Motor oil

I'm sure this has been over discussed but i need to ask. Been reading alot about motor oil for old orginal engines. I want to preserve mine as long as possible. The big question, zinc content? Does anyone run rotella conventional oil/10w30 or straight 30w in there original engines? I saw somewhere a 53 chevy required staight 20w? Too thin in my opinion but oil has changed over the years. I dont want to run synthetic but want to prolong my 235 forever. Any suggestions?

I've been running 10-30 in all of my gasoline engines for many decades. In the last couple of years I've been adding some zinc to my hotrods, [small block Dodge and Ford flathead]. The first 18 years that I owned the small block Dodge I never put an additive in it, and I don't think the previous owner did either before my ownership. I think that if you get a motor rebuilt you better be adding zinc religiously for a while, though. Good Luck.

The old school rule of thumb was 20w in the winter and 30w in the summer. The lighter weight oil made it easier on the starter in the winter.
I run 10w30 all the time myself.
Always use zinc additive every time you change oil. You'll be more likely to ruin a cam if you don't.
I absolutely do not like Rottela oil. Delvac is what I use in my diesels.

I know the guy that had my car before me just put anything cheap he could find in her. I let her run for about a hour last night with a can of sea foam in the oil to clean her out a little. Got an oil filter yesterday but havent decided on an oil yet.

The best kind of oil for a 60 year old engine is the kind that is brown and in the crankcase. It doesn't matter in the least. Nothing you do now is going to change the wear that has already occurred. Me personally, I run 15/40 or 20/50 in most of my old engines to keep the oil pressure up and the blowby down. Other than that, it's really not something to stress over. Unless you have a fresh rebuild, "picking" an oil is nothing more than personal preference. Some may disagree, but experience proves otherwise...

BED ^^^^ is correct
I'm partial to Valvoline 10w30
However this is like car manufacturers, everyone has their favorites.

They took most if not all of the zinc out of Rotella and the other diesel oils when they started putting the DPF's in the exhaust because it clogs them up over time. I've run Rotella for years, no problems with it.

I use Lucas oil stabilizer in everything I have except the two strokes. A quart in the gas burners, a gallon in the Cummins ISX diesel. Never lost an engine due to an oil breakdown running it.

I`ve used 20w50 VR1 Valvoline in my old mopars. I`d probably throw anything mineral and cheap in a chevy

Your right. 60+ years of anything and everything has already did the damage. But with 84000 miles and no smoke or blowby and great oil pressure, im going to run only the best to avoid the worst. Thats like i always thought premium gas was a gimmick, my equinox wont run on 89 octane.

53 stickfigure said:

Your right. 60+ years of anything and everything has already did the damage. But with 84000 miles and no smoke or blowby and great oil pressure, im going to run only the best to avoid the worst. Thats like i always thought premium gas was a gimmick, my equinox wont run on 89 octane.

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The tolerances on a brand new 235 were far from what they are on your Equinox, yet alone 60 years later. That's my point. You're essentially a step above a tractor. Change the oil every 3k like you're supposed to and it won't matter what you put in it. Use a decent weight and keep it clean. If you're that worried about zinc content then use Valvoline VR1 and get plenty. Still, if the engine goes, it won't be what oil you're using. Speaking of gas, one of the best things you can do with an old leaded gas engine is run a little 2 stroke oil in every tank. It is a good substitute for lead, fights off the effects of ethanol and will keep everything lubricated properly.

Been putting marvel mystery oil in the fuel, its probably just tranny fluid but about the same price at walmart. Went ahead and ran rotella 10w30, it was $12.99 a jug at tractor supply. Ran her for about 2 hours that day and a hour yesterday, the oil was so clean today, after 3 hours of running, i couldnt see it on the dipstick.