99 Mercury 225 EFI spark plugs.
Serial # OG937865
I am running NGK BR8HIX
Manual states NGK-BU8H
I have done some internet searches and found alot of people saying Champion QL77CC for this motor.
The NGK BR8HIX that i have been running for 5 years i have owned the boat have been flawless. Never a problem and runs like a champ which makes me lean towards keeping them.
Just wondering what Don recommends and why i keep hearing to run the Champions
CHAMPION: QL77CC IS THE ONLY FACTORY-RECOMMENDED PLUG (and was designed SPECIFICALLY for these 3L EFI engine models).
BU8H was never recommended for this 3L engine (you may be refercing a 2.5L manual).
Last edited by EuropeanAM; 05-07-2013 at 04:15 AM.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
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Some can only run the Champions due to electronic interference with the ECU's. They are not what the factory recommends, but plug technology has come a long way since that motor and manual were developed originally. If you can run the Iridiums (appears you already are by the part number you posted), keep using them. All I run. My original set ran for 4 seasons, showed little sign of wear and ran great, but I replaced them this year. Gman
"Better to remain silent and be thought a fool than to speak out and remove all doubt."
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