I've added a remote power steering reservoir and one of those small GM pumps. I'm getting a whining noise from the pump. I used #6 braided hoses on all the hookups to and from the pump,gearbox, and reservoir.
It has been suggested to me that maybe the return(low pressure) hose is too small on the inside diameter. Am I getting cavitation because the return hose is not getting enough volume to re-supply the pump with fluid?

I'd say your reservoir to pump inlet hose is the problem. You need to feed the inlet of the pump with 1/2" minimum ID hose (-8). Your current -6 suction hose is most likely the the cause of your whining pump. The reservoir also needs to be mounted higher than the pump to "gravity feed" it. The return from the box to the reservoir can be -6.

You also need to make sure the reservoir to pump inlet hose can take at least 20" of vacuum, otherwise the suction of the pump will collapse the hose. Most braided hose will take 28" of vacuum with no problem.

Troy

Paul...I'm working on a march serpentine conversion which includes a remote reservoir type setup. They sent along a set of braided hoses, with what looks to be a -10 for the reservoir to pump connection. -6's for pressure and from box to reservoir. So this pretty much confirms what Troy already passed on.

One other thing you may want to look at is in the remote reservoir. Mine has two fittings on the bottom of the can. One has a nipple on the inside of the can, which is supposed to be used for the return from the box. The one that goes to the pump has no nipple, so it's lower than the return, and will hopefully not suck air. If you have something similar, and these are reversed, it might also cause a supply problem.

Good luck!

I think you will find that nearly all GM pumps with a remote reservoir use a 5/8 inch ID suction line from the reservoir to the pump. The low pressure return line from the gear to the reservoir is 3/8 inch ID. Pressure from the pump to the gear is also 3/8 inch ID.

It has been my experience that long suction lines or lines that are smaller than 5/8 inch ID can starve the pump and cause airation of the fluid.

Troy, Bob, Jim,

Problem solved. Bought 2 ea #10 Ni-Coat 90 degree fittings and 18" of #10 braided hose from Earl's for $78 bucks. No more whining. Yes, the pump was starving for volume.

Isn't this a great site!

Paul....glad you got your problem solved! I've got mine plumbed now, and hopefully in a week or so will be able to fire up the car and see how it works... smile.gif