O'Donnell 77 standard plug medium

[raytam]

Is the O'Donnell 77 medium glow plug good to use in a 21 with 60%nitro? ambient temp ranges from 60 to 90F. Thanks

Ron

 

[BB Mods's]

To warm for 60% use the blue top or my favorite, the indexed mc-9 like I set you up with.

 

[Rokieboater]

Is the O'Donnell 77 medium glow plug good to use in a 21 with 60%nitro? ambient temp ranges from 60 to 90F. Thanks

Ron

I have used them with no noticeable difference. I do pull the element down. But I do run at an altitude of 5200 feet.

Robert

 

[Will Gallagher]

To warm for 60% use the blue top or my favorite, the indexed mc-9 like I set you up with.

So what is an indexed mc-9??

 

[Terry Keeley]

I've ran them on my 40 hydro, fairly hot plug, should work well on a 21.

 

[Jack ODonnell]

To warm for 60% use the blue top or my favorite, the indexed mc-9 like I set you up with.

So what is an indexed mc-9??

Good question Will

 

[BB Mods's]

mc-9 with 2 loops pulled out.

 

[raytam]

Thanks everyone for the replies.

 

[NAMBA860]

To warm for 60% use the blue top or my favorite, the indexed mc-9 like I set you up with.

HEY TOMMY when you install the plug where do you index it at? 3 oclock 9 oclock or what?

 

[raytam]

namba 860 - what's up with your throttle exhaust venture? I'm kinda interested after seeing this boat go...



BBMods - I tried indexing my other plugs and it burnt out faster. Of course my plug (sh#3) was way too hot for my fuel. Does it matter where you point the wire? Also, I tried your airdam suggestion at it did reduce my boat from wanting to flip but at slow speeds, it tends to go submariner. It happened twice.

 

[BB Mods's]

the index is the height I pull the 2 loops to, not the location of the wire.

that mc-9 should still be alive right Ron?

we need to blueprint that 18 of yours, its got a lot of power left in it.

 

[Will Gallagher]

So what are you tiring to accomplish by “Indexing” your plug? How do you measure this?

 

[BB Mods's]

bring the element out into the exposed bowl of fuel, in theory it improves ignition.