Hello to all ATVers. I recently came across this site and decided to join. This is my first post to your forum. I’ve been an avid ATV rider since the early 80’s. I perform 90% of my own service work and have recently come across an issue that has stumped me. My friends 03’ LTZ400 recently started to act in a peculiar manner. It will start normally, run for about 10 minutes and shut off. No matter what you do it will not start again for about an hour. Here is what we have done to date and we are still facing the same issue:
· Removed tank and drained. Check operation of petcock and replaced fuel.
· Replaced plug. Plug sparks when tested even during hour shut off time
· Replaced coil
· Cleaned air filter, check for obstructions, all good
· Checked oil and coolant, both okay
· Remover carb, cleaned and replaced.
· Checked compression. All good even when bike will not starting.
· Checked for obstructed exhaust. All okay.

I suspect the problem may be either the stator or the “black box” control module. Has anyone out there experience a similar problem? I’m about ready to send it to a real shop but I’d hate to do that especially if I’m missing something simple. Like I said the bike runs normal for about 15 minutes without any indication of a mechanical problem then just shuts off. one final note: I'm finding fuel in the bottom of the air box (with oil but I suspect that washed out from the filter)

Thank you for any advise. My brain is fried trying to figure this one out…

Nimrod2k2

04' Suzuki Twin Peaks 700. Moose performance module, ITP 4 spoke rims, 27" ITP mudlites, full skid plates.
94' Ymaha Timberwolf 250
90' Honda Fortrax 300

 

Welcome nimrod. Question? Did you find fuel before and after doing some checks on the carb and all? From an outsider it sounds as if the bike is warming up and the heat is causing some kinda prob. then after it cools it starts again, only to heat up and shut down. It may not be warming up enough to cause a prob with the tank, (pressure), but try it with the cap of the fuel tank, may sound stupid but if ya can get all the "little" stuff zeroed out no matter how illrelevent you may just find the answer. ive actually had this prob with a bike before, pressure would build and it did the same thing, would shut off until cooled. found out the cap was defective, wouldnt let the pressure out which caused a prob with fuel flow, ie: too much.

 

I may be way off base here, I am not familuar with the 03, but I have an 05 that only has A res, pri, and on. on the petcock. with it set on pri. it would do the same thing you are discribing. in res. or on no problem. like I said I may be way off Base but just trying to help. I felt like an Idiot when I was told that pri ment to primm the carb. And I was flooding It.[img]i/expressions/face-icon-small-blush.gif[/img]

 

They both have good ideas. Might be the pluged vent.

If you have spark, I dont think it would be the CDI, I could be wrong.

Is there fuel in the bowl after it dies? You can check by opening the drain on the bottom of the bowl.

 

Thanks for these replys... I did the gas cap thing and that is not the problem. The petcock was taken apart, inspected, reinstalled and tested. Everything works as it should. We use Pri to fill the carb, on to use when its running. Finally, there is fuel in the carb bowl when the motor quits. I'm stumped! What vent should I be looking for? If it is the one that primes the petcock, we checked that and it is working. thanks again everyone.

Chris...

 

nimrod,

Make sure your choke actually engages and disengages. The shaft and spring that goes into the crab tends to get rusty. I know it sounds weird but check it out. I had the same issue. I traced the choke cable to the carb. Removed the hex nut. The choke assembly sound slide right out. If it doesn't its stuck. You can use a slotted screw driver and give the little brass fitting a tweak left and right. Than give it a pull. Clean it up and put a fine layer of lube on it. You should be done. Well, if its this issue...

2SS

 

pm sent

 

Well i recently went for a ride and ever since my quad would just shut off after about 1 minute , if i give it gas it revs up BUT if i rev it to quick it cuts out and shuts off . i also it seems like its getting a little hot. could any one HELP