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Steering Coolers: Radial Dynamics vs Howe

I keep a gauge on my low side ahead of the filter .. It stays around 20 psi
 
I have a pile of Setrab coolers of varied series. Almost all are rated ~250psi, a couple say 170psi "working pressure". I do believe they make some specific coolers rated to 300psi "working pressure".
The 250psi rated coolers do say they have a 350psi burst pressure.

None list a flow rate, only pressure drop through the cooler, which all are ~1-2 psi.

With full hydro, what kind of max pressure is generally on the side returning to the reservoir? I understand the pressure side varies greatly due to what you're doing at the time. I'm assuming the return side is somewhat the same?
Coolers are on the return side going back to the reservoir. The reservoir shouldn’t see more than maybe 10PSI. The cooler shouldn’t have more than maybe 5PSI drop. Depending on where the filter is you shouldn’t add more than another 10PSI. So the cooler shouldn’t see anything over 25PSI. I’d pick the cooler with the biggest ports and biggest surface area.
 
Coolers are on the return side going back to the reservoir. The reservoir shouldn’t see more than maybe 10PSI. The cooler shouldn’t have more than maybe 5PSI drop. Depending on where the filter is you shouldn’t add more than another 10PSI. So the cooler shouldn’t see anything over 25PSI. I’d pick the cooler with the biggest ports and biggest surface area.

Don't know about other brands but, just about every single Setrab cooler has 22mm o-ring boss ports on them and you can get M22 to AN adapters from -4AN to -16AN.

I have the bigger Howe cooler for my full hydro/10"ram/TC pump. Good to know if I ever have hot oil issues, I can just slap one off the pile into the mix.

If anyone thinks Setrab coolers cost too much. Get on Ebay, find the guys selling NASCAR take offs, because they are timed out and sold dirt cheap.:smokin:
 
I'll be the first to say that of the log style coolers like the one I make, none of them will be as efficient at heat transfer as something like a Setrab or CBR cooler. However, each vehicle needs to consider the tradeoffs of all the different options. The benefit of my cooler is robustness and reliability at the tradeoff of efficiency. Ultimately, the question is how much cooling does a car really need and in most, although not all cases, my cooler provides enough cooling to maintain temps in high demand applications. I also have several 4400 teams running two of my coolers which is enough to keep some of the largest displacement RDT or TT pumps within reasonable operating temp during KOH. The benefit is that you can throw rocks at them or drive through thick brush without worrying about poking a hole in a cooler tube.

I just had a call with a trophy truck team the other day that won't go back to a "real" cooler again because they had one crack and leak which took them out of contention for podium during a major desert race just before the finish line. If you have the packaging availability and want to run a fin and tube cooler with a fan, I have no problems with that whatsoever.

Where packaging and potential damage are a concern, the log style coolers do have some benefits and of the log style ones, there are some fundamental differences between the one I make and a Howe or PSC cooler, as noted previously. Everything is about finding balance and what best fits your needs.
 
I'll be the first to say that of the log style coolers like the one I make, none of them will be as efficient at heat transfer as something like a Setrab or CBR cooler. However, each vehicle needs to consider the tradeoffs of all the different options. The benefit of my cooler is robustness and reliability at the tradeoff of efficiency. Ultimately, the question is how much cooling does a car really need and in most, although not all cases, my cooler provides enough cooling to maintain temps in high demand applications. I also have several 4400 teams running two of my coolers which is enough to keep some of the largest displacement RDT or TT pumps within reasonable operating temp during KOH. The benefit is that you can throw rocks at them or drive through thick brush without worrying about poking a hole in a cooler tube.

I just had a call with a trophy truck team the other day that won't go back to a "real" cooler again because they had one crack and leak which took them out of contention for podium during a major desert race just before the finish line. If you have the packaging availability and want to run a fin and tube cooler with a fan, I have no problems with that whatsoever.

Where packaging and potential damage are a concern, the log style coolers do have some benefits and of the log style ones, there are some fundamental differences between the one I make and a Howe or PSC cooler, as noted previously. Everything is about finding balance and what best fits your needs.
Great info. Thanks!
One of the reasons I was considering the log style was packaging. The current steering cooler I use is a fin/tube style that is directly up against the front of my radiator. I would really love to not have that in front of the radiator to ensure I'm getting max air pulling through the radiator.

anyone know how the efficiency of the radiator decreases when it has another cooler on the front of it. The one I am using does not cover the entire radiator, maybe 1/4 of it.
 
Bad luck to talk about steering I guess ! Been flawless for a year of wheeling since finishing my build! Some how managed to crack the case on my psc cbr pump over the weekend .. Big mess
 

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Bad luck to talk about steering I guess ! Been flawless for a year of wheeling since finishing my build! Some how managed to crack the case on my psc cbr pump over the weekend .. Big mess
Glad to hear that a mess is all it made. I'm curious if you took a hard impact or hit full lock when it fractured?

CBR's are one of the few pump types that I have seen split in this manner before. The others are P pumps and TT pumps, all of which share the same internal architecture in which high pressure oil is pushed into the rear half of the pump body where the housing is the weakest.

The CB, TC, and RDT pumps are all fundamentally opposite, high pressure oil is pushed into the forward part of the pump housing where the front closure of the housing holds everything together far stronger and to date, I have never seen one of these pump housings split like that.
 
Nothing to out of the ordinary when it let go... Im fairly hard on it regularly but its seen much worse impact wise .. Emailed back and forth with PSC to see if i could buy an empty case.. No luck .. They also told me the reason it split is because im running front and rear steer off a single pump and I need 2 pumps to make it work.. I didnt respond further.. For now to get me rolling im swapping on a rebuilt TG pump with the steel housing and in the future when I save up some pennies ill be ordering a pump from you
 
Glad to hear that a mess is all it made. I'm curious if you took a hard impact or hit full lock when it fractured?

CBR's are one of the few pump types that I have seen split in this manner before. The others are P pumps and TT pumps, all of which share the same internal architecture in which high pressure oil is pushed into the rear half of the pump body where the housing is the weakest.

The CB, TC, and RDT pumps are all fundamentally opposite, high pressure oil is pushed into the forward part of the pump housing where the front closure of the housing holds everything together far stronger and to date, I have never seen one of these pump housings split like that.
So is it safe to assume that's why you don't offer CBR and instead have TC pumps on your site?
 
So is it safe to assume that's why you don't offer CBR and instead have TC pumps on your site?
One of a few reasons. Number one is when I did sell CBR's back before I brought all of my pumps in house, I dealt with too many call backs about noise and performance issues with them compared to other pumps so I simply stopped selling them. At the time I was also selling my CB-X (modified CB) pumps which were made for me by another aftermarket steering company and while they had the stronger design related to the internal architecture noted above, they had another design feature in common with the CBR pumps and that is having a c-clip shaft.

The CB, CBR, and P pumps (among others) all have a c-clip on the tail end of the shaft which is the only thing preventing the shaft from being able to pull straight out of the front of the pump body. As such, they have no thrust load support so if the mounting bracket gets bent or the pulley is misaligned from the belt, that load gets transferred to the pump rotor internally. The rotor is spinning with the shaft and is it surrounded by stationary bits so any belt misalignment results in very rapid pump wear.

TC, RDT, and TT pumps all have ball bearings on the shaft that support some amount of axial thrust and in doing so, there is no need for a c-clip on the tail end of the shaft so the rotor is therefore fully floating. The CB-X pumps were good pumps but pulley alignment was their only Achille's heal. When I brought all of my pumps in house about a year ago, I was able to make my TC's outperform the CB-X with improved reliability so I focused on those and discontinued the CB-X.

So between the internal architecture/housing strength considerations, shaft thrust load capacity, and fully floating rotors, that is how I have ended up with only TC and RDT pumps available in my product lineup.
 
One of a few reasons. Number one is when I did sell CBR's back before I brought all of my pumps in house, I dealt with too many call backs about noise and performance issues with them compared to other pumps so I simply stopped selling them. At the time I was also selling my CB-X (modified CB) pumps which were made for me by another aftermarket steering company and while they had the stronger design related to the internal architecture noted above, they had another design feature in common with the CBR pumps and that is having a c-clip shaft.

The CB, CBR, and P pumps (among others) all have a c-clip on the tail end of the shaft which is the only thing preventing the shaft from being able to pull straight out of the front of the pump body. As such, they have no thrust load support so if the mounting bracket gets bent or the pulley is misaligned from the belt, that load gets transferred to the pump rotor internally. The rotor is spinning with the shaft and is it surrounded by stationary bits so any belt misalignment results in very rapid pump wear.

TC, RDT, and TT pumps all have ball bearings on the shaft that support some amount of axial thrust and in doing so, there is no need for a c-clip on the tail end of the shaft so the rotor is therefore fully floating. The CB-X pumps were good pumps but pulley alignment was their only Achille's heal. When I brought all of my pumps in house about a year ago, I was able to make my TC's outperform the CB-X with improved reliability so I focused on those and discontinued the CB-X.

So between the internal architecture/housing strength considerations, shaft thrust load capacity, and fully floating rotors, that is how I have ended up with only TC and RDT pumps available in my product lineup.
Sounds like I need to get in touch about ordering a TC pump to replace the CBR I bought from PSC. Thanks for the insight. :)
 
I realise we are side tracking this cooler thread a bit here but hey atleast its steering related!

I just rebuilt this trail-gear steel housing pump and while doing so I did a bunch of measuring .. It seems extremely similar to the aluminum PSC pump ... Rear cap measures the same.. Pump rotor measures the same.. The rotor housing has a .075" larger od but seems it would fit the TG housing.. The PSC has a m20 orb thread on the suction side vs m18 for the TG.. Also the TG has a .75" shaft with a .66 pulley vs the PSC shaft is .66 through to the rotor splines.. I do like the idea of the proper bearing supported shaft in your Radial dynamic pumps ... The TG pump I picked up and rebuild had excessive thrust wear
 
I realise we are side tracking this cooler thread a bit here but hey atleast its steering related!

I just rebuilt this trail-gear steel housing pump and while doing so I did a bunch of measuring .. It seems extremely similar to the aluminum PSC pump ... Rear cap measures the same.. Pump rotor measures the same.. The rotor housing has a .075" larger od but seems it would fit the TG housing.. The PSC has a m20 orb thread on the suction side vs m18 for the TG.. Also the TG has a .75" shaft with a .66 pulley vs the PSC shaft is .66 through to the rotor splines.. I do like the idea of the proper bearing supported shaft in your Radial dynamic pumps ... The TG pump I picked up and rebuild had excessive thrust wear
The TG pump is a Saginaw CB type which is a .75" shaft diameter and would normally share pulleys with P pumps which are also .75" shafts. TG necked them down in front of the shaft seal to 0.664" to match the TC and CBR pumps in order to share pulleys. The CB-X pumps that I sold for a while were similar, they had a 0.75" shaft necked down to 0.664". The CB and CBR cam rings and port plates are very similar dimensions but are not interchangeable as they are fundamentally very different pumps despite looking so similar externally.
 
Ok good to know.. I was thinking of swapping the psc guts into the TG pump for a science experiment to learn the hard way .. Would you happen to know if a stock cbr case off a newer chevy would fit the psc stuff? Be nice to have another spare on the shelf ... Ultimately I have my eyes on your pro series TC ... What sort of rpm would that pump be ok with?
 
Any stock pump will have a smooth bore inlet port for use with a plastic reservoir that seals via an o-ring. Only the aftermarket pumps will have a threaded inlet port in the casting. The internals should be interchangeable though. *Edit: I will note that most Saginaw pumps were made with multiple displacement options and with a reman or parts store replacement pump, it's a crap shoot what displacement cam ring and cam ring material you will get.

As for my Pro Series TC pumps, I have no problems running them up to 7500 or 8K RPM. I have a few customers that run them higher for brief periods because there are some engines and applications where we just don't have much choice but the lower you can keep the peak RPM, the longer the pump will last.
 
This has been very helpful, informative!! .. Really like that Radial Dynamics makes himself available and provides tech directly, open and honest tech.

I have a bit of a follow-up question: After talking to the folks at HOWE during this years KOH, one of the "best practices" that came up was adding CAPACITY to your steering system among a few other things.

  • the "reservoirs" dont actually add capacity to the system, the only thing they do is allow for contraction and expansion for heat etc.
  • the longer the lines the better, and only run the high pressure stuff where it says you need to, the reason being, low pressure has thinner walls and therefore holds more fluid. Anything you can do to add capacity to the system is worth doing.

So assuming the above as correct, and looking towards both effective cooling AND adding capacity, I wondered about routing my steering lines back to my rear mounted radiator that has an incorporated heat exchanger. Not only would I pick-up 12' of extra hose (and capacity) but in using a heat exchanger set-up I'd keep things fairly simple and avoid introducing a fan, relay, electrical circuit etc. Keeping is simple just like a log style cooler.

Suppose the main question is, what sort of steering temps are we seeing? Would using a heat exchanger provide for added cooling OR would I end up ADDING more heat to my steering fluid with this approach?

With a stand alone trans cooler already set-up, I am wondering how best to make use of my CBR radiator exchanger ... steering has become my next "priority"
 
  • the "reservoirs" dont actually add capacity to the system, the only thing they do is allow for contraction and expansion for heat etc.
Not sure I'm following the above. Don't heavy equipment hydraulic systems run accumulator tanks or giant (for our uses) reservoirs that add a ton of capacity in terms of fluid and therefore heat load capacity?
 
  • the "reservoirs" dont actually add capacity to the system, the only thing they do is allow for contraction and expansion for heat etc.
Howe resis don't.
That's why you use a RD resi

  • the longer the lines the better, and only run the high pressure stuff where it says you need to, the reason being, low pressure has thinner walls and therefore holds more fluid. Anything you can do to add capacity to the system is worth doing.
Complete BS.
 
Not sure I'm following the above. Don't heavy equipment hydraulic systems run accumulator tanks or giant (for our uses) reservoirs that add a ton of capacity in terms of fluid and therefore heat load capacity?
If HOWE was talking, I am pretty sure he means the main players, HOWE and PSC don't really add capacity.
The Radial dynamics is quite a bit larger than those.
 
If HOWE was talking, I am pretty sure he means the main players, HOWE and PSC don't really add capacity.
The Radial dynamics is quite a bit larger than those.
It's a design problem from Howe and PSC, not a sizing deal.
 
Capacity helps these systems out, absolutely. Reservoirs not adding capacity, if that's what Howe said, that would be because of their reservoir design. Their reservoirs with the spin on filters integrated on the bottom don't really circulate the oil in the upper tank portion. There is a little bit of turbulence and mixing at the bottom but the oil in the tank is more or less stagnant so no, you aren't really adding much effective capacity. This was actually the entire reason I started my business after developing the reservoir to redesign something that circulated 100% of the fluid in the tank.

Regarding hose size, you don't need high pressure hose on the return or the feed but it doesn't really hurt to use high pressure hose there. Regarding wall thickness and actual ID, every manufacturer is going to be a little different and you have to look at their actual specs. I don't care so much about hose dash size, per se. I care about actual hose ID based on a flow rate to match up oil velocity through said hose. If using a manufacturer that tends to run undersize, then use the next size larger, simple as that.

Just for reference:
 
I forgot to add, regarding running your steering to an integrated heat exchanger in your radiator, I don't generally recommend using engine coolant as the cooling medium since it will typically be hotter than most steering systems run in the first place. However, normal steering temps depend somewhat on your application. I'd say that most of my recreational customers run 180F or below. Racing applications can easily see fluid temps up to the low 200's but I do have some extreme use cases and have seen plenty of desert racing teams run upwards of 250-270F successfully.

With a radiator running around 200+F already, it doesn't do much to cool a steering system unless it is a very extreme use case.
 
Howe resis don't.
That's why you use a RD resi

Not so fast there Bebop:flipoff2:. The biggest Howe reservoir is 6"x15". The biggest RD monster truck reservoir is 5"x17". That's damn close to being the same thing. Not knocking either company, but for each reservoir from one, you can find a matching reservoir from the other, capacity wise.

If someone want a shit ton of capacity.......use a drysump tank, they're also made to remove air bubbles from oil. I've got a drysump tank that holds 6 gallons.:flipoff2:



RadialDynamics

What are your thoughts on making the return lines to and from the cooler as long as possible? Does it not add some extra capacity and possibly do (if even a tiny bit) a little extra cooling of the fluid.

Are there drawbacks to doing this?
 
Not so fast there Bebop:flipoff2:. The biggest Howe reservoir is 6"x15". The biggest RD monster truck reservoir is 5"x17". That's damn close to being the same thing. Not knocking either company, but for each reservoir from one, you can find a matching reservoir from the other, capacity wise.
Howe's resi design and RD are very different.
Only one of them uses all the fluid that's in it. The other one holds fluid for heat expansion purposes only.

If someone want a shit ton of capacity.......use a drysump tank, they're also made to remove air bubbles from oil. I've got a drysump tank that holds 6 gallons.:flipoff2:
I was thinking about it, but at the end of the day, if you want something that fits well, you end up buy a RD resi, because that's exactly the same thing but made for a PS system.

RadialDynamics

What are your thoughts on making the return lines to and from the cooler as long as possible? Does it not add some extra capacity and possibly do (if even a tiny bit) a little extra cooling of the fluid.

Are there drawbacks to doing this?

It doesn't matter.

Copied from another post I made on another forum which was talking about how Jeff Howe said that moving the resi away from the pump was good because it would add volume because of the extra length of line :

Provided you're using a AN12 line for feed, 2ft of hose distance is 10.6in3 (area of a 0.75" circle is 0.441786 in2), which is equivalent of adding less than 1" of volume in a classic 4" TT resi (area of a 4" circle is 12.5664 in2). And that's if you compare it to a resit that would be directly attached to the pump.

At 9GPM, which is the standard TT pump flow, if you have a 4 qt fluid capacity in your system (which is already pretty good), and assuming the totality of the fluid gets circulated (which it isn't with the stagnant fluid in the Howe resi and ram extremities), it would take 6.7 seconds to circulate the whole fluid volume once. If you add 10.6in3 of volume this number goes to 6.9 seconds.

IE the extra fluid volume argument is BS. It has more to deal with fluid dynamics than anything.
 
What are your thoughts on making the return lines to and from the cooler as long as possible? Does it not add some extra capacity and possibly do (if even a tiny bit) a little extra cooling of the fluid.
Ford did that on the pickups for 15yr and is probably still doing it on the vans. :laughing:

That was more for crude cooling though, not volume.
 
I don't have a problem with someone running a rear cooler for their steering and running their return line all the way to the back of the car for that purpose but I would say that if your only reason for doing it is to get extra capacity then it's not necessary. Some people run a rear cooler for packaging because they have no room up front. Either way, it's all about sizing the hose to get the proper flow velocity (for return lines, around 10 FPS) which balances pressure loss due to friction (maximum velocity) and being able to push any air pockets or solids contamination back to the reservoir or filter (minimum velocity).

Remember that while extra capacity helps, it is only one piece of the equation. It is better to have a properly sized and balanced system than one that is improperly sized with higher total capacity. Even with a system having a larger total volume of oil, in an endurance race with long run times, you will ultimately hit a steady state at which your heat load and cooling capacity determine the fluid temp regardless of total volume.

With the vortex design in particular, there is a relationship between the pump flow rate and reservoir diameter in terms of de-aeration effectiveness. Using my monster truck reservoir in a rock crawler, while it would add a ton of capacity, is simply not necessary because the smallest 3.5" size works great with pumps up to 6 GPM max regulated flow rate and we can successfully get away with relatively small total oil capacity versus what hydraulic industry guidelines suggest should be attempted.
 
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