2010 150 optimax spark plug gap size

[nitro 90]

Looking for gap size for 150 optimax motor, I'm replacing my spark plugs. Thanks

[remaly181]

Courtesy of Don Weed

http://www.bbcboards.net/mercury-3-l...ed-3-15-a.html
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Spark Plugs:
-QL77CC (Champion) for 3 Liter EFI's (XB models or 2001 and EARLIER: .035" / All 2002-> Down-draft intake models: .040")
-IZFR5G (NGK)@ .032-.033" for Standard Opti's 135-225HP, 2001 200XS, and 200 ProXS PRIOR TO Serial Number#1B912786***
-IZFR5J (NGK) @.032-.033 for 75-115 Opti's
-IZFR6J (NGK)for 150/175/200 ProXS (200 ProXS Serial #1B912786-up) & 225-250 ProXS and Racing XS Motors
-2006 & prior ProXS: .032-.033"
-2007 & up: .042-.044" gap for best idle performance. (150/175/225/250 ProXS/XS)
- 2007 & up 225-250 XS/ProXS can use NGK- IZFR6J (gapped to .042-.044") OR IZFR6J-11 (pre-gapped, currently a "factory only" plug)
-2007 & up 225 ProXS: .042-.044" (IZFR6J)
-175 ProXS: .042-.044" (IZFR6J)
*** 200 ProXS Models manufactured PRIOR TO 2/1/12 utilize IZFR5G(NGK) Plugs.
*** 200 ProXS Models manufactured AFTER 2/1/12 (Serial Number 1B912786 and later) will utilize NGK- IZFR6J (gapped at .042-.044") due to production changes in the engines.

-IZFR7M (NGK) for 300XS: .044" Gap

[nitro 90]

Wow, thanks for the info

[jsethook]

Can you not buy plugs with the gap already set?

[rocketman6965]

Very difficult to find. They have extra suffix number (see "remaly181" post) where the 250 ProXS has a pre gapped version IZFR6J-11. Most people, even SOME Mercury techs, think they are properly gapped out of the box. Not so.

Can you not buy plugs with the gap already set?