Steering Pump and Seals

[Alexio Auditore]

Power Steering pump changed, new lines, and vacuum pump re-sealed! It was not bad, just intimidating to start. A little tight getting to things too, but all and all, it was pretty simple and straightforward. Looks nice and clean too...

    So I have a question, I went for a drive, and the powersteering seems a bit on the weak side... and it groans a bit on turns too. This is a brand spanking new borgeson pump from genos garage. And I bled the crap out of the lines with the old pump, using 3 quarts or more of new fluid getting the old out. And new lines plus bleeding put a little more before reconnecting the return line from steering box to pump.

   After buttoning up everything, had it on stands and got air bubbles out of the system and.... Yada yada yada. ... should I give it some time to see if maybe there's a little air still trapped in the lines? How difficult should it be to turn the wheels just sitting on the ground not moving? I just want to make sure that this pump is not a problem from the get go ya know?

[Tractorman]

It is likely that there is air still entrained in the system.  Even after the initial bleeding of air, there is still lots of air trapped in various parts of the system - hoses, steering gear box, the brake booster accumulator , etc.  The flow rate of the power steering pump is about 2 gallons per minute.  The whole system only holds about one gallon of fluid, so that means that all the fluid circulates through system in about 30 seconds.  I am just using round numbers here, but you get the idea. 

 

Once the engine is started, the fluid and air immediately mix and both are carried rapidly through the system.  The only place for the air to separate from the fluid is when the fluid enters the reservoir and slows its velocity enough to allow for the air bubbles to rise to the top of the fluid and escape.  When the fluid is cold, this separation takes longer and a lot of the air is recirculated back through the system.

 

When I change power steering fluid, after the initial bleeding I start the engine and shut if off almost immediately giving the aerated fluid entering the reservoir a little time to release the air.  I do this a few times allowing the engine to run longer each time.  While the engine is off, I completely discharge the accumulator by stepping on the brake pedal several times (air can be trapped here).  Eventually, with the front axle on jack stands, I steer from stop to stop using the same procedure.  During this whole operation I frequently check and top off the fluid in the reservoir.  I then drive the truck to get the fluid to full operating temperature which helps get the remaining air separated from the fluid.

 

Regarding the power steering feels weak problem:  I have had three power steering pumps on my truck through its life of 340,000 miles (I am the original owner).  The first one did not fail - I replaced it at 215,000 miles with a new Borgeson just as a maintenance procedure.  In hindsight, I should have kept it.  At 290,000 miles the Borgeson pump failed.  I replaced it with a Napa remanufactured pump along with a Napa custom ordered remanufactured quick ratio steering gear box.  All is well so far and I really like the gearbox.

 

ALL of my power steering pumps in my opinion are NOT heavy duty and are not adequate for the heavy front end of a Cummins powered truck .  All of them could be stalled at idle with foot on the brake and steering hard to the left or the right before reaching the steering stop.

 

Just one opinion,

 

- John

Edited May 9, 2020 by Tractorman
clarification on the last sentence of the fifth paragraph

[dripley]

I am blessed. Still have the oe at 500k. But it seems to have an on again and off again leak. Mostly off. Had to fill about 3 months ago and then again a month later but now 2 months after that I have not added anymore. The only time I have touched that pump is when I resealed the vacuum pump a couple years back. I took it off the vacuum before removing the vacuum pump and never opened it up.

[Tractorman]

@dripley, it seems that you and @Mopar1973Man made the right choice in keeping the OEM power steering pump.

 

- John

Edited May 9, 2020 by Tractorman

[dripley]

8 minutes ago, Tractorman said:

@dripley, it seems that you and @Mopar1973Man made the right choice in keeping the OEM power steering pump.

 

- John

It has surprised me some of the oe things that are still on my truck.

[Tractorman]

Likewise... I still have original OEM front wheel bearings, rear axle bearings and seals, wiper motor, evaporator core, right tie rod end, front and rear antisway bar bushings, brake booster, brake master cylinder, clutch master and slave cylinder -  just to name a few.

 

I think the quality of build peaked in 2002 - the last of the Second Generation.  This motivates me to keep my truck.

 

- John

[Alexio Auditore]

Thanks for the replies. Ill give it a little time to get the remaining air out of the system. I didn't get it up to operating temp, so I'll give it a week or so and let you know if something changes or not. Next is the heater core....yaaaaaay. shouldn't be to bad. I'm excited to just get things checked off the list.