resistor plug vs. standard plug

[milehighboater]

I am changing out my plugs in my 99 ELPTO and am looking at the Champion L78V but there is a resistor plug QL78V and have never heard of that one. Can someone tell me if which one I need? The motor is a Merc 1999 3 cyl 2-stroke Thanks.

 

[achris]

Re: resistor plug vs. standard plug

I am changing out my plugs in my 99 ELPTO and am looking at the Champion L78V but there is a resistor plug QL78V and have never heard of that one. Can someone tell me if which one I need? The motor is a Merc 1999 3 cyl 2-stroke Thanks.

Spark plugs!!! The world of mystery numbers...

A resistor plug has an 'R' in the number, like a BR6FS.
If there is a 'Q' or a 'Z' in the number, that is an inductive noise suppression plug.

The plugs you need for your engine are unknown, because a 1999 3 cylinder Merc 2 stroke could be anything from a 40hp to a 90hp. If you can supply the engine serial number and hp we can give you the exact plug.

You will also find that people on this forum will steer you away from chumpion... go to NGK or AC.

Chris.....

This table should help you....

 

[milehighboater]

Re: resistor plug vs. standard plug

I'm sorry about that, It is a 75 Hp ELPTO. the SN is 0E351867. Right now there is a Champion L76V in it. When I went to Iboats to pick-up the new plugs it lists a resistor and a standard plug. The Champion RL76V and the standard L76V. Just wanted to know which one to pick up. The boat it is on is a 1999 tracker 175, a 17.5 foot aluminum bass boat. Thus far I haven't had any problems, I am just replacing the plugs for PM. Speaking of which how do you know when you need to replace a surface gap plug? Oh I can tell these are factory plugs because they still have the black factory overspray from when they painted the engine.

 

[achris]

Re: resistor plug vs. standard plug

I'm sorry about that, It is a 75 Hp ELPTO. the SN is 0E351867.

That serial number comes up as a Force engine.. If it is a Force then the plug should be an NGK BUHW or BUZHW.

Speaking of which how do you know when you need to replace a surface gap plug? ....

Surface gap plugs are harder to see, but you look for a worn grooves inside the plug, on the 'ground' side and the centre electrode. (I'm draw a pic and post it in a sec..) If you use a very fine tool you can feel them.

Chris.......

Here's a cross sectional diagram of what to look for...

 

[milehighboater]

Re: resistor plug vs. standard plug

Force motor? This could pose a problem, how do I get parts for this motor? Do I dtill look under mercury parts? I will post a picture of the cowling so you can see where I get my confusion. 1999 was one of the years Tracker Marine labled the motors as "Trackers by mercury marine" I guess I just assumed it was a merc. But hey there is a good side of the confusion it took me 10 years before I needed to start looking for parts! Any help with this would be great, and thanks for the plug info it was just what I needed.

 

[DJ]

Re: resistor plug vs. standard plug

"Trackers by mercury marine" .

It's a Force. Most parts are still available.

 

[milehighboater]

Re: resistor plug vs. standard plug

Thanks for all the help on the engine type but my initial question of the difference between the standard and resistor pulgs haven't been answered. I know both Champion and NGK make both types that will work in the motor but why would someone use one over the other?

 

[achris]

Re: resistor plug vs. standard plug

A resistive plug is to reduce radio interference.