Hi. I have a pretty basic side discharge lawnmower that I tried to start today. It's about 35-40º here, and I primed it with a few pushes, then pulled the cord. It started to turn over on the first pull, very slowly. About one "pop" per second, slower than I've ever heard a lawnmower engine turn over. It did this for about 10 seconds, then on the last pop, what looked like a little white explosion came out of the air filter. It then started to leak gas out of the air filter. So, I took the air filter off, and saw a little red tube with gas pouring out of it. Not sure why this was happening, and am also a bit confused as to why the fuel line is leading IN to the air filter. It's been raining here a bit so maybe water leaked in there and has something to do with it. Any help would be much appreciated, thanks.

That little red tube is an air bleed tube that feeds air into the nozzle to mix with the fuel or may be the float bowl vent. In either case if fuel is flowing out of this tube, then your carburetor is flooding. You may have a stuck float valve, or some build up in the carburetor causing the inlet needle to not seat. The float may be bad or the inlet needle and seat may need to be replaced. In any case at the very least you will need to remove the float bowl and inspect this area to see what may be causing your problem.

I'm not really experienced with 4 strokes too much. I've never taken a lawn mower apart besides changing the air filter, oil, and those basic things. A hobby of mine is r/c cars, so I've spent a good amount of time with the nitro engines that power them, but those aren't the same as 4 strokes.

My question then I guess is, where is the float bowl and the float/needle valve? Is it even possible to find my way around this engine by reading some guide or maybe through your instruction, or should I bring it in for repair?

http://www.cpdonline.com/692509.pdf

This link is for a service manual that should cover your engine. Read the carburetor section and you will find out what I was talking about in my previous post. You should be able to tell if this is something you think you could handle or not. Then you can decide if you want to attempt this yourself or take it to a shop.

Best of Luck :thumbsup: