I just purchased a new sunl 90cc 4 wheeler and it will not start. I checked for a spark and all is well there. There is fuel comming into the carb but I cant smell it trying to burn. I have notice that there is a nickel size hole in the right corner of the cylinder block where the spark plug goes; however my other sunl has the same hole and runs fine. This quad is a christmas gift for my 7 year old. Any help would be greatly appreciated

 

WOW, don't know about any nickel sized hole. that's a new one on me.
send a pic, that's interesting. SO, i presume it turns over/cranks. you said it had spark, i presume you pulled spark plug and cranked to verify this. is this a new or used quad? if the carb has fuel and it's not getting to the cylinder, the carb/jets need to be looked at and make sure it ain't plugged up. so go ahead and clean the jets of the carb and look inside at the float. let us know.

 

The quad is used but very very new.The guy I got it from said that he started it for 5min just to ensure that it ran and from then on it would not start. Never ridden. The engine in very clean and the quad still smells of the factory oil used to lube the engine during shipping. I am very good with working on modern car ; however no clue with these small engines. A little help with how to check and clean the jets would be great. Thank you in advance.

 

Oh, the hole on the block was done during the molding process as read on a different thread fowarded directly Sunl corp.

 

here's a hyperlink for disassembly. skip down to the disassembly section and look at the pics and read it.

Disassembly and Cleaning of a Mikuni Round slide Carburetor

here's a video on how to clean the carb/jets. i do not recommend using a drill for a screwdriver though. that's your call..........

YouTube - how to clean a carb on a ATV