overdriving my power steering pump
- Thread starter chevymog
- Start date
Most pumps have an internal bypass so when the pressure gets to high it opens up chances are you are already getting to that point with a stock pump if you need more performance out of your pump I would buy an aftermarket one or you will probably have premature failure
flexyfool
GDW
- Location
- Boise, Idaho
6" OD is standard. A hydro-assist kit, I bought 13 years ago for a Bronco from Duff, came with a custom machined smaller pulley. That smaller pulley with a high flow PSC pump now powers the full hydro steering and brakes on my buggy. The combo provides full response at idle, for both steering and brakes, where a 6" pulley will not. The belt will slip when the steering binds hard, but maybe this is a good thing. You might see if Duff will sell the pulley separate.
flexyfool
GDW
- Location
- Boise, Idaho
The pulley has been in continual use driving various pumps for all those years with no premature failures.
flexyfool
GDW
- Location
- Boise, Idaho
A post over on Pirate says a pulley from an old Jeep Cherokee is smaller than 6".
flexyfool
GDW
- Location
- Boise, Idaho
Or you could ream out the hole on an alternator overdrive pulley like this one http://www.summitracing.com/parts/sum-g3969/overview/ . You will have to mess around with the brackets since alternator pulleys have no offset and pump pulley have offset.
AaronPaige
Well-Known Member
- Location
- Price ut
I'm interested in this too I have a similar problem on my psc pump, I'm pushing twin 3 in rams and they don't offer a bigger pump. I found a smaller serpentine pulley but don't have room for the width any other ideas for a smaller o.d. Pulley for a p style pump
- Location
- The Land Northward (Bountiful), Utah
Aaron. I'd run twin pumps.
flexyfool
GDW
- Location
- Boise, Idaho
Or maybe some kind of ag or earth mover pump.
A smaller pulley only lowers the RPMs at which the pump puts out full flow and pressure. Going to a 5" from a 6" lowers the RPMs by 17%. I'm pretty sure a typical pump is working at full capacity in the low teens engine RPM. For example, if the pump is at full capacity at 1200 RPM then a 5" pulley takes that down to 996 RPM. Is this what you are needing?
Last edited:
that is what i am looking for when i am just cruising around in a higher gear at low rpms i have terrible steering almost like i have no power steering at all. Or when crawling and not giving it alot of throttle.
maybe i will go to the part store and have them pull a few different pullys off the shelf.
maybe i will go to the part store and have them pull a few different pullys off the shelf.
AaronPaige
Well-Known Member
- Location
- Price ut
I had no luck with anything on the shelf or in there books at the parts stores, just lower rpm would help in my situation, I'm getting all the pressure out of the pump that I need it's the gpm that is killing me, if I could find a simple and light 12 volt systems I think it would be sweet, but every time I look in to it all I find is boat systems and they can't constantly produce enuf
AaronPaige
Well-Known Member
- Location
- Price ut
I couldn't get Howe to tell me just how far they could take a pump but psc built my whole system and "custom tuned" the pump, they work great for a while but eventually bypas and blow the back/tank off, in order to get what I wanted I know the reliability goes down but, any better ideas...
flexyfool
GDW
- Location
- Boise, Idaho
There are a lot of options here: http://www.northerntool.com/shop/tools/category_hydraulics+hydraulic-pumps_0_0_P-Price|1?
The ones with an electric clutch (like an AC pump) are interesting.
The ones with an electric clutch (like an AC pump) are interesting.
The factory setup wouldn't be bypassing at low rpms though, where you'd want more pressure for wheeling. A smaller pulley should do the trick and still bypass at a safe pressure.
mombobuggy
Well-Known Member
- Location
- Highland
A smaller pulley on the pump will increase the pump r.p.m. s think about the gearing on a bicycle wheel . if you want your pump to turn more slowly go to a smaller crankshaft pulley commonly called a power pulley because it reduces the r.p.m. s of the accessories . also a larger pulley on the pump would slow it down as well. Orbital valves seem to need more pressure and less volume than a stock or modified power steering pump seems capable of producing. Rally cars have really neat pumps on them which produce less volume as R.P.M. s increase sort of like a snowmobile clutch in reverse. But they are not cheap I have not taken the plunge yet.