Plug & Gap for 650 merc thunderbolt

[bucksaw]

Have a 1969 Merc 650 thunderbolt,it now has champion plugs. Would N.G.K. maybe be better and at what gap. Thanks guys for any info. Oh ya forgot it's a 65 hp.

 

[rickdb1boat]

Re: Plug & Gap for 650 merc thunderbolt

1969 MERCURY 650S 65.0 hp<br /><br />Spark Plug Part No. Stock No. Plug Gap --- <br />Standard BUHW # 2622 <br /><br />This is a Surface Gap Plug that NGK recommends. You may want to check with a Dealer or Repair shop to see if that has been changed! What are you running now?

 

[rickdb1boat]

Re: Plug & Gap for 650 merc thunderbolt

Should be L76V or L77V Champions! Surface Gap!