I need a measurement PS related

[tutone]

Hey guys. Hopefully someone knows this off the top of their head. 1971 PS box , factory of course. The return line orifice is a NPT female flare. I need to know if it is a 7/16 or 1/2 inch thread. I have attached a photo of it with a tape measure across it. I am not a pipefitter, so Im not sure what the female should measure.

[RustyPile]

NPT and flare are 2 different types... NPT = National Pipe Thread. There are no NPT threads anywhere on the PS "plumbing". The return fitting is a 3/8" tubing with an inverted flare nut. It looks like the brass flare seat is missing from the box's return fitting.

[tutone]

Thanks. It makes sense. I had a short piece of brake tubing flare 3/8 that threads into the pressure side. I guess I will keep looking till I find something to work.

[RustyPile]

Originally Posted by tutone

Thanks. It makes sense. I had a short piece of brake tubing flare 3/8 that threads into the pressure side. I guess I will keep looking till I find something to work.

What you need is to replace that missing flare insert. They're readily available. A flare fitting is the only thing that will work. Brake line will work just fine for the return line fitting. I recently installed power steering on my '71.. I had a lot of trouble getting the correct hoses.. Never did find a return hose, so I fabricated one.. I took a piece of 3/8" double flare brake line about 8 - 10 inches long. Cut the flare off one end and used a double flaring tool and put a "bubble" on the cut off end. As close as it would fit in a tubing bender, I put a 90* bend in the other end.. I then bought some bulk return hose and a couple fuel injection hose clamps.. Looks almost factory and everything works fine.

EDIT I looked up my receipt for the pressure hose. Edelmann brand part # edl-70911... It's for 75 - 78 4X4, but fits '71 2WD just fine.

[tutone]

Will do. I have some 3/8 brake line. I will get there frome here. Thanks for your help.

[MikeB]

Originally Posted by RustyPile

I recently installed power steering on my '71.. I had a lot of trouble getting the correct hoses.. Never did find a return hose, so I fabricated one.

I went through hoses from several "manufacturers" only to find the bends were almost identical and nowhere near OE. Ended up using a tubing bender to allow the tubes to clear the frame. My pressure hose was a very tight fit and needed persuasion to get it at the correct angle to connect to the pump.

If I had a do-over, I might bite the bullet and use braided hoses with flare to -AN adapters.

[RustyPile]

Originally Posted by MikeB

I went through hoses from several "manufacturers" only to find the bends were almost identical and nowhere near OE. Ended up using a tubing bender to allow the tubes to clear the frame. My pressure hose was a very tight fit and needed persuasion to get it at the correct angle to connect to the pump.

If I had a do-over, I might bite the bullet and use braided hoses with flare to -AN adapters.

Stainless w/-AN adaptors wouldn't fit in my case.. Not much room at the rear of the pump, the headers were in the way. The irony of the ordeal was that I didn't like the way the headers fit overall, they interfered with everything.. Several months after the power steering install, I finally removed them and refitted cast iron exhaust manifolds... I don't have any pics of the final install.

Here's a link to some illustrations of the hose I used. It crosses the frame in front of the pump, drops down and runs under the pump. Then straight up to the pump pressure fitting.

https://www.bing.com/search?q=edl-70...ANAB01&PC=LCTS

[A1971Blazer]

Inverted flare...as mentioned, the brass insert is missing
one is 5/8-18
the other is 11/16-18