Sparkplugs - 150 Johnson

[dartman]

What sparkplugs work well in these OBs? What is the correct NGK plug?

 

[Dhadley]

Re: Sparkplugs - 150 Johnson

I would definately recommend sticking with the Champions. I use the QL77JC4's in both my 60 degree and the crossflow 150.<br /><br />You can use the NGK's but I would certianly richen up the carbs, especially in the mid range.<br /><br />Good luck!

 

[Mike Langianese]

Re: Sparkplugs - 150 Johnson

Whatever brand you decide to use be sure to use a SUPPRESSOR type plug, (the Q designation on the Champion plug). My repair manuals state that failure to do so MAY cause “erratic ignition system operation”. <br />Mike

 

[AUGIDAWG]

Re: Sparkplugs - 150 Johnson

It will idle a little better with the Champion QL78YC (it has a longer nose), and run just a hair hotter, but not too hot like the QL82YC. The larger the number, the hotter the plug.

 

[Dhadley]

Re: Sparkplugs - 150 Johnson

Which 150 do you have dartman?

 

[ob]

Re: Sparkplugs - 150 Johnson

You never mentioned what 150 hp Johnson you had.These are the Champion plugs recommended by manufacturer.<br /><br />150, 175 (60º V6 Eagle) 1991 & newer QL78YC gap .030 <br />150 Commercial (60º V6 Eagle) 1993 - 2001 QL78YC gap .030 <br />150, 175 Ficht 1997 - 1999 7712 (with non-pinned cylinder heads) .030 <br />150, 175 Ficht 1997 - 1999 XC12PEPB (with pinned cylinder heads) .030 <br />150, 155 (90º crossflow V6) 1978 - 1987 UL77V or L16V Surface Gap N/A <br />150, 175 (90º crossflow V6) 1988 - 1991 QL77JC4 gap .030

 

[dartman]

Re: Sparkplugs - 150 Johnson

Its a 2002 60º V-6 with carbs.