I put new oil in my Lawn Mower now it smoking white

I have a mix of both sometimes its blue other times its white, it fires up and there's a big puff of white smoke then turns off

First, make sure you are getting fuel to the engine. If your engine has a fuel pump which is a small black circular mechanism mounted to the engine itself. It has 3 fuel line bibs. One runs from the fuel tank to the suction bib on the pump, the fuel line bib on the bottom of the pump runs to the intank/ valve cover-this line is usually very short and must be fitted snuggly inside the cover, the 3rd fuel line bib run from the pump to the engine/ carb. You can check if your pump is working properly by disconnecting the fuel line from the discharge side of the pump and turning the key cranking the motor. fuel should flow under pressure as motor is turning over. If not it is possible the pump has lost prime due to a dirty fuel filter. you can prime the pump by disconnecting the suction line and putting it under vacuum using a small vacuum pump or simply blowing air back into the tank creating back siphonage. When fuel begins flowing from the line quickly reconnect. I should say before going through all this make sure there is a fuel problem by spraying starting fluid into carb. If engine starts and the dies it is not getting fuel. Also check the plugs for fouling. I hope I didn't overcomplicate matters. Just trying to help.

if he wasn't getting fuel it would not start to create the big puff of smoke ... just saying

With a level intake, when the float needle(in the carb) leaks it gas will leak into the intake and the engine. As it's just sitting there it fills the engine with gas. Sometimes it will leak so much that your mower will start leaking oil. It thins out the oil and your engine will end up blown up.

I saw a mistake in my answe, if its a spill on exhaust it will smoke not die. Thank you

I found a simple explanation/solution The oil reservoir cap was not secure. My lawnmower (toro) is rather old but still runs fine. The oil cap:rim can get a bit messy; it’s easy to miss that final notch that keeps the cap snug. No more air in oil reservoir = no more smoke

oh man, this sounds spot on to my situation. Thanks for posting, Grady!!!!!!

This exact thing happened to me too. Now it starts up, but has been smoking a lot when it runs. Should I be concerned about the smoke?

I am working through the exact same situation right now. I replaced the carb float, float needle, and bowl. After I put it back together the mower only ran for about 10 seconds then it stopped. A friend told me to replace the oil. The oil had LOTS of gas in it. Now the mower starts great and runs. BUT after about 10 seconds white smoke starts coming out of the exhaust slowly, then it gets thicker and thicker. Trying to figure out whats going on.

Same here...first start up of season new fuel on old , starts up intermittent white smoke but doesnt cut out. Left it for 3 days start it up ...good as gold!

Is it harmful to the mower, walk behind type, when the smoking won't stop and I continue to mow?

I bet the fuel needle in the carb is off the seat and letting the fuel dump into the crankcase. It will hydraulic the piston and not let the engine crank. If the oil looks milky white it is getting fuel in the oil.

[image|1461783] Bad Spark Plug

Got A John Deere rider mower...cutting grass then all a sudden whitish smoke comes out like a campfire but no noises i.e. knocking/metal on metal noises....im FREAKING OUT....oil is NOT milky....I hope it's something simple....HELP...port saint Lucie, fl

I had the same problem. It was simply a bit too much oil in the crankcase after changing the oil and the oil filter. Drained off a small amount and she was fine. From now on when I change the oil I will add exactly the specified amount and not just guess. With fresh oil is difficult to gauge the amount by what's on the dip stick because it a very light colour, unlike when it's been in use for 20 hours and develops some colour.