bleeding power steering system
 

Like the title says, what is the best way to eliminate all air from a power steering system? I installed an AGR box, rebuilt pump, and new hoses and followed the instructions (jack truck up, turn wheels lock to lock at least 20 times, crank engine for two minutes) but I think I still have air in the system.. At idle, it works okay, but if revved slightly, I can feel a "shuddering" in the wheel as I turn it that feels like there might be air in the lines. Also, the wheels turns more freely to the right than the left, not sure if that is significant but just thought I would add it.
I have tried revving the engine and turning the wheels lock to lock, and while the truck was jacked up it was fine, but once on the ground it still has that weird shuddering when I turn the wheel. No squealing, just a noise like air bubbles in a line. All lines are sealed well, I chased down all the leaks already. Would this be air in the system or something else?
thanks in advance,
John

It's like most hydaulic systems, in that as you excersise it, it will introduce air into the sys. until it's completely full of fluid. Let it set overnight, and check the level in the morning. Top it off and try it again. Most or all of the air in the fluid should have dissipated overnight. Had to do this to mine, as it acted the same way when I filled it for the first time. Now, it works fine. Hope this helps?

:flag: :gmc: :burnout:

Thanks very much Dan, that helped a lot. I will go recheck it this morning.
John

Be sure belt is tight-will slip and make the steering wheel "shudder".

You can turn the steering wheel with the truck running in park all the way to the right then all the way to the left several times. It should get the air out of it. good luck

Turning the wheels while the engine is running will cause the fluid to foam. The foam must be alowed to settle out, usualy about 1/2hr will suffice. Then add more fluid to fill again. I tend to agree with jhow66, about the loose belt. That will cause the shuddering. Low fluid causes a whining noise and makes the steering hard to turn. WES www.ClassicHeartbeat.com

When I replaced the pump in my Camaro, it was as if I had no power assist intermittantly. I guess I was an idiot, because I drove it that way and it just worked itself out. I did just what you did though, turned it lock to lock many times but only time made mine work like it was supposed to. Obviously if you do what I did, be VERY careful, it can make for some very dangerous driving with the power assist seemingly coming and going.

I think I finally got it all out, it runs really nice now, very responsive. I still have a weird thing with the wheel turning more freely to the right than the left. If I make a left turn, the wheels will recenter as soon as I let go of the wheel, but when turning right, I have to manually turn the wheel back left to straighten it out. I guess I will try greasing the suspension tomorrow and see if something is binding a bit. It is not a tire pull. Any ideas?

you can use vaccum to get the air out of the system

Do you notice it taking any more effort to turn to the right than the left? If so it may be an alignment issue. Last resort it could be a problem with the box.

It takes more effort to turn the wheel left. It is not alignment, because it feels the same way when the truck is up on jackstands.

I would suspect the box then, most likely a problem with the spool valve. Call the supplier.