Champion Plug Cross Reference

D

DJ

Guest
My engine calls for L77J4 Champion plugs. One source says they are not available and to use L77JC4. Has the L77J4 been superceded?<br /><br />It is my understanding that the "C" should not be used in place of the L77J4.<br /><br />The engine is a 1983 90 HP. Evinrude.
 

Hooty

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Oct 2, 2001
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Re: Champion Plug Cross Reference

Hey djohns19,<br /><br />I use the L77JC4 in my V6 'rude. Have for years. No problems.<br /><br />g'luck & c/6<br /><br />Hooty
 

seahorse5

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Jan 24, 2002
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Re: Champion Plug Cross Reference

Your V4 will run better if you use the factory recommended QL82C Champion plugs. They are a bit hotter than the L77's and foul less.
 

scotiany

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Aug 3, 2002
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Re: Champion Plug Cross Reference

On the same note, I've asked this before but I can't seem to find the reply. What is the replacement for the Champion L4J.
 

jegervais

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Jan 18, 2002
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Re: Champion Plug Cross Reference

Scotiany - L4J goes to L82C (found it in Champion book, under discontinued plug section).<br /><br />djohns - shouldn't use "YC" suffix plugs in engine calling for "C" suffix. The Y plug has extended tip, which will hit the deflector dome on a cross flow piston.<br /><br />BTW - the L77J4 did supercede to the L77JC4 found it in the same place...<br /><br />-John
 

Dhadley

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Feb 4, 2001
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Re: Champion Plug Cross Reference

Yes, the L77J4 was replaced by the L77JC4. They will work great in your motor. You can use the QL77JC4's also if you need a resistor plug.<br /><br />The QL82C's will work also but personally I like to fudge combustion temps on the cool side.<br /><br />Now if you make an error (hurring too much) at the race and grab the QL82YC'S (meant for the looper) and throw them in the crossflow, after you make a pass at 7000 you will have a plug gap of .009" and be a bit down on power.<br /><br />Trust me.
 

carmangary1

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May 11, 2003
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Re: Champion Plug Cross Reference

A bit off the subject but does anyone know the diffence between the L77V and the L76V sparkplugs? My engine calls for L77V but I put some L76V plugs in it by mistake.
 

roscoe

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Oct 30, 2002
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Re: Champion Plug Cross Reference

Carman, start a new topic with this, you will get more responses.
 

jegervais

Chief Petty Officer
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Jan 18, 2002
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Re: Champion Plug Cross Reference

With Champion brand plugs, the higher the number, the "hotter" the plug.<br /><br />John
 

carmangary1

Seaman
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May 11, 2003
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Re: Champion Plug Cross Reference

What does it mean to be "hotter"? I've heard the term before in regards to sparkplugs but I am not sure what it means.<br /><br />Thanks,<br />Gary
 

jim dozier

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Jan 8, 2003
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1,970
Re: Champion Plug Cross Reference

I believe it has to due with the length of the insulator around the electrode and the ability of the plug to dissipate heat. I think a smaller insulator cools faster, or maybe its the other wayround I forget.
 

Paul Moir

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Nov 5, 2002
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Re: Champion Plug Cross Reference

The longer the porcailan nose, the slower the nose cools to the treads, the hotter the plug. Hotter plugs carbon foul less. Colder plugs don't cause detonation. <br />Very generally speaking, if you run flat racing out all the time, you _might_ want a colder plug to stave off detonation originating at the spark plug tip.<br />Look at the buisness end of a couple different spark plugs and you'll see what I mean.
 

Boatist

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Apr 22, 2002
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Re: Champion Plug Cross Reference

Djohns<br />I belive the C in champ plugs just means has a copper core and it will function over a wider heat range. My Johnson came new with a L7J which is no longer made. At a very good automotive shop they found a old cross refference that crossed to a L82C many here on this board say it also corsses to a L77J4 but I have not found that in a cross reverence anywhere. I actually run a L90C in my motor which is two heat ranges hoter than L82C but this motor used mainly for trolling. <br />Main thing is make sure the reach is same as your L77J4. Actually all Champ pulgs go by a number now the L82C is a 320. They do still put the old L77J4 on the box.
 

scotiany

Senior Chief Petty Officer
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Re: Champion Plug Cross Reference

John from Ill-Thanks for info-needed that.
 
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