bubbles in your reservoir really a bad thing? Wouldn't all or most of the air get pulled after some amount of time?

 

[PAE]

Working on this surplus item from when I worked in the fabrication business.
I borrowed this from my ex

employer.

 

[HYDRODYNAMIC]

Random thought crossed my mind. A vacume will pull air out of solution, so is air coming out of the oil as bubbles in your reservoir really a bad thing? Wouldn't all or most of the air get pulled after some amount of time?

Cavitation is isolated lowering of pressure with force which can make liquids boil forming vapor.
Absolute vacuum is 0 and anything above 0 is pressure whether it be atmospheric ( the air pressure we live in) or a pressurized container or a high pressure area caused in liquid by the force of liquid moving.
Cavitation does not need to reach absolute for a vacuum to create a space entirely void of matter. Cavitation only needs to bring the isolated area pressure to the boiling point of the liquid at the isolated liquid temperature and then the liquid will change to a vapor state.
Raise the pressure and the boiling point goes up = more force can be exerted before cavitation starts.
Lower the temp = more force can be exerted before cavitation starts

Boiling a pot of water is not cavitation as force is not being applied to the liquid. Boiling a pot of water is also not creating a vacuum.

If you ever want to make crystal clear ice cubes you should boil the water to release the dissolved air otherwise when you freeze the water you will end up with a clouded cube.
Oil can also hold dissolved air or air bubbles. Boiling the oil will help release dissolved air. An air bubble of a given size at a given pressure can be doubled in size by cutting the pressure in half. It can also be shrunk by increasing external pressure.

If a pump is cavitating and pulling air out of the oil maybe it is a good thing? No because the instant that the force is gone the air will collapse on the object that created the external force and impact it with a concentrated jet of liquid causing pitting and erosion, if the oil is dirty then it will throw those particle into the surface like a water jet cutter pushing abrasive media across the material cutting it away.

So to answer your question removing air is good but once it is gone it is gone. You can cavitate/boil liquid into a vapor and let it return to a liquid over and over again and never end up with a growing air pocket or bubble.

 

[ScottRS]

Random thought crossed my mind. A vacume will pull air out of solution, so is air coming out of the oil as bubbles in your reservoir really a bad thing? Wouldn't all or most of the air get pulled after some amount of time?

Yes, you just can't leave the vacuum on it in operation, or you'll cause cavitation. In use, you want pressure to help reduce cavitation. That's where the radiator cap comes in handy, it'll work as a pressure hold/relief and a vacuum breaker in one.

 

[HYDRODYNAMIC]

Working on this surplus item from when I worked in the fabrication business.
I borrowed this from my ex employer.

Super cool!
Round aviation reservoirs usually have a pickup tube going to the center of the sphere. Regardless of orientation the air will always be opposite of the side of gravity or centrifugal force and the pickup tube will be in the middle which is the furthest distance from the sides.
My first reservoir on the buggy used this concept in tube form to keep the air at the ends of the reservoir tubes when the buggy was on its side. That was back when I had full system flow going through the reservoir. While it worked great I learned that a reservoir of that size was not needed if the system could be supercharged or recirculated or whatever you want to call not sending full flow through the reservoir. That when the reservoir size dropped from 18 gallons to 1 gallon.

 

[HYDRODYNAMIC]

Yes, you just can't leave the vacuum on it in operation, or you'll cause cavitation. In use, you want pressure to help reduce cavitation. That's where the radiator cap comes in handy, it'll work as a pressure hold/relief and a vacuum breaker in one.

This just made me think about hooking up an engine vacuum line to the reservoir to help increase the size of the bubbles when purging a system of air at startup at low idle. Same could be used for remote radiator circuit purging. Just need to make sure whatever you are connected to doesn't fill up with liquid and start to get pulled into the intake. Yes a vacuum pump is better but you always have the engine vacuum with you on the trails.

 

[DesertCJ]

Yes, you just can't leave the vacuum on it in operation, or you'll cause cavitation. In use, you want pressure to help reduce cavitation. That's where the radiator cap comes in handy, it'll work as a pressure hold/relief and a vacuum breaker in one.

How is the pump going to cavitate if all air has been removed from solution in the oil? I'm not really suggesting running the system under a constant vacuum though. If there's a 10psi pressure relief and the oil heats up with use/expands, it could possibly pressurize the air in the top of the reservoir up to 10psi in this case. Without a vacume break/relief, it's possible that a vacuum will occur when the oil cools and the vehicle is sitting. Is the air in solution not being pulled from the oil the entire time the vehicle is sitting and gathering at the top of the reservoir? How is that a bad thing? I don't think it would take very long for the oil to heat up/expand enough after starting the engine to relieve whatever vacuum existed while at rest(IE reach 0psi or 14.5/atmospheric).In fact, it's not even a given that a vacuum would ever form if the pressure never exceeded 10psi.

 

[DesertCJ]

Cavitation is isolated lowering of pressure with force which can make liquids boil forming vapor.
Absolute vacuum is 0 and anything above 0 is pressure whether it be atmospheric ( the air pressure we live in) or a pressurized container or a high pressure area caused in liquid by the force of liquid moving.
Cavitation does not need to reach absolute for a vacuum to create a space entirely void of matter. Cavitation only needs to bring the isolated area pressure to the boiling point of the liquid at the isolated liquid temperature and then the liquid will change to a vapor state.
Raise the pressure and the boiling point goes up = more force can be exerted before cavitation starts.
Lower the temp = more force can be exerted before cavitation starts

Boiling a pot of water is not cavitation as force is not being applied to the liquid. Boiling a pot of water is also not creating a vacuum.

If you ever want to make crystal clear ice cubes you should boil the water to release the dissolved air otherwise when you freeze the water you will end up with a clouded cube.
Oil can also hold dissolved air or air bubbles. Boiling the oil will help release dissolved air. An air bubble of a given size at a given pressure can be doubled in size by cutting the pressure in half. It can also be shrunk by increasing external pressure.

If a pump is cavitating and pulling air out of the oil maybe it is a good thing? No because the instant that the force is gone the air will collapse on the object that created the external force and impact it with a concentrated jet of liquid causing pitting and erosion, if the oil is dirty then it will throw those particle into the surface like a water jet cutter pushing abrasive media across the material cutting it away.

So to answer your question removing air is good but once it is gone it is gone. You can cavitate/boil liquid into a vapor and let it return to a liquid over and over again and never end up with a growing air pocket or bubble.

I'm not suggesting running the system under a constant vacuum. Or that I want the pump to cavitate. Obviously we want the opposite. I may not be the brightest but I'm not seeing how this vacuum at rest changing to pressurized wouldn't be the best of both worlds?