Newbe and questions.

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Sep 8, 2002
Huntsville, AL
Hey all - New here. I am a working stiff that loves Datsun Roadsters (and my wife and kids:). I have a '66 1600 and building a custom 67.5 with Buick GN turbo 3.8 with WC T5 5 speed. Been lurking a while have read a lot of this forum and find it very good! I have been working in Tribology for 13 years, but don't call myself a "Tribologist" because I don't have the paper on the wall. Mine says Materials Engineer. I work mainly in space lubricants and a lot with Solid Film Lubricants. We do get into typical lubes - like now with the crawler transporter bearing issue. On the side we do some motor oil tests with the Shell 4 ball tester. Over the years we have tested many oils. We have tested new and used oils at various miles in many cars. As you can guess, synthetics are always on top. I run Mobil 1 in my cars now. A rep for Royal Purple came by the other day and dropped off a bunch of oil products and literature. Which (finally) brings me to a question. The RP 5w-30 ran better on the Shell 4 ball then comparable Mobil 1. I read the thread on RP oils and will try some in the Mazda P5. Is anyone familiar with the Shell 4 ball test and how it relates to the real world of motor oils? I feel it tests the EP additives, but this is only part of the picture. Also, I am looking into suggesting to switch all MSFC/NASA vehicles over to sythetics. Do other brands have a complete line of lubes? RP does have a good line of products. RP is a lot of sales pitch, but I work with evidence and not hipe. We have lost satallite performance/big dollars due to engineers believing lube salesmen. As you can guess, we need to test everything until we are blue in the face before we fly it. You all have a great day and keep the good info coming! Phil
Welcome to the board. Its a great place. There is a tremendous amount of knowledge here. Wen I used to work for a living with a Electric Utility, I was interested in converting our generation facility to all synthetis. The two groups which I contacted was Mobil and Exxon who did have complete lines. I am sure you will get responses from the sight sponsors (Mobil, Shaeffers, Amsoil and others.) [Coffee] Again-welcome!!
The Shell 4-Ball wear test and the 4-ball wear test involve 4 steel (52100) balls of 12.7 mm dia. immersed in 10 mL of lubricating fluid. The top ball is placed in a chuck and spun or "ground" into the other three balls (which are clamped or motionless) at various pressures (loads), rpm, and fluid temperature for 60 minutes or longer. The scar or indentations (measured to an acuracy of 0.01 mm) are used to measure the film strength of base and formulated fluids and greases. By using a formula, one can cacluate the coefficient of friction of the fluid or grease in question from the scar (wear)marks. Under a calibrated microscope, the wear scars were measured. Most modern full synthetic fluids show wear scars from 0.48 down to 0.30 mm. It was conceived as a method of forecasting the lubrcants ability to reduce friction. The smaller the wear scar, the lower the coefficient of friction and indirectly the better the film strength. Any lab or bench test only forecasts the fluids ability to show wear results at specific loads, rpms, and temps. Due to the many variables inherent in automotive engine and driver variability, only used oil analysis and trending really show the relationship of the lubricant to the machine. There are three 4-ball wear tests established by the American Society of the Testing of Material (ASTM) for Fluid Lubricants: D5183-95, D2783-88, D4172-94. BTW, D2783, "Standard Test Method for Measurement of Extreme Properties of Lubricating Fluids (Four-Ball Method), has a chart that shows that the load carrying capacity of a fluid that has Antimony dithiocarbamate or phosphordithioate will support 5 X the loads of oils without it and 3 X the loads using ZDDP alone. So Antimony PDT or Antimony DTOC are great extrmeme pressure additives. [ September 10, 2002, 03:04 PM: Message edited by: MolaKule ]
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