full throttle "breakdown" on the 70...

[Ddw350]

during the fall my 70 started to "breakdown" at full throttle,havent fooled with it till tonight.it runs good for like 2 mins then it wont really go past 3/4 throttle.it will start to "breakdown" so to say.almost like im turning the switch on and off.ive tried the following--fresh gas--new plug--adjust points--carb swap with a known working carb--fooled with switch....could the coil stop coiling after its hot? do points go bad once there hot?? im 35 and have never understood the points/coil deal really works! guess i never really fooled with them..thanks for any help..

[james9r9r]

Well the points eventually will need to be replaced along with the condensor

[RedRider_AK]

"Coil stop coiling" That's funny. Could be the points out of adjustment. As far as I know, when your coil starts going out, it dies. Permanently. I had a snowmobile and the coil was dying on it, it would lose spark on one cylinder when it got too hot. I doubt it's the coil though.

[james9r9r]

When my points were out of time My atc 70 would start and run about 5 feet then die.

[TravEX]

Check to make sure the gas tank vent is not stopped up. Sometimes it could be something simple.

Take off the caps of the airbox to open it up and see if that helps.

If you pulled the choke on when that happens, would it help? Choke lever down, is 'off', up is 'on'.

[oOGoFastOo]

it could be a plugged fuel filter not letting the gas flow fast enough for full throttle.

[Ddw350]

i did the fuel flow thing and it did nothing, and it does it with the choke on or off,doesnt matterive set the points at several locations and results were the same,i got a spare coil i will try,might as well...i guess you call this process of elimination! i let you know what happens...

[Vealmonkey]

It could very well be the points and condenser. The points will sometimes chatter when they go bad. You should always replace the points and condenser at the same time. Coils can build up resistance and start to cut out or totally fail as they get older. Sometime, sparkplug wires when they get old will build up resistance as they warm up also. Make sure you have a secure ground point for the coil and that the ground wire is not all rusty. Points and condernser are not very expensive, but a new coil would be a bit of a cost. Good luck and if you find the problem, post the solution up here too.

[Ddw350]

now that you mention that,i did notice some "slapping" coming from under the flywheel and more sparks than normal?? dealer has them in stock,gonna get them[and condenser] friday and try it out,not very expensive like you said plus it'll be peace of mind to have new ones...

[Ddw350]

well,i spent $60 the other day for parts,got points,condenser,clutch plates,few other things...points did nothing,it almost sounds like a carb problem,after i did the carb swap,the problem was still there just a little different, i'll fool with it tomarrrow eve,its supposed to rain...

[TravEX]

Did you change the condenser too?

[Ddw350]

yes,$12.50 for it....havent fooled with it ,ive been sickly