Author Topic: Spark plug question  (Read 237 times)

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Offline Kunzelman23

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Spark plug question
« on: September 16, 2018, 09:21:55 AM »
Recently purchased 71 glastron, aero marine 350. What spark plugs would be best?

Offline Hyperacme

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Re: Spark plug question
« Reply #1 on: September 16, 2018, 09:38:48 AM »
Welcome to the forum Kunzelman23 !

Berkeley Jet & Hardin Manuals
http://forum.cgoamn.com/index.php?topic=2916.0

The Hardin manual lists 350 spec's.
Gregg
'76 CV16

Offline nes-cv23

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Re: Spark plug question
« Reply #2 on: September 16, 2018, 10:03:46 AM »
Good question... I would like to know also what everyone uses, especially in this modern word of power.  How about brands...  champ., ac, ngk, the list is long..  electrodes?   Split, rings, flat, diamond,         Just as an example.. my 86 100 hp Johnson says to use champ. L77j4.  What would a  “better” modern plug could I use?
Past to present: 84 ssv-151, 76 cvx-16 ss, 77cvx-20 jet, 90 CSS-19, 77 gt-150, 2-78 cvx-16, 79cvx-16, 79 cvz-18, 78 cv-23, 73 cv-16, 74 cv-18, 89 219 Futura, 76 gt-150 jet.

Offline nes-cv23

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Re: Spark plug question
« Reply #3 on: September 18, 2018, 06:24:19 AM »
Come on guys.... I can’t believe nobody has an option on spark plugs.?.?.  :o   
Past to present: 84 ssv-151, 76 cvx-16 ss, 77cvx-20 jet, 90 CSS-19, 77 gt-150, 2-78 cvx-16, 79cvx-16, 79 cvz-18, 78 cv-23, 73 cv-16, 74 cv-18, 89 219 Futura, 76 gt-150 jet.

Offline Plugcheck

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Re: Spark plug question
« Reply #4 on: September 18, 2018, 07:25:19 AM »
If I had one choice I'd say NGK, Bosch are good as well.  AC's are more readily available and cheaper, but don't last as long.  I developed a disliking of Champion plugs in the 70's, could put a fresh set in the Camaro, and by 1500 miles it would develop a miss.  Of course these were the pre-electronic ignition days, that might be part of the issue.  I like center gap plugs for 2-strokes.  All the plug hype with multi electrodes and such might make a difference with high performance applications, but I've never seen a difference in most cases.  I've been running ngk iridium's in the CVZ with good results.  More important is to purchase a quality plug, and don't be afraid to take a look at them every now and then.  The plugs tell a story about what's going on inside the combustion chamber, listen to what they tell you.  Plenty of guides out there, find a good one, print it, hang it on your shop wall.  Good luck.
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline Jason

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  • 1974 CV16SS, 1986 CV23
Re: Spark plug question
« Reply #5 on: September 18, 2018, 09:50:21 AM »
Only plug I've ever had issues with is Champion. I always try and use NGK and never had a problem with them. I always thought the plugs with multi-electrodes were more of a sales pitch than anything. Going with platinum or iridium seems to help with plug life. Most plugs in cars last over 100,000 miles. We'll never see that kind of use in our boats.
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline Hyperacme

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Re: Spark plug question
« Reply #6 on: September 18, 2018, 12:19:22 PM »
NGK surface gap plugs for my 1989 Mariner 115 HP outboard.
Dave did some plug testing on his V4 Johnson ..
http://forum.cgoamn.com/index.php?topic=3084.220

Do a search on forum for "Spark plugs" there's a few threads.
Gregg
'76 CV16

Offline CVX Fever

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Re: Spark plug question
« Reply #7 on: September 19, 2018, 09:09:35 PM »
I'd go with AC's if it's a GM motor. I've got 15+ seasons on the AC MR 43T plugs in one of my boats with a 350 GM engine.
« Last Edit: September 19, 2018, 09:52:37 PM by CVX Fever »
1979 CVX18 "Back in Black"....someday!
1985 CVX18 " Only thing better than 1 CVX18 is 2"

Offline fireman24mn

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Re: Spark plug question
« Reply #8 on: September 20, 2018, 10:26:28 AM »
Pretty much any thing but champion. I have put in many bad champion plugs right out of the box.

I run NGK on all my sleds, 4-wheelers, etc.
Run AC in the boat
I think this has become an addiction.


1977 CV-23 I/O Being restored
1976 CV-23 Jet
1985 Pearson MotorYacht 43ft