Interesting spark plug info

[gm280]

I was watching some YouTube videos a few days ago and saw this video concerning spark plugs. And one thing caught my eye and I had to try it for myself. Seems you can easily make a resistive spark plug a non-resistive plug quite easily. I figured hearing that, it was some goofy idea and never work. However, I was wrong...again.

If you take a resistive spark pug and hold it with some pliers or even with a vice, you can heat the tip, the place where you normally snap on the spark plug boot, and twist it off without any effort. Just apply a standard blow torch and use a pliers and turn off the top. Yes it is threaded on...go figure. And once the tip is removed, you can flip the plug over and the resistor falls out. Of course wait until it cools off first to avoid burning your fingers. It is not connected with anything inside other then touching the tip and spark electrode when it is tighten on. Some times they have a little spring inside as well. And then you can simply cut a solid piece of wire from some solid home wire (10 or 12 gauge solid copper) about the same length as the resistor you removed. Then install it all back together again. And WALA a non-resistive spark plug now. It is that easy. So I had to try it and here is that picture as I took mine apart.

Here is one I took apart this morning with very little heat and unscrewed the tip. That part in the center is the resistor. Seems the factory only uses glue to hold the tips in place. I won't recommend this for anything serious, but just thought it was interesting to know. I will see how it runs on the Poulan leaf blower/vac and see if it actually runs now. IDK JMHO

 

[Boomyal]

Seems odd that they would use a resistive spark plug in a leaf blower? How would you even know whether it had a resistor or not?

 

[MTboatguy]

A good many of the plugs produced today are resistive by default, cost to much money to change the production line to run the same plugs twice, so most everything gets the resistor.

 

[mla2ofus]

Am I to suppose the only purpose of the resistor is to suppress static on AM radios?
Mike

 

[MTboatguy]

Am I to suppose the only purpose of the resistor is to suppress static on AM radios?
Mike

Actually resistor plugs suppress noise in a lot of different type of electronically control engines these days, they started out for AM radios, but they have adjusted the resistor to cover many other frequencies these days.

My Digital Inverter Generator uses resister plugs and won't run right without them.

 

[gm280]

I honestly don't know the true answer to the reason for using resistive plugs in any yard equipment. However, the RCJ6Y plug number in this situation is a resistive plug. The "R" prefix designates it as such. They do make CJ6 and CJ6Y plugs as well. And even in other heat ranges too. In fact that's what started me looking about plugs in the very first place. My Poulan leaf blower/vac, being a mere year old, wouldn't start anymore and that really angered me. It did have a two year warrantee, but we all know about such things. Yes parts are covered, but labor is not, OR labor is covered and parts are not. Pick one because you could easily buy a new one for what it would cost to have it warranted repaired.

So I started looking to see what was the cause. I of course used fresh gas, and then rebuilt the carb, but it really didn't seem to have any issues once the carb was opened up. Then I checked the spark. Nothing, not even a little anything. SOOOO, disassembly time to get to the ignition system and make certain the shut off switch was working like it is supposed and not shorted out. These Poulan blowers are really not hard to disassemble. And once I did get to the ignition system, it ohmed out perfect. So I decided to check the compression. Okay ~ 30psi or so just didn't seem right and I made the decision to tear the engine down to see why.

There were zero issues with the piston and cylinder. No scratches or wear and the ring also was free. But I ordered a new ring all the same. A mere couple dollars. The postage actually cost more then two rings cost. Well playing around with the crank with the flywheel still attached I decided to chuck up the engine block in my vice and use my Dewalt cordless to spin it up to check the ignition. That is when I isolated the bad plug. I know I should have tried a new plug earlier on, but honestly I've never ever had a bad plug in my life...ever...on anything. But I did this time. All the other plugs I had laying around and even my spark tester adapter worked without issue. But this one plug would not spark even with the gap closed up near shorted. So my first bad plug in my life now. Yes lesson learned.

But that lead me to You Tube to watch spark plug videos and I found the resistor remover idea. And yes the tip does unscrew once the glue is heated up to release the tip. And yes the resistor does simply fall out as well. So now I am going to see if the solid copper replacement stud will work.

I already fixed the Poulan blower and it seems to work fine again. Still haven't tested the compression now that it is reassembled. Wonder what it reads? IDK. Some 2-cycke videos suggested 150psi. But I don't think this Poulan blower ever read that much.

So there is the back ground story about how I stumbled on the resistor removal from such plugs. I am now using a RCJ8Y plug in the blower. WHY? Because I had a new one laying around. And there are differences between resistive and suppresser type spark plugs. Obviously resistive plug have the actual resistive plug/stub installed inside. But suppressor types use a wire wound insert as a suppressor setup. While they both can do similar things, there are reasons to make certain if your engine calls for a suppressor type, to use that type. The electronic ignition system is design for a suppressor type plug and swapping a resistor type instead could compromise the ignition system. It gets into a lot more electronic theory then I care to go into here and now. Hope that explains it for you all. JMHO!