I have a 1996 Polaris Sportsman 500 and i am having trouble with the spark on it. There is no spark to the spark plug while cranking the engine. However there is a spark to the plug when I let got of the green starter button. It only happens for a second while releasing the start button. Otherwise there is no spark going to the plug. Any body know what would cause this?

 

Several things you can check on this. See if you can pull start the machine.If you can,the pick up coil may be weak or too far from the flywheel to get a good spark when using the electric starter. Also you can pull the black wire from the reverse limiter module located under the cdi and then see if you have good spark or cranks up.These modules all fail over time and can cause problems. You also may need to check stator resistance specs. These wires lead from the stator to the cdi module.Stator exciter wires Red to Green 3.2 ohms, Black/Red to Green 450 ohms,Pick up coil White to White/Red 97 ohms. Specs are +/- 20%. Also removing the recoil cover and a simple cleaning of the pickup coil and flywheel area may solve this. Hard to keep this area clean and dry.

 

These are the OHMs readings I got using a INNOVA 3320 Digital Tester
red to green =2.6 ohm
black/red to green= 407 ohm
white to white/red= 101
The stator on it is new. But its aftermarket. the CDI module is new also. Its a red aftermarket. I still have the old CDI maybe i should put that one on again and see what happens. am also going to the parts store to get a new spark plug for this. The one i have looks good visually, but a new one probably wont hurt. I removed the pull start again and cleaned the flywheel/stator area with compressed air. everything in that area is clean. I used the pull start a bunch of times and that didnt work either. The black wire to the rev limiter is disconnected. Can the air gap between the flywheel and pickup coil be adjusted on these engines?

 

I tried using my old Polaris CDI module like i said in my previous post, and there isn't ANY spark now. But I assumed that would happen. I also know that it isn't starving for gas because i pulled the spark plug again, and it is saturated in gasoline. I also broke the pull rope for pull start unit. What a day, I should have just stayed in bed this morning.

 

New stator is good enough by your specs..Did you have any spark at all with the aftermarket cdi? In either case with the new cdi OR old cdi,pull the black kill wire from it to isolate it from the kill circuit and then see if you have spark with the new plug. If you do have spark then could be a wiring short or an ignition switch or left control switch problem. Plus a simple plug wire short to ground or in rare cases a resistor plug cap can fail. Plug cap should ohm out around 5k ohms or a tad less. Plus since you broke the pull rope I definitely would look at the pick up coil distance. Look at this members solution on his machine. May or may not help,but good info. http://forums.atvconnection.com/pola...ml#post3155476 Another common problem on the left control switches was corrosion/dirt could get into the contact points of the emergency on/off slide switch. Not a bad idea to use electrical contact cleaner,spraying the crevices of the control switch and move all the switches back and forth.Also check the wiring leading down from this switch into the terminal board for any shorts. One other thing is to check the flywheel magnets. These old models were bad on the expoxy bonding coming loose ,magnets sliding which can cause erratic ignition and if thrown loose,can tear up that new stator.

 

Finally got it going this morning! I took the headlight/override/kill switch off, and bought a brand new one. I tore the old one apart and it was filthy on the inside. The contacts for the yellow override button were terrible. and the killswitch contacts were wore bad also. Anyway that whole switch assembly is brand new from Polaris. I also re set the stator coil to .040 thousandths. The original gap was .070 thousandths plus, according to the stack of feeler gauges i was using. I ovaled out the coil holes with a small chainsaw round file so I could reset the gap. I kept it running for about 45 minutes this morning and it runs damn good! But there is some carb problems that need to be addressed. It wont stay running unless the choke lever is fully engaged. It doesnt miss a beat when it is fully engaged, but when you shut the choke of it kills the engine immediately. I'm not sure how to set the choke. the previous owner of this engine told me that carb was rebuilt. Visually the carburetor is very clean. Now to figure out the choke problem.

 

A whole lot of people overlook this switch when trouble shooting as its open spaces and cracks are just right to trap dirt and moisture on the brass parts.Cleaning with electrical contact cleaner can help sometimes,other times no,it needs to be replaced. What's happening with the choke. Does it feel like it's not opening or closing right? Is the plunger stuck? Plus if it only runs with the choke on,somethings still stopped up in the carb or if you don't have the air box and filter on,it won't run worth a flip in most cases.