Trojan Boat Forum

Any suggestions on brand for spark plug replacement? Platinum, etc?

I just use whatever I can get nothing special just the right heat range.....
I use Champion XN9Y on my 318's with 35 thou gap

champions are a good plug, just don't go hotter than what's called for if you're runnin' corn-gas you could get a spark-knock

My 78 F30 Express LM318's have RN12YC and I have never questioned it. Should I use a different one? We are on 10% Ethanol here.

I am about to replace all of my plugs - my Chiropractor has offered to pay for the plugs - he is pretty certain he is going to get at least 5 visits out of me from replacing those plugs...

I use the AC Delco MR43T in my boat. It's a marine resistor with a special shell. Helps keep the plug from rusting out...

dollarbill wrote:My 78 F30 Express LM318's have RN12YC and I have never questioned it. Should I use a different one? We are on 10% Ethanol here.

I am about to replace all of my plugs - my Chiropractor has offered to pay for the plugs - he is pretty certain he is going to get at least 5 visits out of me from replacing those plugs...

That is hotter than mine and I run no ethanol.... I would use cooler say 9. I believe mine is the Chrysler recommended.

What is the difference? (to a layman)

What gap are they supposed to be? I guess I should have asked questions when the mechanic changed them a two seasons ago.

Look back at my initial post all the info is there including gap!

I know this is off topic, but, just wanted to tell ready123 that's a nice pic you have in your signature.

Thanks... much love and effort has been spent on her.

I missed that. I am glad my former mechanic moved to Florida because I recall the gap being less than that on the plugs that are in there.

My info is from the Chrysler engine manual (plug type and gap).... now I use no ethanol fuel and am not sure if ethanol requires any gap change, I would not expect that but....