DETERGENT OIL vs NON DETERGENT

[Jon-Ohio]

It is getting hard to find 40 wt non detergent oil anymore. MY 1930 engine is stock rebuilt with no add on oil filter.

Are detergent oils -OK - ie Shell Rotella ? - or something else ?

Thanks for any advice and help

Jon in Ohio

[Ernie Vitucci]

Good Evening...If your engine has just been rebuilt, then you can run detergent oil with no problem. If you have over 1000 miles on the engine, then you should drop the pan and clean it out first and maybe remove the valve cover on the right side of the engine and do the same..Others might come along with a different take. Ernie in Arizona

[Peyton]

It’s getting hard to find conventional oil now. Synthetic oil is becoming competitive in price with conventional oil and many seem to be using it. Synthetic oil is said to hold up better under hotter temps. Looks like I’ll be using it too.

[CWPASADENA]

[QUOTE If your engine has just been rebuilt, then you can run detergent oil with no problem. If you have over 1000 miles on the engine, then you should drop the pan and clean it out first and maybe remove the valve cover on the right side of the engine and do the same. QUOTE]

I doubt if at 1000 miles, there would be much buildup of sludge when using non detergent oil and changing to a detergent oil would not be a problem.

My opinion,

Chris W.

[Certimafied]

I think any oil today would be better than what the engine had new. Rotella has more vitamins and minerals in it I use it in some older engines because of that. Cheaper the VR1 oil too.

Ive heard to steer clear of detergent oils in old used engines because of the risk of knocking some nasty gunk loose that may clog up an oil passage and cause damage. Ive used both in old straight 6 chevy truck engines without oil filtration, it did seem like the detergent oil got nasty much quicker than the non detergent, sometime the oil got chunky too. But these were pretty worn out and used hard engines. Cant say what that did to hurt or improve longevity, I never held on to the trucks long!

I did have one I drove daily for about 2 years, it burned oil so bad in two cylinders. They would foul and start misfiring in traffic lights longer than 1 minute, with antifoulers installed. Any how I was told and learned that synthetic oil smokes less than conventional oil. The plugs still fouled but at least everyone could kind of see once I left the light.

[David R.]

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Look in Farm Supply stores for non detergent oil.

[Ray64]

Most all dollar stores and the like carry it

[WHN]

What OIL to use? That’s a question I’ve never heard before!

My experience. Even on high mileage engines is to switch to High Detergent. I have always dripped the oil pan on older engines first. Sometimes there is a lot of sludge, sometimes there is very little.

I mainly have used 20w-50 HD. If the engine has a lot of mileage, I add one bottle of blue STP as the last half quart.

I have been using high detergent oil for over 30 years now in our Model A’s. Before that, only non detergent oil. The high detergent oil works much better.

I would stay away from synthetic. Owners have mentioned problems with gaskets leaking.

Enjoy your car.

[jack backer]

The difference between synthetic and conventional oil is molecular, the molecules of convention oil are random sized, in synthetic they are consistent in size.. this provides for a more ‘stable’ oil, and allows for better ‘chaining’, the attaching of additives to the oil to improve oil performance. Diesel oils have a high load and shear additive, good for the A’s babbit bearings and wide piston rings.

[BRENT in 10-uh-C]

Originally Posted by WHN

What OIL to use? That’s a question I’ve never heard before!

.................................

Originally Posted by WHN

I would stay away from synthetic. Owners have mentioned problems with gaskets leaking.

I feel dried cork gaskets, -or deteriorated paper gaskets are going to leak no matter what type oil is used. Correct the gasket issue and then use synthetic oil. As an engine rebuilder, it is my opinion the benefits of using synthetic far outweigh using organic oils in a Model-A engine. Maybe in a Model-T engine, not so much.

On the other hand, if you want to discuss controversial oil thoughts, let's discuss the benefits of using Lucas, Slick-50, Marvel Mystery and other oil additives!

[Ruth]

Originally Posted by BRENT in 10-uh-C

.................................

On the other hand, if you want to discuss controversial oil thoughts, let's discuss the benefits of using Lucas, Slick-50, Marvel Mystery and other oil additives!

Please do, and let's not forget STP.

[fried okra]

A lot of folks seem to be running a dash of Marvel Mystery "oil" in their fuel.

Any thoughts on that

[Terry, NJ]

OK! This is what I do! Not saying it's right, but it's what I do! Non det. oil's getting scarcer and scarcer, Why is that? Because there's better things! I bought an old A engine once. I took it apart only to find out it was a clogged up with all kinds of smut. The oil screen was about 80%. Since the A eng. depends on flow, not pressure, it was getting neither. Solution, Run Detergent oil! That was real easy! From what I know, you could probably run cooking oil in the crankcase. If it oil and it pours, it'll be OK! Remember, The best oils of 1930 are NOT as good as the worst oils of today!
Terry

[Jim Brierley]

Originally Posted by Terry, NJ

OK! This is what I do! Not saying it's right, but it's what I do! Non det. oil's getting scarcer and scarcer, Why is that? Because there's better things! I bought an old A engine once. I took it apart only to find out it was a clogged up with all kinds of smut. The oil screen was about 80%. Since the A eng. depends on flow, not pressure, it was getting neither. Solution, Run Detergent oil! That was real easy! From what I know, you could probably run cooking oil in the crankcase. If it oil and it pours, it'll be OK! Remember, The best oils of 1930 are NOT as good as the worst oils of today!
Terry

AMEN!!! Why would anyone not use modern oils, they are much improved compared to old oils. No additives are needed.

[WHN]

Originally Posted by fried okra

A lot of folks seem to be running a dash of Marvel Mystery "oil" in their fuel.

Any thoughts on that

I have been using Marvel Mystery Oil for years. Seems to help with sticking and/or noisy valves.

Enjoy.

[rotorwrench]

Non-detergent oil is only good for break in on a short schedule. Detergent oil should be used after break in. If an engine has set for a long time or is in uknown condition, the pan should be pulled for cleaning and bottom end inspection before operating it for any length of time. Dumping the oil is the only way to get rid of contaminants and detergent oil holds stuff in suspension so it can be drained out.

Oil is cheaper than engine overhaul. Any oil is better than none. 10/30 or higher vis if you want. It won't be in there very long with no filtration anyway.

[fried okra]

WHN....you use Marvel in the fuel tank, or the crankcase maybe?

[Herb Concord Ca]

Ditto on #15 reply, I use Marvel Mystery Oil in gas at every fill up. Especially with the corn gas we have today.

[jack backer]

Marvel oil is a light distillate with a heavy solvent content,akin to automatic transmission fluid.if you put enough in your fuel it will provide some upper cylinder lubrication, really not needed in a low compression L head with thick piston rings. Pouring a light oil with solvent in your crankcase is foolish, you need more viscosity not less.. the only mystery is why folks use it..

[WHN]

Originally Posted by fried okra

WHN....you use Marvel in the fuel tank, or the crankcase maybe?

Mixed with the gas.