Spudtech Forum

Since there aren't ANY Threads on Combustion guns, I'll put this one out there. I got a threaded Grill Ignitor which comes with a piece of wire that plugs into the side of the ignitor body. I plugged that wire in and bent it around toward the tip leaving about a 1/4" gap. I clipped the wire and stripped a small bit at the end. This way when I push the button it sparks JUST like a spark plug. To mount it, I drilled an undersized hole into the combustion chamber, lubed the threads with Vasoline then heated the hole to soften it and screwed the igniter in. You can adjust how far the wire is from the tip to get the max spark. I've used it successfully with hairspray and propane but the heat of repeated firing will start to melt the plastic plug so it'll have to be replaced every 50 - 100 firings.

Hello might I suggest a method that I have used for years on almost all of my cannons. In stead of threading the ignitor into the chamber I use brass or metal screws about 3-4 in long and 1/16 dia, predrill holes in the chamber around 4 in apart be sure to angle them toward each other. You do not have to be spot on as you can just bent the bolts once there installed. Be sure to also have a few nuts to lock the bolts in place. Now you can run wire from the ignitor to the screws and make a nice handle or just use a metal door handle (like they use on sliding barn doors) these are great for two reasons, one they are a nice fit for the hands and two they are stamped as such as to have a concave outside that a 3/4 piece of PVC will fit in and you can put the ignitor in that and there you have a great thumb trigger.

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Also how often are you replacing the spark plugs, should be 20,000 miles.

The gap looks big in your photo.

Can you check at 10,000 mile oil service ?