First of all, hello!
I just signed up to this site officially, but I’ve been lurking for the past few months. I recently acquired a 1994 q45a for super cheap. Black on black with 112k miles. Bought her back in November and left her at my job site up until I got laid off due to our best friend covid-19 . Got laid off March 23, went to pick her up the very next day and drove her home. So with all this free time I’ve had at home I tore the intake manifold off replaced all the hoses under there along with both new knock sensors and all 8 injectors. New gaskets etc etc. now when I bought the car the previous owner told me about the two blown struts out back. So I had no intention of keeping the active suspension functional so I tore it all out these past few days. Now I’m stuck at the very last part, I decided to loop the system but after searching and searching I couldn’t find any pictures of how you guys are doing it. If you can point me in the right direction that would be awesome that’s the last thing thats keeping me from starting my car for the first time since I tore into it. Thank you in advcance!

The best way to complete an active to standard conversion is to replace the harmonic balancer (pulley), water pump pulley, replace with standard Q45 base power steering pump and the associated pump to block bracketry.
Another potential option, though not verified, is to replace pump and brackets, and kludge your 7 groove active pump pulley onto the standard pump (in place of the 4 groove pulley). Probably invlolves custom welding.
These are the only ways I would recommend.
I know its been done to "loopback" the active pump output onto itself. Again, I strongly advise against this method unless you are willing to spend the time and money to fabricate REAL (not cut up and thrown together) intake/outlet system for the active side of the pump. using the existing reservoir, so you can keep pumping at least a liter and preferably two thru the pump strictly for purposes of keeping the tandem pump properly lubricated.
Or, say "F" it and destroy your irreplaceable existing pump by not properly lubricating it. It'll probably last a hundred miles or so with no hydraulic fluid.
The unfortunate reality is that in the tandem pump design the shaft goes thru the active half first before it drives the power steering vanes.
I may be interested in your multivalve donor if (and only if) the system has NOT been contaminated (you cleaned all dirt away carefully from fittings before removing the hydraulic lines.
You have a very unique and complicated car (although less so as a non-active). Treat it with love and enjoy a piece of Japanese engineering that was ahead of its time!

to Nico!

3Q Jay wrote: ↑

Sat Apr 18, 2020 7:57 am

The best way to complete an active to standard conversion is to replace the harmonic balancer (pulley), water pump pulley, replace with standard Q45 base power steering pump and the associated pump to block bracketry.
Another potential option, though not verified, is to replace pump and brackets, and kludge your 7 groove active pump pulley onto the standard pump (in place of the 4 groove pulley). Probably invlolves custom welding.
These are the only ways I would recommend.
I know its been done to "loopback" the active pump output onto itself. Again, I strongly advise against this method unless you are willing to spend the time and money to fabricate REAL (not cut up and thrown together) intake/outlet system for the active side of the pump. using the existing reservoir, so you can keep pumping at least a liter and preferably two thru the pump strictly for purposes of keeping the tandem pump properly lubricated.
Or, say "F" it and destroy your irreplaceable existing pump by not properly lubricating it. It'll probably last a hundred miles or so with no hydraulic fluid.
The unfortunate reality is that in the tandem pump design the shaft goes thru the active half first before it drives the power steering vanes.
I may be interested in your multivalve donor if (and only if) the system has NOT been contaminated (you cleaned all dirt away carefully from fittings before removing the hydraulic lines.
You have a very unique and complicated car (although less so as a non-active). Treat it with love and enjoy a piece of Japanese engineering that was ahead of its time!

Hello! Thank you for the quick reply! I did think about swapping out all of the active components (pulleys, pump...) for the non active stuff and just make my life a little easier, but with the quarantine and closures it’s hard to access junk yards around me. I can order a reman non active pump from autozone for a decent price as I have friends that work there so that’s an option! I would like to loop it for now even if it means to spend a little time and money fabbing some parts without hacking them. I just don’t know much about the system I know there’s a input and output side, what I don’t know is what psi the system runs at and if I were to use the stock active reservoir how would I bring down the psi on the output side before it reaches the reservoir. I can have hoses made to accommodate the loop system there are plenty of places that make them around me ( lots of agriculture here) by no means do I want to hack this car up, I know taking the active out is already a hackjob in some of your eyes but going as low as possible is my goal with this car as I love vip cars and this is an actual vip platform car. This car was ahead of its time that’s without a doubt! I love it and I have only driven it around 80 miles oh and you are welcome to have any of the active stuff I did clean everything off with a pressure washer before I started working on it.

Q451990 wrote: ↑

Sat Apr 18, 2020 9:37 am

to Nico!

Thank you!!!

I would be interested in any left over active parts as well. I sent a personal message.

Thanks-PM me and we can discuss what might be good to harvest.
I don't fault you for converting from Active.....as long as you do it right!
To be sure, actives are not for the faint of heart. And there is no ongoing support for them (Nissan doesn't even make the hydraulic fluid anymore--although I have started cutting in CHF-11s as a substitute).
Remember if you do go with the base (2-wheel steering) PS pump you will still need a pulley and brackets (even if you are planning to re-use your 7-groove with welding I think (not sure) that the pump shaft diameter and keyway are different).
If you can have a high pressure hose fabbed, I think you are on the right path.
The active pump suction hose is a long one with both metal and rubber and connects directly to the active reservoir, so leave that one as long as not leaking.
The active pump discharge goes via hose first to an accumulator that is just forward of the A/C clutch. you'll want to fab a re-design hose that goes from the pump outlet back to the reservoir. the reservoir return in the original design is a two part hose, with the main part coming from the active radiator. You can disconnect the lower hose from the active radiator and make that your connection from the pump output back to the reservoir (thru the active oil cooler). You mentioned pump output pressure-the max pump output is 1400-1500 psi, but it doesn't usually run at that level. I'd suggest orificing your newly fabbed hose so that you've got about a 0.050" opening to lower the pressure going back to the reservoir. That's just back of the envelope--YOU are going to be the engineer redesigning this if you go that route.
one other thing: that two part hose that goes between the oil cooler and the reservoir: I believe you will have to plug the smaller hose where it plugs into a small canister filter (identified with 3 hex screws in a triangle at the bottom of the filter)that is attached to the multivalve.
Of course, if you intend to re-purpose your active oil cooler as a tranny cooler or other (which is not a bad idea), then you'll need to fab a return to the reservoir that doesn't go thru the cooler.
One other important thing regarding loopback:
regardless of how you complete a closed fluid circuit for the pump, when you connect everything back up, you will need to suction the inlet line to the active pump, as air will trap and the pump will cavitate and eventually seize, rendering all your loopback effort for naught.
The way the factory designed this was to hook an a/c vac pump to the filler neck on the active reservoir. That does indeed work, and is important.....
AND....
bear in mind that at 26 years old, it is very likely that your active pump (in particular the solenoids on the bottom of the pump and perhaps the forward seal on the pump) is leaking. Both of mine were. I have resealed the pumps on both cars (and re-ringed the power steering side in the process). I mention this as another reason why if you do loopback, keeping the reservoir so you can check and maintain a quantity of fluid in the system is important.

Just a friendly note, new member with less that 10 posts cannot send or receive PM's (except to staff).

ah, thanks rogue one....forgot about that.
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