pauldana

power steering pump,, rebuilt or new?
what is the best rebuilt unit out there?
best new unit?
is it worth paying more for new? or is rebuilt just fine...

just wanting opinions and inputs..

I run the ham can borginson. .... which powers both my rack and HB..

HeadsU.P.

I can not complain about the rebuilt from NAPA. Been 6yrs no issues.
They wanted a core exchange. But hang on to your old one first to swap-out pulley and keep your cap / dipstick.

Whichever pump you order, make sure its C3 specific. Not all Saginaw pumps have the same fill spout.
Some are tall spout. You need short, so the cap clears the ALT bracket when removing.

Use great caution when removing your pulley. You do not want the bend / warp the pulley.
Some are press-on, some are threaded.

pauldana

march aluminum pulley i have pulled on and off several time over the years...
red power-coated duel inlet return ham case for the HB



I know about those details...

just looking for a good reliable pump without issues.. a lot a junk out there as well as the good... probably more junk:-) lol

carriljc

I warped my ps pump assembly so I picked one up at Autozone. Been working like a dream for 10 years. Don't return the core until after you bring the rebuilt one home and inspect it. I had to transfer a stud from the old one to the new rebuilt one. Just make sure it all matches up and all. Now I have a Lifetime Warranty as long as Autozone doesn't collapse.

pauldana

truth

anyone know what psi it should be running?

Mooser

Have a look see here, posts 5 and 10
https://www.corvetteforum.com/forums...ring-rate.html


For what it's worth, the pump is a pretty simplistic unit, re-sealing is cheap and easy. What is it that's wrong with yours?
M

vtech

I also installed a rebuilt PS Pump last October from NAPA and it fit like a glove. No problems as of yet, yes, keep your dipstick/cover and make sure to inspect your hoses attaching to the Power Control Valve. Also, a good time to update your belts if needed. I found the installation to be very easy.

HeadsU.P.

Evidently, some store bought rebuild pumps come with the stud installation kit that is installed in the rear of the pump.
Evidently, some come with tiny "O" Rings that go in the bottom of the hole, under the stud.
Evidently, that hole is not a blind hole but rather protrudes into the reservoir? Don't remember.
Evidently, if you don't install the "O" Ring and some RTV on the stud threads, it will weep later on.

Somewhere on this forum was a drawing showing those "O" Ring locations.
Evidently, some pumps do not come with instructions about the tiny "O" ring.

Just sayin'. Beware.

4-vettes

I had a rebuilt pump on my car for about 20 years. When it died I replaced with a USA made Tuff Stuff unit. Really nice.

pauldana

I think my pressure is sub par... and it has no pressure reduction washers.. so it is not that...

I do not like to replace parts... lol:-). so this is why i am asking... i want to do it once, and done...

Mooser

I run the stock (banjo) pump with HB but without a borgenson, never had any issues other that heating the fluid more that you would think. (added a cooler and never had any more problems.)

Seems almost strange that the pump is weak, I would think it would take a tonne of miles to wear one out but maybe it's had a hard life.
Is the HB line returned properly to the pump res.? Tee or seperate fitting? I think that would affect the brakes rather than the steering though...

M

pauldana

both have independent return lines and ports.

Mooser

I should have known you'd have it right

According to what I can find:

Jim Shea
One thing to be aware of: The power steering hoses in the C3 Corvette steering system do not like high pressures. Most GM power steering systems operate at 1450 psi. The C3 Corvette system was designed to operate at a maximum pressure of 950 psi. For instance, do NOT take a flow control from a pickup truck and install it in your Vette P-pump. (The valve will interchange!) The high relief pressure setting will quickly cause your hoses to leak. You want to use the flow control valve from your original pump.
Post #2

Post 12 same thread
If you reach manual steering efforts before reaching full lock, then you need more pressure. In other words, you want to use the lowest pressure that will allow you to reach full lock.
The Corvette booster cylinder system requires only 950 psi. The Saginaw 600 integral power gear may require pressures around 1200 psi in a C3 Corvette with more modern bigger tires.
I do not think that the hydraboost braking system necessarily requires pressures over 950 psi. But I am not sure. I am quite sure that the hydraboost unit would have been validated at 1300/1400 pressures.

More info here in post #1
https://www.corvetteforum.com/forums...-overload.html

M

Mooser

Oddly enough, checking on the borgeson website, their GM power steering pump is Pump Pressure: 1200-1350 PSI

But you can buy the kit without a pump for SB and BB corvettes with power steering and it doesn't mention anything about the pressure only being 950 psi.....
M

leigh1322

Paul
Why do you think the pressure is too low?
What symptoms are you getting?
If you have getting 1200 or so I would think the PS is fine. PS really only hits max pressure when it is against the stops, with basically no flow. Usually the psi is far lower.
Low flow can cause it to "catch" especially in an aggressive manuever.

Flow orifices can actually be used for fine tuning:
post #21
https://www.corvetteforum.com/forums...ispreloading=1

OldCarBum

Before I decided to switch over to manual steering, I purchased a new Tuff Stuff power steering pump and a Billet Specialities remote fluid tank.
Top quality and made in the USA.

Tuna Joe

I bought a rebuilt pump from Lonestar in Texas.

augiedoggy

I bought the very inexpensive and easy to install rebuild kit for my pump when I swapped engines in 2012... I also purchased a chromed housing. I had far more issues getting the chrome housing to fit than I did rebuilding the pump. they are both still in my car today however.
I rebuilt my steering ram at that time as well.
I also rebuilt my alternator AFTER buying a new replacement and having issues with it... YMMV

pauldana

my rack and pinion is Steeroids, my braking is Hydro boost,
I am working on better balancing the 2.
I have been in contact with pure choice motorsports........ https://www.purechoicemotorsports.co...rod/prd365.htm
they claim that using max pressure (no pressure reducing washers) but reducing flow will better balance the system.

i believe my pump does not have much pressure until 1500rpm, as braking and steering is bad at idle, but great above 1500rpm... not acceptable. thus the reason for a new pump.

leigh1322

Ummm...don't know them... suggest you call Turn One Power Steering Systems...they are the experts, do racing, NASCAR, Sprint, etc. or Tom Lee, same.

Their tuning suggestions are that when it "catches" it needs more flow... (I have tested that myself also)

"If you get hard steering in the parking lot, the first thing to try is a larger flow orifice, since there is very little flow at low rpms. (At those speeds you are at low flow and low pressure). That could help the control valve build pressure quicker, and the pump to supply more power. The same thing is true during a slalom run. You need more flow. "

Hydraulic systems are madly mis-understood. There are two restrictions in the system, one upstream at the pump, and one downstream at the device.
You only have about 100 psi in the system hoses at idle without PS being called for, past the pump. But the flow is maxed out at wide open. Your system very likely has less psi than normal since you have two parts connected with two downstream "control valve" restrictions / leaks at idle. So you may have too little psi since you have a bigger leak rate / flow at idle. When the control valve in the PS shuts for example, (you turn the wheel) it cuts off the flow. Since the pump is a positive displacement pump, it puts out the same volume no matter what, and with no place to go the psi skyrockets. Your psi is not getting high enough, quick enough, so you need more flow at the restriction at the pump, then the idle psi is a little higher to start with. The restriction in the control valve downstream is the 2nd restriction. It's all a balance. But now you have two downstream restrictions / control valve / leaks at idle, versus only one before, = low psi.

If you go too high with flow, you will have too much psi at idle, steering will be too twitchy, flow too much, and make too much heat, that will be hard to get rid of.

I'll bet you never use more than 200-300 psi anyway unless you are getting really aggressive / violent with the wheel, like in a crazy quick & fast slalom. More psi is seldom the answer. More flow almost always is.

The 1500 rpm clue is another great clue, since your issues stop at that rpm. The pump is constant displacement, so more rpm flows more fluid with rpm. Still no psi until it hits a restriction. At 1500 you would have 2x the flow as at a 750 idle. So that clue is also telling you that you need more flow.

At "x" rpm, the pump flows more than the flow restrictor will let pass out of the pump, so the internal pump psi skyrockets, and pops off it's internal psi relief valve, and bypasses the flow internally. But it still flows 2.1 gpm and has maybe 100 psi outside the pump. If it stays in internal bypass mode too long, at full psi, the fluid overheats. If you restrict the pump flow too much, you run into that problem. That does not sound like your problem, or solution. It really should never make 1300psi, unless you hold the steering hard against the stops, completely blocking off the flow, of the constant output pump. Don't do that for long....

A even better a bigger flow valve is quick fix and like $30.

Unless you want to rig up a psi gauge and see if you have over 100psi in the hoses at idle?