On my 79 f150 4x4 when I jack it up and try to steer the pump resivoir completley drains. If you add fluid while the truck is running the steering works. But when you shut the truck off that fluid you added pukes out of the pump resevoir. Also the fluid is very frothy. Any ideas? Thanks.

 

the only time my has every yakked it's power steering fluid is when I over filled it once. Make sure you fill it just enough. Too much and it will spray out.

 

Never steer a pre-'97 Ford with the engine off - the steering box isn't designed to work that way.

You have to purge the air from the system to keep it from burping. Let the engine idle, top up the fluid, & steer all the way to one side. Top up to the level indicated on the dipstick. Steer all the way to the other side. Top up. Repeat until you can make 3 complete cycles without needing any fluid. Put a drain pan under it & turn the engine off. It shouldn't burp, and the froth should disappear in a few minutes. After that, it should be fine until you steer with the engine off again.

If that doesn't work, read this:

 

I read in another forum to steer it with the engine off? I tried toping it up as my dad was steering and at soon as I shut the engine off the fluid went all over the place.... Even tho it was correct on the dipstick

 

I looked this up in the Haynes manual and it says to do that whole procedure with engine turned on. It also says to check the power steering hoses and connections for leaks. Just a thought, but if it only leaks when the truck is off it could be because there isn't pressure when it's off like there is when the engine is running.

Are you leaking from the resevoir itself or is it coming from some place else?

 

That's exceptionally UNlikely, but I have diagnosed & repaired 2 Hondas with a similar failure. These truck's can't do the same, though, so what you're describing is virtually impossible.