Originally Posted By: lars11
I have not tried iridium plugs on ope but you are stating that the plug change somehow improves fuel consumption in a snow blower. Since you are running it att full throttle and there is no feedback or connection between the ignition and carb that is simply impossible unless the plugs allows you to run it at lower RPM (which I doubt, did you reduce throttle?) The carb will feed exactly the same amount of fuel to the engine at a certain rpm regardless of plug. Unless you snowblower is equipped with a full ECM this is unreasonable and more likely a seat of the pants situation. Sorry, but that is likely it.
About the tarting though, that's interesting! MAybe I will try those plugs to ease starting!
Originally Posted By: Trav
I switched everything to iridium except the lawnmower and that small plug is a B&S platinum.
I have some observations that may help you decide, nothing scientific.
My wife could not start the lawnmower ever, I had to start it. With the platinum plug she can start it first pull, same mower, same oil only the plug being different. The precious metal plugs require much lower voltage to fire, that the explanation.
The snowblower does exactly the same route every storm, again same oil (changed yearly) nothing else different. For the first 8 yrs in a storm 4 inches or more I had to refill the tank about 3/4 through, it could never finish the job without.
With the iridium it completes the job easily even in a 20+ inch storm and is still not empty. If I had to guess its doing at least 30% better on fuel (I am not saying the results in a car engine will be the same).
This thing with its algore carb runs pig rich, if you idle it for a minute and throttle back up it blew lack smoke out, now it doesn't, it idles fine. I can only attribute this again to the lower firing voltage requirement of the plug with a magneto ignition. It always started first pull and never needed the 12V electric starter.
Before I got a gas fueled generator I noticed significant improvements in fuel economy with the gasoline powered one.
I did some thinking and some research on this and the improvements in fuel economy and starting make sense.
The iridium plugs have a .4-.6 mm fine tip on the center electrode. This drops the firing voltage required to jump the gap and makes for a hotter more energetic spark, which in turn causes a bigger flame kernel that burns faster and more completely. More complete combustion = less wasted fuel in the exhaust.
The second piece of the puzzle is that yes, Trav runs his snowblower at full throttle, but every piece of OPE I’ve ever seen has a governor set around 3200-3500 RPM. The throttle control is there so you can idle the equipment.
Thus if I have improved combustion, and I’m getting more energy out of my fuel-air charge, then the governor won’t have to open the throttle plate as much to maintain the set RPM. Or you could look at it as the governor will close the throttle a bit further to avoid overspeed. Yay fuel savings.
My brother and I have predator generators. I spent $15 for two ngk BPR6EIX iridium plugs and will be installing them this weekend. I’ve run the 3200 Watt model quite a bit so I’ll post again after I’ve seen it run
