Hello. Sorry for the long post but I want to give as much detail as possible in hopes of tackling this problem.

I'm extremely handy with a wrench having swapped motors and done a top end rebuild on Polaris PWCs. However, I recently acquired a 2003 Polaris Sportsman 90 that is completely dead in the water.

The previous owner stated that it wouldn't start. I would say the stripped out kick start is evidence that they killed the battery attempting to start the ATV at some point. Anyway, when I got it the charge coil and another component (I think the CDI) were off the bike and the battery was completely toast. I have since installed a new, fully charged battery (13.0 volts at the posts), cleaned all connections on the coil and CDI, and reinstalled those components.

When I turn the key to the on position and hit what I think is the start button I get absolutely NOTHING. The tether kill switch is firmly in place and "looks" okay. There is an in-line fuse on the battery pos (+) and it is fine. Also, with the key on I get no brake lights. I disconnected the ignition harness and in the off position all combinations of pins in the harness show open circuits. When I put the key in the ON position two of the pins show a complete circuit.

I'm certain with a couple of wrenches and my multimeter I can fix this thing. The only problem is that I haven't the first clue where to start [img]i/expressions/face-icon-small-blush.gif[/img]

1) Can explain all the controls on the handle bars? [img]i/expressions/face-icon-small-confused.gif[/img] I understand the brakes, throttle, and choke levers. However, on the left side there is a red two position switch and a white momentary switch. Is the red one the run/kill switch? Is the white one the start switch? Many of the markings are rubbed off, so I can what positions these switches are suppose to be in.

2) With no activity from the start switch or even a brake light I'm guessing I have an open circuit somewhere. What would be the best place to start tracking down this wiring problem?

3) Is there a downloadable manual or troubleshooting guide that I can use for a reference?

I know with 2-strokes you simply need spark, fuel, and air and it'll run. My problem is just getting it to turn over to even see if it will run. [img]i/expressions/face-icon-small-disgusted.gif[/img]

Thanks for putting up with this newbie and I appreciate any advise you folks can give.

KJ

 

Brake lever has to be held in to allow starter to operate(small switch that goes into lever assy) also can bypass safety switch with tether by tying wires together to see if helps(they do go bad ) starter switch on bottom of left control assy. If NO TAILLIGHT when brake lever pressed AND bulb is good,then starter interlock switch(small switch in lever assy) could be bad,not making contact.Last thing check 12 volts directly to starter to see if good. Hope this helps

 

Compression?

 

<div class="FTQUOTE"><begin quote>Originally posted by: old polaris tech

Brake lever has to be held in to allow starter to operate(small switch that goes into lever assy) also can bypass safety switch with tether by tying wires together to see if helps(they do go bad ) starter switch on bottom of left control assy. If NO TAILLIGHT when brake lever pressed AND bulb is good,then starter interlock switch(small switch in lever assy) could be bad,not making contact.Last thing check 12 volts directly to starter to see if good. Hope this helps</end quote></div>

Fantastic info. Thank you very much.

Is it the front or rear brake lever that must be held to engage the starter? Also, does the brake lever need to be engaged even when using the kick start?

So then does that mean the red switch is a run/kill switch?

I haven't checked the tail light bulb but I will do that as I'm troubleshooting this.

Are any of the switches in the lever assembly replaceable or would I have to replace the entire assembly if any of them are bad?

Weedy,
I can't check compression because I'm not yet able to get the starter to engage AND the kick start is stripped. I need to purchase a new kick start arm and install that before I can even begin to think about checking the compression.

Thank you so much. I'll work with it tonight and report back my results.

KJ

 

One other thing. I noticed on the CDI (image below #13) there are two screw terminals, but there was nothing connected to them. The microfiche shows a jumper (#12) on those. Is this something I am missing and need to replace to get this running?

 

Hand Brake lever has to be held in for electric start but not for kick start. Red switch is run/kill switch. No replaceable items in control switch,replaced as an assembly. The 2 screws held the limiter plate which everyone removes to give it more power. Hope this helps

 

<div class="FTQUOTE"><begin quote>Originally posted by: old polaris tech

Hand Brake lever has to be held in for electric start but not for kick start. Red switch is run/kill switch. No replaceable items in control switch,replaced as an assembly. The 2 screws held the limiter plate which everyone removes to give it more power. Hope this helps</end quote></div>

This more than helps. Thank you VERY much.

So that jumper is just a limiter? Exactly how does it work? Does it just reduce top RPM? Obviously there's no speed or throttle sensor so I'm just curious exactly how the limiter works.

Tonight I'll have a little time to mess with it and see if I can get it to turn over. The local parts shop is okay (the service side is awful) so I'll have to call them and get a new kick start arm ordered. It looks like the splined spindle on the engine is much harder steel than the cast arm. I'm assuming it was designed that was so if anything strips, the arm is easily replaceable.

I plan to first turn the engine over with the spark plug removed and grounded so I can check for spark. That's the original problem the previous owner claimed was wrong. If I have no spark, but it turns over I will at least be able to start probing wires and get this thing diagnosed. If I do have spark then I'll know I'm looking at a fuel, air, or compression issue.

Again, thanks a bunch for giving this newbie some great info.

KJ

 

I had a little time to work with it tonight.

I disconnected the safety switch from the harness. With the tether plug in place I got a reading of 0 ohms between the leads on the switch and infinity with the plug out. Is that correct? A complete circuit allows it to fire but an open circuit kills it?

With the key ON and run switch ON I can get the brake to light up. The only problem is it only illuminates when the lever is about 1/2 way in, if you pull back any further the light goes off. So, it seems there is something not quite right with the switch. But, I would guess if the light is on, that means the start circuit is active. IS that correct? I did also notice when when the run switch is in the OFF position the brake light will not come on, so it seems that switch is operating properly.

Even though I now have power, I still cannot get the starter switch to work. With the light on I get nothing when I push the start switch. I will next try to manually jump the starter but there's only one problem: Where on earth is the starter? I've looked on both sides of the engine and I can't find it. Is it on the side opposite the kick start? Which wire do I need to hotwire to get the starter to engage?

Is there a solenoid somewhere on the chassis? Is it possible the solenoid is completely dead? What about the starter relay? Could a bad one cause this symptom? Are there certain readings I should get from my multi-meter on the relay and/or solenoid?

Thanks for the help so far. At least now I know the harness has power and I can begin isolating the problem.

KJ

 

Switch is a little plastic plunger that touches brake lever, tip is easily bent by pulling with too much force or can be shorting out. Starter is on right side of engine (small ) at near top behind cylinder.They are the usual problem about going out,but relay under seat can short out, but 95% of the ones I've seen its been the starter. Costly unless you have it rebuilt or find a different source. Thats why a lot of people just use the kick starter,which might explain why its stripped out! Starter brush kits are available,but dont seem to last as far as my experience is with em!

 

I have a pretty good shop locally that rebuilds starters of all kinds. I'll pull the starter and see about rebuilding it and getting that to work. Are there any particular tricks to removing the starter? Does the front fender section have to be removed to get to the starter or can this be done with it in place?

I think before I tear into the starter I'll disconnect the harness for starter/run switch and probe those pins. I believe I found that connector last night and it seems as though there are 4 wires in the harness: 2 for the run switch and 2 for the starter. Finding the proper pin combination for each switch should be pretty easy since I have verified the run switch is operating. I'm assuming a depressed switch should read 0 Ohms at the pins, so if that checks out I'll dive into the starter. However, if that switch is dead I'll fix that before I disassemble the starter.

I suppose there's nothing that can be done about the intermittent operation of the brake light switch? Can I just replace the harness (#19) or does the entire handle (#20) have to be replaced? The harness is $12 and the complete handle is $35.