Engine: Is the Stude V8 a non-interference engine?

[Lark Hunter]

I'm in the process of cleaning the fuel system on my '62 Lark after some gasoline went bad sooner than expected, and decided to do a compression test while I have the carburetor off. To my surprise, two cylinders had no compression... and it was firing on all eight when it was last parked a little less than a year ago. I traced it down to a couple of slightly gummed up intake valves that aren't quite closing in time for the compression stroke. There's a big puddle of sticky brown schmoo in the intake, right under the carb, but none of it migrated down the runners. Am pretty sure the valvetrain will free up once I've got it running (I've been here before with other engines), but just wanted to be sure pistons and valves won't try to occupy the same space at the same time when it first fires.

[StudeRich]

I would not take a chance on a Valve hitting a Piston. Pull the Valve Covers, tap the valve end of the Rockers with a Brass or Plastic Hammer and free them.

I would use an Oil Can to squirt some Marvel Mystery Oil or ATF on the Valve Stems first.
You have TWO stuck Intake Valves, so you need to free them and find out if anything else is wrong with the Valve Train before firing it.

Taking the easy way out could lead to expensive damage.

[GrumpyOne]

I'm in the process of cleaning the fuel system on my '62 Lark after some gasoline went bad sooner than expected, and decided to do a compression test while I have the carburetor off. To my surprise, two cylinders had no compression... and it was firing on all eight when it was last parked a little less than a year ago. I traced it down to a couple of slightly gummed up intake valves that aren't quite closing in time for the compression stroke. There's a big puddle of sticky brown schmoo in the intake, right under the carb, but none of it migrated down the runners. Am pretty sure the valvetrain will free up once I've got it running (I've been here before with other engines), but just wanted to be sure pistons and valves won't try to occupy the same space at the same time when it first fires.

Today's lousy gas is a prime danger for sticky valves should you leave your car stored for more than a few months. The result can be bent push rods on the intake side of each cylinder. This happened to me TWICE on the Power Hawk and in both cases, I had to remove the heads and intake valves to free up the guides. The engines could be started by it sounded like the rattles of death until it warmed up... That's how bad it can get.

As to your first question... I do not believe that Studebakers had interference engines.

[jclary]

If these engines were interference type engines I would have exploded one all over the interstate in the late 1980s when my 259 powered Lark's cam gear decided to shred its teeth at 80mph on the interstate! That's when I learned how true the word ass-u-me is often broken into three parts when you assume that you can trust a tiny little oil pressure light instead of a gauge is a sufficient indicator of good oil pressure?

It became a great platform for educating myself on how to remove, dismantle, rebuild/overhaul, and reinstall a Studebaker V8. In that process, one of my greatest challenges was learning what tasks I could perform myself and what items needed to be taken to auto machine shops for repairs beyond my skills. The mere fact that you asked the "Non-interference" question is an indication that you have the curiosity to read and learn. Which means you are teachable. I hope your learning experience turns out not to be as extensive or expensive as mine.

But, I also hope it turns out to be as beneficial and enjoyable as mine.

[shifter4]

A while after Dick Datson and I were finished with the V4 conversion interlude , I converted the engine back to V8 config. , and
not too long after that , the engine stripped the fiber gear one afternoon .
I rolled to a stop , and shortly noticed that the engine turned with the starter , but the rotor did not .
That confirmed that the gear was trashed . The engine had a lot of miles on it before going to 4 cylinder operation , and I feel that
a lot of extra wear and oscillations occurred during that time of 4 cylinder. operation .
I later replaced the gear etc. , and motored on .
Stude V8 is not an interference engine .

[PackardV8]

As mentioned, the Studebaker V8 is not an interference engine. While valves won't hit pistons, the potential for damage comes when a valve sticks closed. Turning the engine with the starter or by hand can break the fiber cam gear, bend pushrods, can break rocker arms, can damage the cam and/or lifters.

jack vines

[rockne10]

Today's lousy gas is a prime danger for sticky valves should you leave your car stored for more than a few months.

This is why I add a few ounces of Marvel Mystery Oil to every ten gallons, or every time I fill up.
Gas or diesel, large or small, there's a reason why farmers have been putting MMO in their tractors for the past hundred years; and especially important now that there is alcohol in the gas.

[Lark Hunter]

Thanks everyone for the information; I certainly appreciate it! I have the valvecovers off, and am able to open individual valves by leaning into them; the two sticky ones open and close without too much extra effort, too, but the stems have just enough gummy stuff to slow down their return to seat. No valvetrain components are bent or broken, and my plan is to do what I can to get some solvent and lubricant down into the valve chambers. That would also be easier if I had the engine at least running at low idle, so it'll be easier for it to "snarf" aerosol the carb cleaner (dissolves the varnish quite well) down where it's needed. Once I get this cleared up, having yet another reminder of gasoline's often short and unpredictable shelf life... should be extra encouragement to keep my car on the road and drive it more.

[Lark Hunter]

assume that you can trust a tiny little oil pressure light instead of a gauge is a sufficient indicator of good oil pressure?

I really do want to keep my car stock, but this is one of the few areas I will make a minor alteration... Of course that particular gauge assy with the warning lights in my 1962 switched back to having a real oil psi gauge and ammeter for 1963-up. One of those later style once will make it onto my car; the exact same thing I would have done if I had purchased a new '62. Also, a good reminder to check out and clean the oil psi relief valve, to make sure that cam sprocket is getting good lubrication.