Home › Forum › Ask A Member › Oliver Bendix Coils › Reply To: Oliver Bendix Coils
Just a side note about using “unknown quality” black rubber for high voltage insulation. I had used a couple of pieces of black rubber tubing as gromets and found after much aggravation that the rubber was conductive and shorting the spark. Apparently enough carbon black in the rubber compound was the culprit. Check resistance on high ohm scale before use. I had written a tech article for the “Outboarder” about this , several years ago.
Joe B
That’s for sure the truth! A few years ago at Tomahawk I was observing efforts to get a Johnson outboard running. It was one of the low tension mags and as such was fitted with a pair of Sierra branded coils which came with spark plug wires attached….along with “rubber” spark plug boots. An observant on-looked noticed big fat sparks jumping from the “rubber” boot to the block. No wonder the engine was missing. We removed the “rubber” boot…..problem solved.
Not all rubber has the same insulative properties…..and you can’t tell by looking at it.
I don’t know if Sierra ever acknowledged the issue with their “rubber” boots.