So I've brought my son a little quad I believe is Chinese , it was leakin petrol but I've solved this by bending forks inside carb bowl I also struggle to start it so I've brought a new battery it started but again can't start it after . I've noticed when I start it its tryin to pull off without Revving and when I do rev it wants to cut out , it's brand new I've taken air filter off n can see that float isn't stuk and moves freely what can this be I'm sik of it he's been on 1 time since Xmas n is askin to go out all the time pls can u help !!!

 

It also has gas leakin out filter

 

Ok lots to cover here to start with some termonology to help you understand future replys (Not being an *** just people will say check the float ect and want to be sure you get the right part)

"solved this by bending forks inside carb"
This is the float
"air filter off n can see that float isn't stuck"
Asuming you mean the cylinder shaped item with a brass needle on the bottom, this is the slide.

"I've brought a new battery it started but again can't start it after"
As in the battery will not crank the engine? or The battery turns the engine over but it won't start?

"I've noticed when I start it its tryin to pull off without Revving and when I do rev it wants to cut out" "has gas leakin out filter"
I read/replied to your post on the expert forum (I'm NOT an expert) and feel the same response still applies so i'll post it here too. That sounds like a vacuum leak. Check to make sure you didn't knock a rubber line off somewhere. If not grab a can of starting fluid and spray any rubber lines, ..outta room

 

where the carb meets the boot, boot to intake (or carb flange if yours doesn't have a boot), intake, and intake to head. If the engine changes revs then you found the leak. Simply disassemble and find out why (bad gasket/o-ring, loose bolt, ect...). You didn't mention the fuel in the air cleaner before, but it really helps me believe its a vacuum leak. Basicly your engine cannot draw air/fuel through the carb so the gas goes whichever way it feels like.

On your other post you mentioned that the electric starter 'rarely works'. As in doesn't crank the engine over? or Cranks the engine over but it won't start?

 

Thx a lot I'm new with quads but no the basics ill try wat you've said as I did take boot off a few weeks ago maybe I have a slight gap or sumat maybe it's not sealed properly also another thing I didn't mention drrrr , I did hav a loose bolt on the head which just turns and dont tighten I noticed a bit of oily residue come from here , I was considering buying a new engine as they are £40 and would probly be a easy way to solve problem !! For a brand new quad I'm not happy i suppose u get wat u pay for

 

Would a vacuum leak make it rev on its own then ? And is this why it won't accelerate

 

Thx a lot I'm new with quads but no the basics ill try wat you've said as I did take boot off a few weeks ago maybe I have a slight gap or sumat maybe it's not sealed properly also another thing I didn't mention drrrr , I did hav a loose bolt on the head which just turns and dont tighten I noticed a bit of oily residue come from here , I was considering buying a new engine as they are £40 and would probly be a easy way to solve problem !! For a brand new quad I'm not happy i suppose u get wat u pay for

 

Yes well for practical aplications.
If you boil it down an engine is basically an air pump. The fuel just provides energy for it to spin. The more air you get in relationship to fuel the better it pumps air. On the other hand a 'lean' engine runs hotter and allows room for the fuel to detonate instead of just burning. This can burn valves and blow holes in pistons. So it always a balance between performance and tearing your motor apart.

A vacuum leak just allows extra air into the mix causing a 'lean' condition. Also a vacuum leak is unrestricted where a carb isn't so it will to pull as much air as it can through there before pulling any through the carb. And since its pulling air from somewhere it shouldn't it lowers the speed/ammount of the air through the carb which is the only air that actually picks up fuel. This allows the extra fuel that wasn't picked up to spray backwards into your air filter.

 

if you are the guy who posted the pic a few weeks back it was hard to see exactly what that cover was (too close), but you may try to pull the other 3 bolts and see if you can remove the cover with the bolt still in it. If not see if the cover will spin and see if the blot has a head on it (looked like a stud to me though). If there is enough meat on the block (stripped bolt not broken tip inside you should be able to drill the hole and put a helicoil in there or just tap it for the next larger bolt.

 

Thx for your help mate I now can understand why things happen , I ain't posted no pics tho I'm new on here , gona go get my hands dirty n get this quad on the snow