65 hp merc thunderbolt plugs

[bucksaw]

Just picked up a 1969 65 hp merc thunderbolt 4 cylinder 2 stroke. It now has champion surface plugs # QL76V Now would it be a good Idea to go with something else or not. And if anyone knows of a better plug maybe I could get the number. Thanks for any info!

 

[vinney]

Re: 65 hp merc thunderbolt plugs

THATS THE BEST PLUG FOR THAT OLD MERCURY. THOSE ARE THE BEST ENGINES EVER MADE. AS LONG AS THE IGNITION IS IN GOOD SHAPE THAT PLUG WORKS WELL.SWITCH BOXES GO OUT ON THEM. V

 

[Rex]

Re: 65 hp merc thunderbolt plugs

My book say a champion j4j.<br />Some of those enginge were set 5 degree slow<br />on high end timing. It in the boot.<br />look for topic 5 degrees slow and it will<br />tell you the book # and the page to find it on.<br />Rex a.

 

[bucksaw]

Re: 65 hp merc thunderbolt plugs

Thanks for the Info guys!!!

 

[12Footer]

Re: 65 hp merc thunderbolt plugs

Regardless of what plug you use, it is vitally important to stay in the same heat range.Hotter/colder plugs WILL damage the engine.

 

[rickdb1boat]

Re: 65 hp merc thunderbolt plugs

I had a 1967 65HP. Used QL76V with no problems. They are the correct plug! Stay with them!

 

[bucksaw]

Re: 65 hp merc thunderbolt plugs

Again thanks for the Info on the plugs guys.