1999 scrambler 500 4WD

getting spark, it will crank, but shuts off after 5 - 10 of running, then can't crank again for about 5 minutes.

 

try taking an air compressor with a airgun and when the bike quits, shoot some air acrossthe CDI box and try again. if it starts sooner than the 5 minute benchmark you have, your cdi is fried

 

well it cut off and i had a water hose so i sprayed it with cold water and it cranked for about 30 sec would u say replace cdi

 

before you replace the cdi i would check for a loose ground somewhere. might as well check the cheap stuff first. carefully scrutinize every wire for rubbing against the frame, loose connections or bad grounds. sometimes a bad wire can cause havoc too.

 

ok sorry to bother you so much,but its not a fuel prob;i had power to coil when running.when it shut off,i put a test light from cdi power to coil turn key on and push sart button no power when i tried to start please help'''''''

 

in your last post you said it cranked for about 30 seconds.
did you mean it started for about 30 seconds then died or the motor would turn over with the starter for 30 seconds and it never fired then the starter stopped turning?

we already know its not a fuel problem but it is an electrical problem somewhere. check all grounds to make sure nothing is loose. a bad ground on a cdi or coil will cause it to over heat.

 

Replaced CDI didn't fix the prob. Still no power going to the coil...next to CDI. Still cranks and runs, the more gas I give, the quicker it cuts off. Takes a few minutes to get it to crank back up. Could there be a prob with coil pulser? Running out of $$$.....

 

Ohm out pulser(usually white and red/white wire) that hooks into cdi. On average should be about 97 ohms give or take 20%,charge(source) coil leads usually red and red/black wires, should show somewhere around 440 ohms? Remove recoil case,visually check pulser leads if out of spec or no readings,could be just pinched wire leading into stator. Plus check wires to ground,should NOT register any readings if so,then possible short in stator.

 

ok I tested the white and red/white my reading was 77 ohms. With just key on ,swtch on,Ichecked red and red/black my reading was 307. I noticed minor rust on the grounds on coil. Have not yet removed coil case. SCARED. Although my pullrope for pullstart has been missing for years, the hole has been duct taped. could there possibly be rust behind recoil case which could be causing a problem in stator?

 

DONT be scared,just remove recoil case,then can see more about what you can do if any thing. Could be lot of corrosion around stator to clean if can remove flywheel and also pulser face and outside of flywheel area. If specs still the same,sounds like close to limit,could be cause of erratic operation. Resistance specs should be taken with wires unplugged from cdi and key off! Good luck