Spark Plug Replacement
Moderators: BeaconMarineBob, Moderator, BeaconMarineDon
Spark Plug Replacement
Any suggestions on brand for spark plug replacement? Platinum, etc?
Cheers,
Rob & Heather McGregor
Kilts Up!
Flower Mound, TX.
1980 F-32 Express : Twin Chrysler 318's
Rob & Heather McGregor
Kilts Up!
Flower Mound, TX.
1980 F-32 Express : Twin Chrysler 318's
- ready123
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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
I use Champion XN9Y on my 318's with 35 thou gap
Michael
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL
- alexander38
- Ultimate User
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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
Carver 3607 ACMY 454's Merc's
10' Dinghy 6hp Merc.
La Dolce Vita
Let's hit the water !
http://s852.beta.photobucket.com/user/t ... 8/library/
10' Dinghy 6hp Merc.
La Dolce Vita
Let's hit the water !
http://s852.beta.photobucket.com/user/t ... 8/library/
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What is the difference of a RN12YC Champion
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 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...
- Stripermann2
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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... 

Jamie
1985 F-32 270 Crusaders
1988 Sea Ray 23 350 Merc.
Trojan. Enjoy the ride...
-I don't wanna hear anyone whine...Anymore!
-You might get there before me, but you still have to wait for me, for the fun to start!
1985 F-32 270 Crusaders
1988 Sea Ray 23 350 Merc.
Trojan. Enjoy the ride...
-I don't wanna hear anyone whine...Anymore!
-You might get there before me, but you still have to wait for me, for the fun to start!
- ready123
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Re: What is the difference of a RN12YC Champion
That is hotter than mine and I run no ethanol.... I would use cooler say 9. I believe mine is the Chrysler recommended.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...
Michael
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL
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- Registered user
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- Joined: Wed Sep 16, 2009 10:53 pm
So are those the recommended plugs for a Chrysler 318LM
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.
What gap are they supposed to be? I guess I should have asked questions when the mechanic changed them a two seasons ago.
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- Registered user
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Thanks
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.
- ready123
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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....
Michael
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL