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Spark Plug Wires Confusion

K

Klink

Regular Contributor
I need a spark plug wire for a 1993 25hp Johnson Electric start. I look on MarineEngines.com (ME) and they show the OEM wire (which I assume is solid core stainless steel) which comes disassembled and they show different sizes of assembled wires from Sierra.

I tested the OEM wire I have and it has no continuity. It is an OEM spark plug wire, made with a stainless steel wire. I have some spare blue Sierra spark plug wires from another engine, and they are made of some non-metalic fiber that does not show continuity with a multimeter. I assume that these blue wires are the same as the blue offered by ME.

My question is how do you test those blue wires for resistance? How do I know they are good? Why would I need to switch from solid stainless steel core OEM wire to Sierra's blue fiber cord? I had some spare OEM wires that showed 2 ohms resistance and threw them away, as the manual said they should have zero resistance. Now if I understand correctly these new Sierra blue wires have resistance way above 2 ohms, and they are OK? I'm baffled.
 
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You threw away some good wires, 2 ohms is practically no resistance. I wouldn't run the non-metallic wires. You can buy solid core wire by the foot at any marine dealer, along with the ends. Or just re-use the wire ends you already have.

Better yet, go to a small engine repair shop and get their wire.. anything that says "boat" is twice as much money for the same stuff :)
 
bill_w said:
You threw away some good wires, 2 ohms is practically no resistance.
Click to expand...

Ran to the corner and picked through the garbage and found the three old wires. I retested them, they are just wires no ends now, and they actually tested at 0.1, 0.3, 0.6 ohms. I'm in the process of rigging one up with the ends. Thanks

P.S.- the spring terminals on the bad wire that had no continuity looked like as if they were stainless steel, they look brand new. The spring terminals on the spare wires had corrosion on them. I though they were all stainless steel but they are not, they are magnetic. Like I said; the spring terminals on the bad wire that had no continuity looked as if they were stainless steel. They look brand new, and I attribute it to a thick coating they had of some white pasty grease. Is there some grease that is used on the spring terminals to protect them from corrosion? The manual says to coat the spark plug ceramic with grease but never have I heard of covering the spring terminal with anything.
 
Glad you saved the wires :) I've used grease on the ends of the spark plugs to stop corrosion, never had it mess up the continuity. I'd try checking the stainless parts themselves for continuity, just out of curiosity. Good luck with the motor.
 
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