power steering bleeding.

[tekkatekka]

I have 1991 Ranger, 4x4, 4.0 engine. I removed the gear box and power steering pump. About to install rebuilt pump and gearbox and new lines.
What do I need to do about the ATF fluid. Do I need to add any to the gearbox before installing or the pump. What to do to bleed it after install? Thanks for any help.

 

[mikkelstuff]

Ford power steering pumps can be noisy. An old Ford friend gave me this advice which works.

It's how you bleed the pump that makes or breaks the noise problem. Those pumps are finicky sob’s about getting any air in them.

Most of us start the engine and try to keep up with the fluid level while the system purges itself. WRONG ! OK, those pumps are kinda noisy even at best but if you only spin the pump at the speed the starter turns the engine, you don’t run the pump dry and get that nasty whine.

Jack the truck up in front and set it on stands with the front wheels off the ground. DISABLE the IGNITION so the engine doesn’t fire up when you crank the starter.

Now fill the pump reservoir and crank it just enough to make the fluid level go down. Repeat filling the reservoir and cranking until the fluid level stay’s full.

NOW you can start turning the steering from side to side and filling the reservoir as needed. When the fluid level goes down stop cranking and add more fluid.

Remember to give the starter some time to cool off once in a while while using this method.

You should be happy with the results from bleeding your steering with this method.

IF your pump is already whining, this method isn’t going to help you as the mating surfaces inside your pump are already damaged.

 

[Shran]

If I'm replacing the steering box, I fill the reservoir and with the front wheels off the ground, turn the steering wheel back and forth lock to lock about 20-30 times. Then start the engine and do the same thing, while watching the fluid level closely and paying attention to noise. That's basically what the instructions that come with new steering boxes say as well.

If it's just a hose or the pump that I'm replacing, swap the parts in, I fill the pump and fire it up. Drive around the block a few times and top off fluid if needed. Not much risk of running the pump dry in this case.

 

[gw33gp]

I can say the advice you have received so far is good. I replaced my power steering pump and hoses. I looked up the Ford recommended procedure and the only thing I can add to what has been said is pull vacuum on the reservoir when turning the wheels back and forth. If you have no noise without pulling vacuum, you should be good to go.

I pulled vacuum as Ford recommends and have no whining at all. I don't know if it would whine without vacuum.

 

[tekkatekka]

I can say the advice you have received so far is good. I replaced my power steering pump and hoses. I looked up the Ford recommended procedure and the only thing I can add to what has been said is pull vacuum on the reservoir when turning the wheels back and forth. If you have no noise without pulling vacuum, you should be good to go.

I pulled vacuum as Ford recommends and have no whining at all. I don't know if it would whine without vacuum.

Thanks, how did you pull the vacuum and with what?

 

[Shran]

You can put a barb fitting in the reservoir cap and use engine vacuum or use an AC vacuum pump if you have one. I've never done that but it definitely can't hurt.

 

[tekkatekka]

You can put a barb fitting in the reservoir cap and use engine vacuum or use an AC vacuum pump if you have one. I've never done that but it definitely can't hurt.

Wouldn't the vacuum pull some ATF into the engine?

 

[Shran]

Wouldn't the vacuum pull some ATF into the engine?

Shouldn't. Fluid should be an inch or two below the cap and it drops somewhat below that when the engine is running. The engine doesn't make enough vacuum to pull fluid that far up.

 

[codylink]

I'm bleeding my system now. I didn't have a vacuum bleeding method so I came up with this beauty using my fluid extractor and some closed-cell foam. My wheels are on ramps too so I can't turn steering back and forth like was suggested here.
Here's the method I'm trying based on instructions from my new steering gear:
1) Fill reservoir with return line disconnected
2) Turn pump by hand (belt removed) to flush clean fluid through system
3) Reconnect return line
4) turn pump by hand and top up the level until it stops dropping
5) Use my special vacuum system to pull and air and top the reservoir up
6) Repeat 4 and 5 until no more air

Next step I guess is to put the belt on and start it up.

Anybody have strong opinions on whether it's going to work?

 

[BlackBII]

I use a large syringe to pull a vacuum and it works great. If you add a vacuum line check valve you can pull a vacuum and then remove the syringe without losing your vacuum. I do brakes and clutches this way as well and it works great.

Home Depot and Ace Hardware have rubber stopper plugs that'll fit in the reservoir and you can drill a hole in them and insert a barb fitting.

Also, these pumps use Type F fluid. Anything else and they'll whine.