Powersteering options?

[giryan]

So, I've got a powersteering leak, mildly severe in that most times the PS just isn't working because it's lost all the fluid.
And so I'm looking at options.

I could just get some new hoses made up, but from the look of it I just have the stock GM pump feeding into the Rx7 rack, which from what I was reading on No Rotors is possibly why the leak, because the pressure from the pump is too much?

LS Swap Power Steering - The Everything Thread

LS Swap Power Steering - The Everything Thread

www.norotors.com

I'm mildly tempted to see about getting the Turn One pump. My fabrication skills definitely aren't up to much, and it seems like a good option, which should be nearly bolt in place and buy some hoses.

 

[Spendyrx]

I got a Mercedes 12v electric pump!

 

[Gunnytron]

I've not heard of the GM ones leaking before. There is a post somewhere on norotors about using the stock rx7 pump. I can't remember how involved it was.

I am using the GM pump with a restrictor from turn one.

 

[4packet]

Doesn't sound like you've located where the leak is yet? Not sure why the GM hoses would leak with the pump they were designed to run with though, or am I missing something? The reason to reduce the pressure (*actually its flow not pressure) out of the pump is to reduce the assistance to the rack.

I'm running the LS3 Camaro pump with the Turn One flow restrictor and I also shimmed the pressure relief spring internally. The former reduces the rack assistance and the latter reduces the pressure spike to the rack when you hit the lock stops. I've used the standard Mazda metal pipe that runs along the rack to the LHS and had a screw on fitting welded on. Then it was simply a case of making a high pressure hose up with simple push fit connections to the hose. Over 30k miles and still good. More details on norotors. Search 'RHD LS3 99' or something similar.

You don't want to be running the PS pump dry, it relies on the PS fluid for lubrication and the contact forces are going to be pretty high considering the pressure it runs. If it has started to break up, then you may have damaged the rack, or at least filled it and all the lines with contamination.

*edit - rack assistance is as a result of pump flow capability, not pressure, hence why the flow restrictor works.

 

[giryan]

Thanks for all the replies.

heh, yes, I didn't mention that the leak's from a coupling in the hose did I? doh.
I'm not quite sure why it's set up like this, but there's a hose from the pump, into a coupler to another hose, to the Mazda cooler(?)/looped hardlines, and then into the rack.
It's the link between the two hoses that's leaking.

Yeah, I've been topping it up regularly, but definitely hoping nothing too bad has happened internally

Sounds like just fixing the hose situation is the best bet for now

 

[4packet]

That's the low pressure return line. No stress fixing that. I've used a new Setrab cooler on my circuit (track work and restrictor heat the fluid a lot), so not sure what diameter the stock Mazda looped cooler is vs the GM pump. It might be that the coupler you mention is a reducer as the hoses are different ID. I'd just inspect/fix/replace hose and call it done. It's going to be a pretty obvious leak as there's hardly any pressure there.

 

[giryan]

Ohhhh, that sounds like even better news, I'll definitely have to double check the plumbing though, as a friend who looked reckoned it was on the out side of the pump, not the return.

 

[4packet]

High pressure line is connected to the pump, return line is connected to the plastic reservoir. If the coupling you describe is in fact on the high pressure line then it could be an external flow restrictor.

 

[giryan]

Excitingly I went and looked at the PS, and the leak is on the low pressure side.
(in some vague defense of my friend's assessment, both hoses disappear between the starter motor and the front subframe)
So, I just need to find a hose that's about 10mm ID on one end, and about 15mm? on the other