- "Klein's Korner"
- What's being said...
- And if you are still not convinced…
- The Optimal Motor Oil for the Vintage Engine: API SM vs. Classic Car Motor Oil
- The Optimal Motor Oil for the Vintage Engine- Part II
"Klein's Korner"by John Klein, Director
As you probably noted in the last issue of the Beeper, we have launched our Classic Car Motor Oil project. Classic Car Motor Oil is now approved as a Regional Project, by the National Classic Car Club of America. Helen Vogel and Gene Perkins introduced it at the Annual Meeting this month in Seattle, Washington. An article and advertisement is forthcoming in the National Bulletin. This oil is really the best one for a Full Classic. If one bought it for no other reason, the preservatives to keep oil on bare metal would be enough. Our cars do a lot of sitting and relatively little driving. Most often this prostrate state includes a variation in temperature and humidity. As you may know, my other big hobby is aviation. The largest killer of private aircraft piston engines is lack of use (less than every week) and as a consequence the resulting fine rusting that abrades all surfaces associated with motion.
The primary concern with modern oil (now API category SM) in the old car literature and various anecdotal reports is reduced levels of ZDDP (zinc dialkyldithiophosphate). ZDDP is an alkyl ZDP (zinc dithiophosphate), initially used as a bearing corrosion inhibitor, is the most long lived (degrades or is used up in the longest length of time) of the ZDP class of compounds. Later, ZDP's were used as "anti-wear agents for highly loaded rubbing surfaces", according to Gibson in his paper, "Fuels & Lubricants for Internal Combustion Engines-An Historical Perspective". ZDP use apparently begin in the 1940's. Olree and McMillan in their 2004 Society of Automotive Engineers paper, "How Much ZDP is Enough", said that the ILSAC/OIL Committee recommended about 930 PPM (parts per million) ZDP to protect modern engines and the preponderance of the older gasoline-powered passenger car and light duty trucks that are left on the road from engine wear. The ZDP seems to be most important as an anti-scuff agent in the break-in period. Olree and McMillan concluded, "This paper does not conclusively answer the question posed in the title, nor does it answer all the questions about wear mechanisms that govern current and post wear facts. What it does suggest that 0.08% phosphorus (about 1000 PPM zinc in ZDDP) in the form of ZDP, is more than adequate to protect both current and older engines from scuffing and wear." Zinc concentrations in oil decrease with use. Twenty years ago the decrease was 50% or more but in modern oils it is much less.
Classic Car Motor Oil has 1600 PPM of ZDDP, which the chemist at DA Lubricant Company feels is correct. The current API-SM oil has 600-800 PPM ZDDP but the goal is to continue to decrease the concentration.
In addition, the use of high quality viscosity modifiers in Classic Car Motor Oil are designed to degrade less with time and temperature and thus allay friction and wear—another good reason to use our oil.
I picked up two cases of Classic Car Motor Oil from DA Lubricant and have placed ten quarts in the 1937 Packard Twelve I am restoring. It runs great with that oil.Buy some!
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What's being said...
Recently a special oil product for older design or antique automobile engines has become available.
This product "Classic Car Motor Oil" was formulated basically to provide the correct amount of zinc (ZDDP 1600 PPM) to protect valve train components. In addition, high grade viscosity modifiers which do not degrade sighificantly with time and temperature, were included.
The effect of these high grade viscosity modifiers has been demonstrated to me in my 1941 Lincoln Continental V-12. Before using CCMO, my oil pressure would drop at highway speeds until it really became a concern. Now, the oil pressure stays in mid-range, and I know that my cam shaft and lifters are protected.
I highly recommend the use of Classic Car Motor Oil in your antique, classic, or special interest automobile.
Hugh P. McKnight
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From the February 2010 Turning Wheels
Studebaker Drivers Club, "The Co-Operator", edited by Bob Palma.
And if you are still not convinced…
…about the need for adequate ZDDP (zinc diakyl dithiophosphate) in your engine’s motor oil if you have a flat-tappet camshaft valve train, we herewith offer this documentation from High-Performance Advisor Jim Pepper. Jim included the following comments with the photographs.
Here is some recent, dramatic, evidence about what may happen when motor oil with inadequate ZDDP is used in engines with flat-tappet valve trains.
These photographs were taken in mid-October 2009. They are of a new, name-brand, competition camshaft and lifters from a friend’s 429/460 Ford. These parts have only about 20 minutes of proper run-in time. All but 4 lifters were severely wiped off, as you can see, as were the camshaft lobes.
The only mistake was that the wrong oil was used.
The engine is now apart and needs a complete rebuild due to metal having fouled the oiling system. All the bearings are scratched, as are the crankshaft journals. In fact, the photos do not do justice to the damage done to this engine.
As I said earlier, my opinion about the ZDDP concentration needed for our collector-car engines is based on factual evidence such as this.
We certainly thank Jim for his report with these dramatic photos. Neither Jim nor I are aware of any Studebakers having been manufactured without the very same flat-tappet valve train setup illustrated in these photographs, a valve train that simply must have a higher concentration of ZDDP than is found in contemporary motor oil of any brand, if that oil is marketed for late-model vehicles.
Here is an interesting e-mail from John Clary in Greer, South Carolina. This came over the transom before Jim’s report and photos.
I have been following your information on ZDDP in The Co-Operator. I have been in SDC since 1975 and for many years, hardly missed any local meets, but have made it to only four nationals. For the last several years, our family has had some illnesses and members passing, so I had to put my car hobby on the back burner for a while. When I read the article about ZDDP, I almost became afraid to drive my Studebakers! Our local car parts dealers merely gave me a blank stare when I mentioned the change in oil additives.
I have a good friend who is an excellent mechanic. He is also a fleet manager for a major truck leasing company, managing a fleet of large diesel trucks. He also has a 1957 Ford that would be the envy of any old southern bootlegger. I made a copy of your article (with the recent amount correction) and gave it to him. He said that this was the first he had heard of the situation!
He buys Valvoline in bulk and called and talked to a Valvoline technical engineer. For the SAE 30 HD oil we use in many of our collector cars, the Tech guy told my friend that Valvoline VR1 Racing Oil has the correct amount of ZDDP and appropriate detergents for our engines.
I went to my local parts store and bought the 5 quarts they had. The owner said he would get more and keep it in stock. I prefer to use off-the-shelf oil, rather than buying cans of additive and hoping to get the correct mixture. Also, if a car needs the oil topped off, it would avoid the question of how much additive should be added if you were using oil containing insufficient ZDDP. This Valvoline product, and other oils you’ve mentioned, would take care of this problem.
The reason I am sending you this is because some people have said they are tired of hearing about it. I didn’t want to pester everybody with a subject that everyone is tired of. However, I don’t think we can over-stress the importance of something so important to keeping our engines running.
- John Clary
Thanks for your input. Yes, I understand Valvoline VR1 Racing Oil does have enough ZDDP in it, and I agree with your findings. In fact, I believe that is the very oil Jim Pepper personally uses. Also, I have some Valvoline technical data here to that effect. (According to their website, they also market a “Not Street Legal” Specialty Racing Oil with 1% more zinc and 1% more phosphorus than VR1 Racing Oil.)
I’m surprised your fleet manager friend had not heard of this ZDDP issue. In reality, “the problem” has been going around collector-car circles about four years now. I guess his company doesn’t have any old flat-tappet cam engines for which they need the higher level of ZDDP. (If your friend’s 1957 Ford has an original, flat-tappet Y-block V-8 in it, he’d better be running a ZDDP-enhanced oil or using an additive, or he’ll wipe the lobes off that camshaft in due time…especially if it’s a 300 hp supercharged 312; “the envy of any old southern bootlegger,” as you say!)
You are right, John; some people are tired of this being discussed. However, I am keeping a file of information such as yours and will be running periodic updates in The Co-Operator every six months, whether people like it or not! It’s important to keep the right oil in our engines, things are changing all the time, and this applies to virtually every Studebaker vehicle except those that are horse-drawn, or have late-model, “other-brand” engine swaps that may employ roller-lifter-camshaft valve trains. Thanks again for your note, John.
This topic was discussed at length in the September 2009 Co-Operator, so we will not dwell on it again so soon. Readers seeking more information are directed to that issue of Turning Wheels.
Valvoline Racing oil is not designed for long term use it is for short intense use and racing purposes. Classic Car Motor Oil is designed for long term use in vintage engines and is the optimal oil.
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From Issue #2 March - April 2011 issue of Indiana Region Classic Car Club of Indiana
The Optimal Motor Oil for the Vintage Engine: API SM vs. Classic Car Motor OilBy Dr. John Klein
Motor Oil provides several functions besides lubrication. Normal engine wear is caused by contact between moving surfaces and corrosive wear of metal surfaces. Two engine design factors that limit such wear are separation of metal parts by a lubricant film and protection of metal surfaces with chemical coatings. Motor oil separates, cools, and cleans metal parts, reduces friction, and controls rust and corrosion.
Motor oil is made by mixing base oil (mineral or synthetic or a combination) with chemical additives. These additives include viscosity modifiers, cold flow improvers, detergents, dispersants, rust and corrosion inhibitors, anti-wear agents, oxidation inhibitors, and antifoam agents. The resulting motor oil is a carefully balanced package and should have no after market additive to modify it.
The current motor oil is American Petroleum Institute (API) classification category SM. This came out in late 2004. The API oil classification system was set up as a joint effort by the American Society for Testing and Materials (ASTM), API, and the Society of Automotive Engineers (SAE). API-SM was designed by the ILSAC/Oil Committee made up of a group of people from OEM’S, oil additive companies, and oil companies. This group decided that for the next few years (until ILSAC GF-5 about 2010) the maximum phosphorus level would be 800 ppm (about 870 ppm zinc dialkyl dithiophosphate [ZDDP]). There is no minimum level.
ZDDP is the most prominent ZDP (zinc dithiophosphate) used in motor oil. ZDP use in motor oil began in the 1940’s as a bearing corrosion inhibitor. Later ZDP’s were used as “antiwear agents for highly loaded rubbing surfaces”, according to Gibson in his paper, “Fuel and Lubricants for Internal Combustion Engines-An Historical Perspective”.1 The camshaft -lifter interface is the most prominent and critical area where these “highly loaded rubbing surfaces” are manifest in the internal combustion engine. No one knows for sure how ZDP’s decrease wear. They do coat the rubbing surfaces and are sacrificial. ZDDP is the most used and well known of the ZDP’s. It has antioxidant and corrosion inhibiting properties. ZDDP is an excellent additive, relatively inexpensive, and well entrenched in the automotive motor oil industry. The quantity was first regulated in 1992 with ILSAC GF-1 allowing a maximum of 1200 ppm phosphorus (about 1300 ppm ZDDP). Prior to this, phosphorus had been to at least 1500 ppm (about 1650 ppm ZDDP). McMillar and Olree in their paper, “How Much ZDP is Enough?”2 in 2004 said for the next few years the phosphorus level should be 750 ppm “…to protect modern engines and the preponderance of older gasoline-powered passenger car and light duty trucks that are left on the road from engine wear”. In the same article relative to a 1963 SOHC 6-cylinder Kaiser Jeep Tornado engine it was stated, “We believe that a much better path to follow would be to determine what minimum phosphorous level, if any, is needed to protect modern engines.” The conclusion was that a phosphorus level of 800 ppm (about 870 ppm ZDDP) in the form of ZDP “… is more than adequate to protect both current and older engines from scuffing and wear.” The article also states, “This is far less than the 0.10% [1000 ppm-1090 ppm ZDDP] phosphorus level that some have extrapolated, from old tests and old oil formulations, to today as necessary to protect today’s vehicle fleet.” It is expected that ILSAC GF-5 about 2010 will have 500 ppm phosphorus [545 ppm ZDDP].
Even if one does not believe the reports from multiple sources attributing the rash of camshaft and lifter wear in the last three to four years or so to API SM oil, one must be concerned about the continued diminution of ZDDP in the future oils. There are thousands of collector engines with flat tappets. The majority of these has been or will be rebuilt with ground camshafts or new aftermarket parts of widely varying metal quality. A level of at least 900-1100 ppm ZDP of the right mix (alkyl, aryl, short, medium, and long chains) can provide some measure of safety.
The continued removal of phosphorus from motor oil is to increase catalytic converter life. The phosphorus in burned motor oil can coat the active substrate in the converter.
Multiple viscosity engine oils came into use in the 1950’s. Prior to that mono-grades or straight weights were in use. I remember that when I first became interested in cars in the mid-50’s, the norm in Indianapolis wasSAE 20 in the winter and SAE 30 in the summer. This was the convention I followed with my 1949 Ford V-8. Oil technology has improved and we have a better product available than the straight weight nondetergent oils recommended sixty or more years ago. With rare exceptions, the multigrade oils perform better in gasoline engines than mono-grades. At start-up with a cold engine the thinner, less viscous multigrade oil is pumped more readily by the oil pump to the wear points. Start-up is a high wear time. There is less strain on the oil pump and its drive gears. The multi-grade motor oil thins less with temperature and at 212 degrees F (100 degrees C) a multigrade such as SAE15W40 is the same viscosity and provides the same oil film thickness as a mono-grade. In this case each would be a viscosity of SAE40 at 212 degrees F. Beyond 212 degrees F a multi-grade retains its viscosity and oil film thickness better than a mono-grade which will drop in viscosity more with temperature. The multi-grade adds a measure of protection in the high temperatures at the piston ring-cylinder wall interface. The thicker multi-weight does not get thrown into the cylinder as easily and thus decrease oil consumption and deposits on pistons and combustion chambers.
High quality shear stable viscosity modifiers are necessary to retain optimal viscosity and oil film thickness. Viscosity modifiers are oil soluble polymers which reduce oil viscosity loss with increasing temperature. Shear instability may be temporary or permanent. Temporary shear is deformation of the polymer under load causing a functional loss of viscosity and oil film thickness protection. Back in the oil pan under no load the viscosity is normal. Permanent shear is a breakage of the polymer. API-SM polymers are designed to shear more in a temporary than a permanent basis. The purpose of this shear instability is to create less engine drag and increase fleet miles per gallon to help meet C.A.F.E. standards. The lower SAE number and shear instability are feasible in new engines because of tight tolerances of very smooth opposing moving surfaces. API-SM motor oil is designed for new automobiles with roller camshaft followers, tight smooth tolerances, specifically designed know metallurgy, catalytic converters, and an automobile company’s desire to meet C.A.F.E. standards. API-SM is a fine motor oil for its design use in new vehicles. It is not the optimal oil for collector vehicles. These vehicles most often have flat tappets, more loose and relatively rough clearances, metal of varying quality and treatment, no catalytic converter, and no need to meet fleet C.A.F.E. standards.
The optimal oil for vintage engines is absolutely Classic Car Motor Oil (CCMO). This oil was formulated by DA Lubricant Co. in Indianapolis and is manufactured exclusively for the Indiana Region Classic Car Club of America since December, 2007. The oil is a project of the Indiana Region sanctioned by the National Classis Car Club of America. DA is a high quality company established in 1919 with a legacy of motor car racing. Their forte is designing oils and greases to solve industrial problems. Classic Car Motor Oil has a strong detergent and dispersant package to keep the vintage engine clean. It may be used with or without an oil filter. We don’t recommend CCMO if your engine has been using non-detergent oil- not many engines today. The presence of a preservative package that meets military specification number MIL-PRF-21260E is enough reason alone to use Classic Car Motor Oil. This package was designed to prevent rusting of bare metal engine parts while the engines were shipped overseas by boat in World War II. These engines had to arrive ready to use and not be rusted. The rusting in engines shortens life by degradation of the corrosion itself and by the production of fine rust particles that abrade all surfaces associated with motion. Collector cars do a lot of sitting in all conditions of storage and relatively little driving. The lack of use coupled with non-optimal storage mimic the number one killer of private piston airplane engines-rust. Classic Car Motor Oil is readily available, reasonably priced, and far and away the best oil for the vintage engine. The functional gap between Classic Car Motor Oil and API classification oils will only increase in the future.
Use Classic Car Motor Oil.
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From Issue #2 March - April 2011 issue of Indiana Region Classic Car Club of Indiana
The Optimal Motor Oil for the Vintage Engine- Part IIBy Dr. John Klein
This will serve as an addendum to my article, “The Optimal Motor Oil for the Vintage Engine: APISM vs. Classic Car Motor Oil.” GF-5 was promulgated effective 1 October, 2010 by the ILSAC/Oil Committee. The new motor oil for modern cars is API-SN, which supercedes the previous standard, API-SM. SN permits the same average cam wear on modern engines as the older SM. The maximum phosphorus content remains the same at 0.08%, but with the new stipulation that the oil must retain 79% of its original phosphorus content with use. The stated purpose of this rule is to extend catalytic converter life. This change has been facilitated by changing the ZDDP molecule so that it is less volatile while retaining the same or better function. The major anti-wear agent in SN is ZDP compounds.
The following is a statement by Conoco-Phillips explaining the benefits of GF-S (SN) oils over the previous generation GF-4(SM) type. “In summary, the ILSAC GF-5 standard provides enhanced performance benefits compared with the GF-4 standard. The improvements include better protection against high temperature deposits, better protection against engine sludge and varnish formations, improved protection of emission system catalysts, and fuel economy improvement. Also new tests have been included to insure compatibility with E85 fuel, compatibility with various elastomer seals, and protection of turbochargers.” As you can see from this statement and the information that preceded it, SN motor oil is good for modern engines but offers no improvement over SM for vintage engines. The emphasis with SN is on fuel economy and emissions control.
Classic Car Motor Oil is designed for the vintage engine. The emphasis is on engine protection and longevity. The viscosity index of our high quality viscosity modifiers is 24 vs. 50 for SN. This means that CCMO is twice as sheer stable (retains viscosity and oil film thickness in static and dynamic conditions) as SN oil. This better viscosity retention cushions and protects vintage engines with their less refined metallurgy, larger and less smooth tolerances, and flat tappets rather than roller camshaft lobe followers.
In summary ,despite recent changes in oil specifications, Classic Car Motor Oil remains the optimal oil for the vintage engine. Trusting your investment to SN oil with or without ZDDP concentrate added in the field simply doesn’t make sense. Viscosity retention, an optimal level of ZDDP, and strong anti-rust protection are all persuasive reasons to use CCMO instead. Classic Car Motor Oil is a well balanced package designed to be the optimal for vintage engines. Leave the SN for your modern drivers.
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