Question on valve springs

I recently bought a 73 Ford L-series with a 331 gas engine. The truck has been idle since 1976 with 15,000 miles. The engine still turns but I have not tried starting it yet. I was concerned about valve springs being compressed for 45 years. Should I pull the heads and change the valve springs? Also, what about sodium filled valves? Should I toss those as well, if it turns out the engine is equipped with them? I know those in the racing circuit never liked them, and I wonder if they caused trouble to any extent in stock applications. Would like your opinions on this. Thanks, Fritz

On most engines I build the spring test out as reusable. You can buy a spring tester that works in a vise. Without a spring tester no way to tell the spring pressure.
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I doubt the springs will cause a problem. As for the sodium filled valves. Just leave them be. In air craft engines they were for cooling. I guess they were used for the same purpose in car engines. In school were were told never to cut one open. I don't know why any would would want to do that. Stan

A 331 does not have a lumpy camshaft and it does not operate in the high RPM range so valve float is not going to be an issue either.

Not likely it had very high tension springs from the factory, with the mileage that is on it I would leave it alone and see how it runs.

What problems are you expecting the sodium-filled valves to cause (other than extended valve life)?

I agree with the others, fire it up and see how it runs, there should be no problem with valve springs. We ran sodium valves in our line truck fleet, my entire career as a mechanic, 331, 361, 391 engines, until we went to diesels, and they worked fine.

I would shoot some oil in the cylinders to lube the cylinders and start it.

Well being and OLD Ford mechanic/ TECH that worked on them OLD engines since it is a 331 and NOT a 330 then yes it has sodium valves as all the H D engines had , they were used for the Heat generated . Only problems i ever had with any Ford valves in H D app. was with one company as they ran a fleet of Ford Tandem and Tri Axles DUMPS local and back then the required fuel for the OLD gas powered trucks was HIGH TEST of 105 or greater octane . Sohio gas there high test was called Boron with valve cleaner and it did a fine job of cleaning valves . some weeks Pualey had two down . He ran the 391 H D as the smallest up to the 534. The Boron did not discriminate as it ate them all . Till i got him to switch gas then the problems went away . As for your valve springs i personally would not worry about the springs as much as rust on the valve stems and in the guides . The sodium valves have larger stems . YOUR big worry will be the Carb and gas to run it on . Carb problems will be the Power valve and the acceleration pump , they do not like gas with ALKIHOL .I can not remember every little detail of the tune up spec.s since the last one i worked on was like fifty years ago.

I would not be concerned with the springs. More concerned with starting it up dry and possibly stuck valves.

Put a few squirts of oil in each cylinder, leave the plugs so it can be blown out before trying to start.

Pulling the valve covers and oiling everything up will help, the gaskets are probably dried out anyway. Especially try to get some oil on the valve stems.

Turn it through and see if all the valves open and close and no bent pushrods.

As tractorvet said, expect fuel system problems. The carb will need a kit as the diaphragms will be dried out and will cause internal and external leaks. The fuel pump, best replace it now than later. Same with all the rubber hoses. Removing and cleaning out the gas tank will most certainly need to be done if it was left with gas in it.

Brakes and tires will also be needing attention.

Sodium filled valves a plus for a work motor.
Like others, I would be worried about parts turning with no lube, especially the cam lobes. Shouldn't be hard to rig something to turn the oil pump with a drill and prelube before starting. Also squirt some oil in the cylinders and turn by hand.

The springs should be fine for what rpm that turns. Although fwiw I did have a 292 chevy out of a grain truck where it did have weak valve springs. I swapped on some used ones from a small block and got rid of some uneven running. The old ones, you could push open with your palm without much trouble. The new ones were a lot harder to push. I'm real scientific with my push-on-it-with-your-hand method.

Thanks for all the replies, I see now where I should have been clearer. I was not concerned about valve float, since I will be the only one driving it, but was worried about the fatigue factor, and the spring breaking and allowing to t to he valve to drop into the cylinder. As for the valves , I used to hear about them breaking occasionally. Funny the Vet should mention tandems, cuz my dad had 2 T850s in the 60s til about 1978. We changed the motor in both of them at least once but I dont know too many details about the failures as I was pretty young then. So I cant say for sure the valves were the problem. Anyway , thanks again . Fritz

" the spring breaking "

Have you looked to see if they are rusted from moisture and residual combustion byproducts(acids) inside the engine while it was unused?

In my experience, I would worry more about them eventually breaking if they are rusty.

Back when I had heads reworked, the machinist would pop the springs and sit them all side by side on the work bench, Any saggers were easily recognized. I agree with your concern in having one compressed for that long vs one that was in the relaxed position.