ATC90 with problems

[ATC90guy]

Howdy folks,
I have a Honda ATC-90 that somebody gave me free. The engine has been rebuilt and it's in good shape. All I had to do was time it and install the camshaft and other adjustments. The thing has ran great so far but today it just quit. I pulled the spark plug and it's wet with fuel. I have spark at the plug, bright and blue. When I try to start it, it tries to start and backfires once and blows black smoke out the tailpipe. I rattled my brain on this one and can't figure it out. :confused: Please help! Thanks!

[faf_racing]

I say carb and you have choke problems!

[ATC90guy]

faf:
I'm still learning here and am not a master mechanic by any means. You're saying I have carb and choke problems, but my spark plug is wet with fuel. Does that mean it may be flooding or I'm not getting enough fuel to fire off? Thanks for the help!

[ATC90guy]

Oh I forgot to say that I took the filter screen cover off the side of the carb and found a bunch of rust. I cleaned it with gas, replaced it and it still wouldn't start. I turned the fuel drain knob to see if there was gas in the fuel bowl and fuel did drain out. It also seemed to bog down in higher rpm and gears. I am thinking maybe the float is off but when I went through the carb when I got the thing it seemed to be ok. Anybody have a spec on what the float level should be? I had a manual from the library but I had to turn it in. I will get it back though. Thanks!

[faf_racing]

yes see I said carb problems, filter screen had rust in it,so the tank probably does too... and rust went into the carb..... so take the carb off and clean it with carb cleaner spray in all the jet cracks and crevices, even let it soak for a couple of hours and definatly take the float pin out and clean it real good. I dont know the float setting for that. and make sure you work the choke up/down or in/out too get the tarnish/gum too free up.... I hope this will help for now and work if not you may be looking at a rebuild kit for it.... shoulndt cost much for one.......

[IceDude]

I would deffinately have to ask if when the carb is apart...if you move the float up and down is the needle going with it b/c if the needle gets stuck down good enough to hold the floats down it will severley flood the motor and also check to make sure the floats move freely on the pin but also make sure that the pin cannot move freely in the rest of the carb;thus resulting in the pin falling partially out, resulting in extreme flooding(happened to my 90).