Hi guys and gals,
I'm new to the board and I'm looking for some help with my 2002 Scrambler. I got the ATV from work, as I work at an autobody shop that does towing for the town we're in. The bike came in as a police impound and was never claimed so I ended up with it for free...

Anyways, the bike sat in our storage yard for almost six months before it was messed with here. We pulled it in once we got the police release saying that we now own it and tried to start it. We replaced the battery and spark plug beforehand, with no luck getting it to start. My mechanic at the shop was slow from normal business last week so I had him tear into it to see what he could find. We don't have a compression tester here, but while he had the head off inspecting everything we put some fluid in the cylinder to see if it would leak down, and it did not. We replaced the head gasket, put the bike back together and bam! The bike fired right up and sounded great. We buzzed it around the yard a few times and put it away thinking it was fixed. A few days later we got it back out and it wouldn't start. We cranked it until the battery was too low to turn it over fast enough to start and let it sit again. The next day we recharged the battery and it started again just fine. Then we let it sit over night and now it wont start AGAIN.

Since then we pulled the plug to verify we have good spark and we do. The plug was also wet, indicating it was getting fuel. So I'm at a loss now. I know it's getting spark, air, and fuel and it wont start. The weird thing is that it runs great when it does start, so I don't think it's a valve or compression problem.

Does anyone have any ideas to help me out???

Sorry for the long read....

 

When you get it running again check to see if it's charging 14 volts back to the battery. If not pop the front panel and check the wires going into the regulator to see if any are disconnected. They were bad on this also. If all wires are plugged in and not charging then it's possible the regulator is faulty. Here's a place that's fairly cheap.Polaris ATV Rectifier Regulator
Another thing is starting to be a problem on the older machines is that it will recoil start,but hard to electric start. Sometimes trash,etc accumulates on the stator pickup coil and needs to be cleaned up along with any rust,corrosion on the flywheel. Just pull the recoil cover to expose the flywheel and pickup coil. Plus here's info from another member on his problems that he solved.http://forums.atvconnection.com/pola...ml#post3155476

 

Thanks for the tips.. I have tried several times to get it running again, with no luck. I have also verified that it is getting spark with the starter. I tried pull starting it also with no luck..

 

When the mechanic installed a new head gasket are you sure the cam timing is correct,valve settings ok,plus is the cam detent lever operating correctly? It aids in starting by opening the exhaust valves a little so the engine can turn over faster.Plus the basics like cleaning the carb,replacing worn parts,dirty air filter,etc

 

Im pretty sure the timing is correct. I saw him lining up the marks when he was putting it back together. I dont know about the cam lever... How do I check that?

Also, the air filter looks like a brand new K&N cone filter. The weird thing is that when it starts it runs really good, so I don't think its a carb issue but I guess I could be wrong.

 

To check that the detent lever and spring are correct is to first clamp off the hose leading back to the radiator from the thermostat housing.The thermostat and housing have to be removed to get to the cam plate. Remove the cam cover plate and see if the lever springs back when you lift it. If the spring isn't on properly, the 500 can be a bear to start easily. Plus I'm not a big fan of a K&N filter especially if it it doesn't have a sock over it and if it hasn't been maintained properly. An impounded, unclaimed machine kinda tells you something right off. That someone possibly abused it or didn't think enough of it to claim it.Best to down load a pdf manual or get a hard copy so you can eliminate items one step at a time on a machine like this.Hopefully it's a simple fix like the detent or minor carb problem.

 

I'll look into that stuff as soon as I get a break from work. I hope it's something simple, but doubt it will be.. Most impounds we get are not claimed because the owners can't prove ownership. Most of the ATVs around here are privately sold without titles or certificate of origins. We have gotten some nice stuff on impounds that people can never get back, and if we return stuff to them without the proof of ownership we get in deep trouble with the town.

 

I was able to look intoma fewnthings tonight. I popped the valve cover and off and checked the valaves first. The valves on the bottom, which i think are the exhaust valves(?), were spot on at .006. The top valves were tight. I had no chance of getting the .006 feeler gauge in there. I didnt check the actual clearance but went ahead and just set them at .006.

I also pullednthe carb and im gonnantry to get itndisassembledmand cleaned in the next few days.

I found a ground cable that was undone on top pf the engine to the frame so i hooked it back up. That got me thinking to check for spark again. I turned the key and it had spark but i decided to keep cranking it a bit and it stopped sparking. So i at least know now its not running because lack of spark.

Where should i start first looking for the reason why it has no spark???

 

Remove the recoil cover and check that the pickup coil and flywheel area are clean from any dirt or debis. Could be some of the problem.#13 and #19. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse

 

Thanks OPT. Glad you were able to read what i wrote... My grammar was terrible. Typing on an ipad is a real pain....