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So I did a little research here on the bolt and I couldnt find the thread that I was looking for. I am sure someone has talked about power steering on these old rigs before. If someone could point me in the right direction I would appreciate it.

My truck has lines and some kind of cylinder in the steering. Some of the lines are missing and there is no pump. I was hoping someone had a schematic or diagram of how the plumbing ran on these big dogs. I read somewhere that these are steering assist and not a true power steering setup. I dont know what that means or if its even true.

Also, can I just run any old power steering pump?

Truck is a 59 Spartan 100

Thanks

Hy Spartan, the factory power assist steering involved a control valve in the drag link and I believe there may have been two different types. Does your drag link have a larger area with ports in it close to the Pitman arm?

It was called "Power Steering" when new...most people now call it power assist (hydraulic cylinder attached at the frame and the tie rod).

The Power Steering Pump was attached to the back of the Generator originally.

Mike B

3B, sorry but I'm an idiot and I don't know what a drag link is.

Mike. I knew it used to be off the generator. But can I just hook a newer model pump up off the belt and plumb it in?

Hy Spartan, the drag link is the piece of the steering linkage between the pitman arm on the steering box and the third arm on the top of the left spindle, hope that helps.

I guess you could as long as you match the original hydraulic system pressures.

Mike B

The same type of system is used on the 1963 - 1982 Corvette although with lighter duty parts no doubt, I rebuilt mine (on the Corvette) and all the parts are still available from many Vette suppliers. If you can't find big bolt parts then I bet you could make something work. I don't remember seeing a generator/pump combo on the early ones but mine has the traditional Saginaw divorced pump/reservoir.

Here's a couple picture of my 1956 9200 with factory power steering. The pump is on the back of the generator and the control valve is incorporated in the drag link.

Mike B

Hy Mike B, thanks for the pictures, as they say "one picture is worth a thousand words".

Hey Spartan. Good luck on that steering pump.
On this power steering/assist steering subject, fellows, what is the conventional wisdom
on the issue of , in the case of a fluid pressure failure, what happens?
I would guess, or hope that the default position of the valving allows free movement of the oil in the loop.
Thereby allowing steering in any situation, even if stiff. (I mean the steering)
My ‘54 GMC 450 firetruck, is armstrong steering, and I would consider this system if I felt it was safe and not
an archaic dinosaur rig.
My wife is driving it, and neither of us is getting any younger! And I won’t go to the obvious follw-up joke.😁

My 69 T50 fire truck has the "hydraulic steering" option on it, similar to the pictures above but bigger parts. It has the big steering wheel as if it had manual steering. With the engine off it is a bear, if you are stopped it is very nearly impossible to turn the wheel. That however is not a safety issue, if the truck is stopped. With the truck rolling, even a little, it is quite easy to steer and certainly could be pulled to the side of the road safely. I have no worries about the steering failing and not being safe.

I have been driving mine around for a while without a pump. The steering doesnt feel abnormally stiff or weird. Its just like any other rig without power steering. As far as I know its not dangerous and nothing bad has happened. Now if you lost all your fluid and ran that pump dry for a while that might be a different story...

Hy Steelonsteel, the system is designed to allow steering if the hydraulics fail.

Saginaw steering on trucks up to one ton are common and be used with for and aft drag links and port and starboard drag link. Saginaw makes larger gear that are
used on 1.5 to 3 ton trucks, larger, double steering gear with similar pump. Should work well with larger truck. Check midsize truck's gear for compatibility.

Probably would be better choice that trying to make antique steering system work.

Ed

Thank you, fellows, for the input on this steering system situation.
And to Sparton for bringing it up!

On the 3 '67-72 GM C50 trucks I have owned, the PS pump was v belt driven off the crank pulley, the PS hoses went directly to a hydraulic ram assembly that incorporated a spool valve, one end of the ram attached to the tie rod and the other end was bolted to the front beam axle. Movement of the steering gear moved the spool valve which directed hydraulic pressure to the ram, reducing steering effort. Hope this makes sense, this system is as simple as it gets. If a loss of fluid pressure occurs, the steering effort is increased, but manageable. This system would be adaptable to about any straight front axle truck. The '55-57 Chevies had power steering pumps piggy backed on the back of the generator, later Chevies may have had the same system, I expect that the after market restoration houses can supply the special generator with a splined output to drive the special PS pump, big $$$$$ I expect. I don't know when they changed to direct crankshaft driven PS pumps. Crankshaft driven pumps are very common and inexpensive. Corvettes from the mid 50's up used a similar ram system for PS. I don't know if a Corvette PS rebuild kit would work for our purposes or not. Good luck!

Here are a few photos of the ram assist type p/s that we added to a 1940 International pickup. I would think the 55-64 car or up to 82 Corvette system would work on a driving unloaded only truck but a working truck would use the larger ram. On Sparton's truck the ram frame anchor and tie rod end eye for the ram should already be in place.

tapered hole for assist ram in tie rod
[img]https://i.postimg.cc/sBcFkxT0/straight-axle-p-s-002.jpg[/img]

ram bolted in place
[img]https://i.postimg.cc/4mZ6d3P1/straight-axle-p-s-005.jpg[/img]

control valve on rear of drag link---mounts to pitman arm. Upper hoses are the pressure and return to the p/s pump and lower hoses go to the assist ram (position specific).
[img]https://i.postimg.cc/DWVs9ySs/straight-axle-p-s-003.jpg[/img]

The engine is a Chevy V8 with factory belt driven p/s pump.

Nice installation. Obviously anyone who attempts this should be careful about the welding.

There is a pressure control valve in the ps pump that can be changed to alter the pump pressure. It is mounted behind the pressure outlet fitting of the pump. That fitting unscrews and the valve can be extracted and changed. I don't have any info on what valve does what but they are available if the pressure is not right to give the steering a proper feel.

That valve can usually be shimed for adjusting pressure and the size hole in it determines flow rate, can be exchanged for a smaller one for lower flow or larger (or enlarged) for higher flow.