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Summary: Identify bad spark plugs on a Polaris ATV, including a Polaris 500; learn how with tips from our expert ATV mechanic in this free ATV maintenance and repair video.
Views: 3,901 | Tags: maintenance, offroad, all-terrain-vehicle, four-wheeler, three-wheeler, all terrain vehicles
About the Expert
Tom Roland Tom Roland is a BMW, Ducati, and Polaris certified mechanic and the head mechanic at cottonwood motor sports in Cottonwood, Arizona. He currently works on ATV... read more
On behalf of Expert Village, my name is Tom Roland we are at Cottonwood Motor Sports and I am here to tell you about service on a Polaris Quad and this is a representative of macho, many of them. These three plugs are fairly representative of what we see when we pull spark plugs out of motorcycle regardless of make. This is a very good color. This has a light color insulator and it is a little dark around the outside. If we measured, the gap would measure at 28,000 and that is right where it is supposed to be. This spark plug here is slightly compromised. It is dark on inside, a little lighter on the other but it has an overall dark look to it and that usually indicates a plugged up air filter or something or maybe even a carburetor that is starting to go rich. This spark plug right here is real dark and when they start to get like that or when they get shiny, glossy or wet, they are usually fouled. If they are fouled, they may spark and people commonly go oh, it sparks. Well it may spark under compression in the cylinder it won't spark or if it does it will misfire or it will make a backfire or it will be hard to start or they won't have any power. And the spark plugs are the cheapest, easiest maintenance item other than the air filter that you can do for your vehicle and we pull spark plugs out just to get general overall idea of how the vehicle is operating. If we pull a spark plug out and it is clean like that, then that spark plug indicates that this motor is healthy and everything is all right. This one maybe it should didn't' get run very much for a while and it has been sitting and they ride it occasionally but they never really get it up to temperature. But when they are wet and they are fouled and they are really black, they have to be replaced and usually have to find out what the issue is whether it is a stuck hoke, bad gas or any number of things. That's what our job is.