91dime

This is for a 91 S10, I know it’s not a F body but the steering box is the same as a third gen. I always get good info and help from everyone here, so I like to ask here.

I have no power steering, at a stop it takes all I have to turn the wheels. When it’s moving it’s much easier. I have taken the weight off the truck and went lock to lock 20+ times. Check fluid and it’s always ok. Hoses are routed correctly, I have another working s10 to compare them too. I pulled the pressure hose and it is pumping fluid.

The truck has a 350 with a GM performance serpentine system, and the steering box is the original 91 s10 box. The pump and box have O ring to AN fittings, and Parker hoses. I even tried changing the pump once with no luck.

Could the steering box box be the problem? Its really the only thing I haven’t changed. I don’t know much about the inner workings of it. I would just change it out, but it’s not an easy change out.

Any thoughts or help would be greatly appreciated!

ironwill

Just because the pump is moving fluid doesn't mean it's OK; you'll need to test the pressure output with a gauge. I don't know what your specific spec might be, but a rule of thumb would be to see a pressure of somewhere around 1000-1200 pounds or so if the pump is good.

91dime

I don’t have a pressure gauge, I may have to get one to diagnose this then. I need to pull the relief valve and check it too.

ironwill

^^^^ That would be the logical next step, and might just prove to be your problem.

91dime

I removed the fitting on the pump, and there was no spring pressure pushing it out. After getting it out I had to poke in there and the plunger came out, as well as the spring. So I guess it was hung up one something, I didn’t see any burrs on the plunger. It should follow the outlet fitting out correct?

Edit: re installed the spring, plunger and fitting. Still no power steering. The truck has less than 200 miles on it with this issue, could the pump be roast from driving it with a stuck plunger?