First UOA on this car. It's a new (to me) '94 Miata with a FM II turbo. The car has 140K miles on it, but the motor has been apart at least once, and supposedly not that long ago. The oil is Red Line 10w40 with 7,500 miles which is a lot longer than I'd normally run it.
Talked to Blackstone and they were concerned about wear metals, specifically copper which seems high to me but not way out of line for 7500 mile oil. Iron, lead, and aluminum are high too.
Quoth Blackstone: "Lead and copper show bearing wear and iron is from steel parts, probably a rotating shaft, but could be cylinders walls too since aluminum from pistons and chrome from rings are high too. This engine does have a turbo installed, so that might leave a little more metal behind than stock, but probably not this much. Fuel at a trace level isn't harmful. The TBN is 5.0 showing active additive, but drop to 2,000-3,000 miles on the oil since wear is high."
I'm debating whether to tear into the motor this winter since I'll have it out anyway, or to drop it as-is into the Exocet we're building. Before we pull it we'll take compression and put a mechanical oil pressure gauge on it to get accurate oil pressure.
Opinions, analysis, wild speculation, and free beer are always appreciated.
Code:
ALUMINUM 6 Univ Avg 3
CHROMIUM 5 1
IRON 54 10
COPPER 10 4
LEAD 53 3
TIN 2 1
MOLYBDENUM 208 91
NICKEL 1 0
MANGANESE 1 1
SILVER 0 0
TITANIUM 0 0
POTASSIUM 6 1
BORON 66 61
SILICON 15 11
SODIUM 12 37
CALCIUM 2491 2218
MAGNESIUM 139 192
PHOSPHORUS 1010 790
ZINC 1153 918
BARIUM 0 0
SUS Viscosity @ 210°F 67.3
cSt Viscosity @ 100°C 12.24
Flashpoint in °F 370
Fuel % TR
Antifreeze % 0
Water % 0
Insolubles % .4
TBN 5
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