ok i just bought this thing the other day
the guy said it has a new top end and it starts
well on the way home we stoped by some trails and it started right up
went everywhere for about a hour or so
so we put it back on the trailer nd took it home at my house i started up nd it turned off 3 feet from the trailer then when i would crank the engine there would be a huge back fire nd white smoke out the back
well i got it to start nd left it running for a wile it was smoking like crazy
den stoped nd never started again
the guy i bought it from from told me he over filled the oil in the counter balance i dont if that is the problem?? anyone kno?
and the engines has 120pounds of compression idk if thats good??
i also tour it apart took out carb, reeds, head, nd cleaned it all
when i took out the cylinder it was brand new nd piston had new rings
but it had black oil in the crank case ??
so i drained it put everything back together
and NOTHING!!! same problem loud back fire nd white smoke but wont start
has spark getting gas only other option is timing
can someone help please :/

 

Check the exhaust for blockage

 

i did i even tryed with out the silencer and wit out side pipe

 

What did the reeds look like?
Check flywheel key.

 

gotta take out flywheel cant dont have a puller but ill try

 

reeds looked kinda open but i fliped the pedals nd they got better but should be the reeds

 

reeds might be worn out and need replacing if thier staying open. could you have flooded it while tailing it home? you said it back fires, is this while it was trying to start or is it after its running. check to make sure the etc on the throttle is set at the right gap( about 1/8") or it might be make it back fire by shutting down the engine. just a couple of thoughts.

 

it only gave me problems when i had it in my house
the reeds are not that bad my friend has the same scrambler wit reeds we glued back together lol they are bad it still rides but idles like crap
so yea mines has the oil injection blocked off but still has the lil box on the engine..
whats the etc??
my engine doesnt start at all tho
im starting to think the price was to good to be a good atv

 

hey guys thank you so much for the help and replys
really appreciate the help
i just hope i can get back to riding soon

 

Sheared flywheel key sure makes a lawn mower run like crap,if at all,with backfiring.