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Short Plug

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NolinKerry

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I have a 1950's Evinrude 25HP outboard, serial # 25916. Runs fine, I rebuilt the carb and ignition a few years back but the spark plugs a just a bit too long for the engine cover. I currently use Champion J4Cs.
Is there such a thing as a conversion chart that shows similar performance to these but in a shorter version?
Am I splitting atoms and any short plug will do??
 
racerone said:
Calls for J8C----But did you change plug boots / plug wires?
Click to expand...
Yes, I went by an old shop manual when I purchased the J4Cs, I also changed to newer plug wires. The boots or plugs or both are too long to put the cover back on. It is a sunny day crappy boat but I'll be fishing more this Fall and wanted to get it more weather proof...
I don't think the original wires had boots??
I think I'm going to go ahead and try to find old school wires/connectors, change the plugs, pull the flywheel again and replace all the above, I was kind of looking for an easy solution.
 
Does it have the little cover for plug access on the back?----I would modify that to work with your plug wire upgrade.
 
Your serial number indicates it is a 1954 model that does not have the rear access to the spark plugs. Yours is the hinged two piece design. Just change the spark plug boots to the original sized version.
 
This is the greatest forum. Nerds, everyone of you. Now I'm visualizing this thing repainted.
If I replace the wires any issues with wire gauge/design I should be aware of?
Recommended website? My model, 25916 does not show a parts listing here. Is there a "close enough" model/serial number I can use.
 
NolinKerry said:
This is the greatest forum. Nerds, everyone of you. Now I'm visualizing this thing repainted.
If I replace the wires any issues with wire gauge/design I should be aware of?
Recommended website? My model, 25916 does not show a parts listing here. Is there a "close enough" model/serial number I can use.
Click to expand...
Use 7mm Copper core sparkplug wires with 90º boots. Most auto parts stores should have some, Call ahead.
 
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