Spark Plugs for 1993 Johnson 150

[Big Fish Billy]

J150ELETO I've been looking around for a couple sets of spare plugs for my motor. The book says Champion QL77JC4 (@ .030) or 828M, also seeing NGK BR9HS...just wondering what plugs you guys find work best in Johnson engines.

Thanks,

Bill

 

[boobie]

QL78YC. Set at .030 ".

 

[Big Fish Billy]

Thanks, can you tell me the difference between that one, and the one the book specify...hotter, cooler? Bill

 

[Faztbullet]

You cannot go by whats posted in manual as there are engineering updates and to find the latest always check the latest parts catalogue...

 

[emdsapmgr]

Stick with the Champions.

 

[crazy charlie]

Have same motor.Champ work well.There are 2 plugs listed according to the Johnson dealer near me.One is waaaaaaaay higher in cost than the other so they always sell me the normal priced ones.They claim to hardly ever sell the pricey ones.Gonna have to check on the plug # for you.Charlie

 

[Big Fish Billy]

Thank you, it will be interesting to know what they recommend, even for the high priced ones. Cleaning out the boat, there all kinds of different used one, I think I saw NGK BR7?????s. Once the snow gets a little lower, I'll have to look and see what's in there now.

 

[Vic.S]

J150ELETO I've been looking around for a couple sets of spare plugs for my motor. The book says Champion QL77JC4 (@ .030) or 828M, also seeing NGK BR9HS...just wondering what plugs you guys find work best in Johnson engines.

Thanks,

Bill

If you have to use NGK plugs avoid resistor plugs for OMC engines, ie those with an "R" in the number , They are often sold, even. listed as equivalent to the Champion "Q" series plugs but they are not! The Q series are inductively suppressed.

The NGK equivalents have a "Z" in the number . The equivalent of QL77JC4 is BZ7HS ( or BZ7HS-10, which are supplied gapped at 1mm)
A Grade 9 NGK plug is 2 grades too cool.

If in doubt stick with Champions although apart from in Johny-Rude world NGK plugs are the preferred option and used in almost all major outboard brands

 

[Vic.S]

Have same motor.Champ work well.There are 2 plugs listed according to the Johnson dealer near me.One is waaaaaaaay higher in cost than the other so they always sell me the normal priced ones.They claim to hardly ever sell the pricey ones.Gonna have to check on the plug # for you.Charlie

I think you will probably find that the expensive one is the inductively suppressed "Q" series plug The other probably an unsuppressed plug eg L77JC4

 

[ssportsmfg]

I have a 2001 50hp 2 cyl. When I got the boat and motor last year it had two different plugs in it, one was one of those round center electrode plugs (Platinum?) and the other was a Champion. Well of course I immediately went to the parts store and got a matching set of Champions listed in the owners manual, It was (and still is) running rough at idle, so I decided to get a set of NGK's the equivalent of the Champions, they run just as good, but not better, can't tell any difference in smoothness at idle and no difference in speed or RPM at WOT.

Guess It depends on the motor, some prefer one or the other, mine doesn't care. I only had about 3-4 hours on the Champions so checked the gap and put them in the parts box that I always carry on the water for emergency repairs.
'

 

[Seon]

I recently cruised in the ?new to me? Pontoon with a 1996 Evinrude 50hp 2 stroke that idled great but felt like it was missing at WOT. Checked the spark plug which were QL77JC4 so went to the authorized Rude/Johnson dealer who said that the correct plug used is QL78YC which I bought. I haven?t taken the Toon yet but hopefully the motor will run better.

 

[Big Fish Billy]

Yes I'm going with those too, stocking up on parts so when the snow melts below the gunnels, I'll have what I need. I bought the boat in the Fall, it ran good, but I'm one of those guys that wants at least two of everything that's eventually going to go.