Explorer PS pump bleeding tip

[Viperwolf1]

I have my 5.0 in and am working to get everything hooked up. I got the PS system plumbed and added fluid but it only took about 1 pint. I knew there was plenty of air in the external cooler so I thought of a way to get it out. The pump has a 1/4" hex slot on the shaft so I disconnected the belt and grabbed the cordless drill with hex bit. I was able to get some air to burp into the reservoir but it was full of bubbles so I knew there was more. Then I grabbed the hand vacuum pump and attached it where the reservoir cap goes. I applied about 10" of vacuum and drilled some more. A lot more air burped out. I had the wheels off so I turned the ps box to full lock each way with the vac and drill on it and got even more air out. I went through this cycle a couple times and now have no more air bubbles when I use the drill alone. I was able to get a full quart of fluid in by the time I was done. The only reason I used the drill was because the motor is still a couple days away from firing. The same thing could be done with the motor idling.

 

[Broncobowsher]

We have fixed several air locked powersteering systems with a vacuum pump at work. We figured that you need a catch cup to keep the foaming oil from getting into the vacuum pump. We were using a vacuum pump for air conditioning, not a hand pump.

 

[Viperwolf1]

I didn't use a catch can because I couldn't find it. Didn't need it though, the fluid level was about an inch below the cap. The vac pump did a real good job of sucking the tiny bubbles out after you pour more fluid in too.

 

[Broncobowsher]

Vacuum pumps are great. I even used mine once it fix a cylinder head. A good vacuum will pull JB weld through porous cast iron (intake runner)

 

[bronco-billy-66]

Sorry for the long post:-X
I'm reserecting this old thread because I'm having a hell of a time bleeding my explorer pump. I just installed explorer serp and an astobooster, and a large plate style cooler. I've got the lines routed like the diagram I found here on CB. I've got zero pwr steering assist and zero pwr brake assist. I've gone through every bleed process google has to offer.

With the pitman disconnected and the engine off when I cyle the wheel I can hear air bubble in the sector or the booster, it sounds like the just move back and forth depending what way I turn the wheel.

I disconnected the line from the cooler to the res. and cranked the motor over,fluid pumps out.. so I guess that means the pump is working?? I've cracked the lines at the booster and the pump.. fluid seeps out.. I've removed the plugs in the top of the sector that are for later ram assist.. fluid comes out..
I really feel I've got a large bubble trapped in the system because with the engine off, the fluid rises and falls 1-1/2 to 2 inches in the res when I cycle the wheel..

Seems with the engine running the wheel is easier to turn when I press the brake?:??:?

I'm open to suggestions, Thanks

 

[Steve83]

If you have a liquid separator that can handle the pressure, you can use manifold vacuum from the idling engine to do what this TSB describes:

 

[72Sport]

The mid 80's Mustang Chilton's manual says use a vacuum pump and not to use manifold vacuum to get air out of a power steering system. The seals in the ps pump will allow air to enter the pump if the vacuum is too high. I made up a system to evacuate air using an old propane bottle and an air powered vacuum generator. I made improvements after the pictures were taken. I start the engine and let it run until I don't see any bubbles in the clear line.

 

[ransil]

I tried the vacuum thing ( uses a racket court ball with a tube thru it) along with a hand and electric vacuum pump, that did not work so I ended up disconnecting the hydro-booster from the system and bleeding the PS box first then put the hydro-booster back in and bled it out and everything was good within in an hour, before that I had many hours in it trying to bleed it.

 

[bronco-billy-66]

The mid 80's Mustang Chilton's manual says use a vacuum pump and not to use manifold vacuum to get air out of a power steering system. The seals in the ps pump will allow air to enter the pump if the vacuum is too high. I made up a system to evacuate air using an old propane bottle and an air powered vacuum generator. I made improvements after the pictures were taken. I start the engine and let it run until I don't see any bubbles in the clear line.

I made an apparatus today at work to try the vacuum bleeding. Maybe my kids will let me try it today.
For what it's worth, the pump hasn't made a sound yet. That, I don't understand, if it has air in it.

 

[bronco-billy-66]

I tried the vacuum thing ( uses a racket court ball with a tube thru it) along with a hand and electric vacuum pump, that did not work so I ended up disconnecting the hydro-booster from the system and bleeding the PS box first then put the hydro-booster back in and bled it out and everything was good within in an hour, before that I had many hours in it trying to bleed it.

I hope it doesn't come to that. But I may end up doing that. When I went 4x4x2. I had a hell of a time bleeding then too. No like this though

 

[72Sport]

I did a similar thing as Ransil. Before I even tried to run the engine I removed the return line from the ps box. Put the return hose in a 2 liter clear soda. Put a vacuum cap on the return inlet to the pump. Filled the ps reservoir and jogged the starter with the ignition switch. I had also disconnected the coil wire so it wouldn't start. I kept the reservoir full and jogged it several times until I had no air coming out the return line. Hooked everything back up and no more problems. Once the air is well mixed with the fluid vacuum seems to be the only thing that works. The flushing of the system gets rid of any junk from the inside of the new hoses and the ps box.

Another thing that may make it difficult to remove air from the system is the mounting position of the hydro-boost. If the lines enter and leave on the top side the air doesn't get trapped in the hydro-boost. The return line to the pump acts like a brake bleeder and continually pushes the trapped air to the ps pump where it is vented. Even with the hoses exiting the side can cause trapped air problems.