[Gary - K7GLD]

Some guys, new to oil analysis, are baffled by some of the terms and numbers seen on their analysis reports - Chromium is high - what does it mean, and where typically (for instance) does Chromium come from in an engine?

Here a decent explanation, lifted from over on BITOG:

I am trying to interpret UOA's. I get info through others comments but like most newbies I don't know alot and get confused by certain elements etc. So Ityped this up for all to print out and have next to them for guidance. To be added/edited as we all see fit.

Mods please move if this is unappropriate for this particular forum.

WEAR METAL SOURCES

IRON……….CYLINDERS, GEARS, RINGS, CRANKSHAFTS, LINERS, BEARINGS, HOUSINGS, RODS, and PLATINGS

CHROMIUM……………..RINGS,ROLLER/TAPER BEARINGS, RODS, PLATINGS

LEAD……….BEARING OVERLAYS, ADDITIVES IN GEAR OIL AND GASOLINE

COPPER…………………BUSHINGS, BEARINGS, THRUST WASHERS, FRICTION PLATES, OIL COOLERS, ADDITIVE IN OIL

TIN………………………………….BEARINGS, BUSHINGS, PISTONS, PLATINGS

ALUMINUM………PISTONS, BEARINGS, PUMPS, BLOWERS, ROTORS, THRUST WASHERS

NICKEL……………………………………………………………………VALVES

SILVER………………………………………….BEARINGS,BUSHINGS,PLATING

MANGANESE……….TRACE ELEMENTS IN LINERS AND RINGS, ADDITIVE IN GASLOLINE.

TITANIUM……………………………………………………….TRACE ELEMENT

VANADIUM……………………………………………………..TRACE ELEMENT



CONTAMIMENTS & SOURCES

SILICON…………………………………….ELEMENT USED TO DETERMINE THE LEVEL OF AIRBORNE DIRT AND ABRASIVES IN THE OIL.(SOMETIMES USED AS AN ANTI-FOAM AGENT)

BORON………………………….PRESENT IN MOST PERMANENT ANTI-FREEZE SYSTEMS AND COOLING SYSTEMS INHIBITORS (SOMETIMES USED AS AN ADDITIVE)

SODIUM………………………………….PRESENT IN MOST PERMANENT ANTI-FREEZE SYSTEMS AND COOLING SYSTEM INHIBITORS (SOMETIMES USED AS AN ADDITIVE)

POTASSIUM………….PRESENT IN MOST PERMANENT ANTI-FREEZE SYSTEMS AND COOLING SYSTEM INHIBITORS (SOMETIMES USED AS AN ADDITIVE IN GEAR OIL)



ADDITIVES AND THEIR FUNCTION

MAGNESIUM……………………….DISPERSENT/DETERGENT ADDITIVE

CALCIUM………………………….. DISPERSENT/DETERGENT ADDITIVE

BARIUM…………………………... DISPERSENT/DETERGENT ADDITIVE.

PHOSPHORUS…………………………...………..….ANTI-WEAR ADDITIVE
.
ZINC…………………………………...…………….…. ANTI-WEAR ADDITIVE

MOLBDENUM………………………...………….…… ANTI-WEAR ADDITIVE


FUEL DILUTION = UNBURNED FUEL IN THE OIL MAY SIGNAL FUEL SYSTEM LEAKS OR INCOMPLETE COMBUSTION.

FUEL SOOT = A RESULT IN INCOMPLETE COMBUSTION OR BLOW-BY. HIGH DRAIN LEVELS AMY INDICATES COMBUSTION PROBLEMS OR OVEREXTENDED DRAIN INTERVALS.


VISCOSITY = THE KINEMATIC VISCOSITY DETERMINED AT 40°C AND/OR 100°C IS A MEASURE OF THE FLOW RATE OF AN OIL IN RELATION TO TIME. THIS DATA IS USED TO ASSIGN AN SAE GRADE TO OIL.


SAE GRADE…………….MIN-cST-100°………………MAX-Cst

10w………………........……4.10………………........………….xx

20w……………………....…..5.60…………….......………….9.29

30w……………………....……9.30…………….....………..…12.49

40w………………….....…….12.50……………..………….…16.29

50w………………....………..16.30…………………...………21.89