gas blowing out exhaust any sugestions?

[johann]

Hello,


I am having problems with gas (and now oil) blowing out exhaust at start up. It used to only be once in a while when I start,and then it would run like a top. It has become more frequent and now once in a while it will smoke some oil too. tonight though it poured out, and smoked really thick blue oil smoke and then white, and then black. would start for a few seconds, almost clear out and then go back to spewing smoke and gas. it is a 10 year old John Deere/Scotts garden tractor. 16 HP Kohler, 42" deck.It has for the most part had very few little problems, and until this year. it worked all year round , grass, totin' trailers, plowing snow. It is now just for mowing .....unless today was the last time it plans to run. I havn't ever had a machine do that before I am hoping some one here knows what might be going on with it.

 

[rekees4300]

Check the level of the oil because the engine may be too full and the excess oil may be being burning. If this is the problem, then drain some of the oil out until the dipstick measures it as being just full or slightly below.

 

[mmurphy]

Air filter clogged, float on high side, choke not opening all the way. Just a few thoughts.

 

[johann]

I do have the oil at proper level,I had the air filter off because I had mice building a nest in between the motor and the top case , so I wanted to make sure they did not get in the air filter. The float too high does make me wonder if some of the nest debris did get in to the carb on start up even though the nest was on top of the motor......

 

[oldnslo]

Hello,


I am having problems with gas (and now oil) blowing out exhaust at start up. It used to only be once in a while when I start,and then it would run like a top. It has become more frequent and now once in a while it will smoke some oil too. tonight though it poured out, and smoked really thick blue oil smoke and then white, and then black. would start for a few seconds, almost clear out and then go back to spewing smoke and gas. it is a 10 year old John Deere/Scotts garden tractor. 16 HP Kohler, 42" deck.It has for the most part had very few little problems, and until this year. it worked all year round , grass, totin' trailers, plowing snow. It is now just for mowing .....unless today was the last time it plans to run. I havn't ever had a machine do that before I am hoping some one here knows what might be going on with it.

Is this carb gravity fed or do you have a fuel pump?

If fuel pump sounds like the float needle is warn or stuck slightly open allowing the engine to flood out.

Gravity fed: On some models if the float needle wears or leaks in can fill the intake tract with fuel and on some engines, mostly Briggs it will also fill the crank case with fuel.

Good luck

Roy

 

[johann]

I don't know if it is a gravity fed or not, I am hoping to get back to working on it tomorrow. It sounds like from what your saying that I probably should change the oil in case I am getting gas into the crank case.

 

[jsb2b]

Oil and gas are separated in an engine by the valve guide seals. One or both may have cracked or worn out over time. Blue smoke is oil. Black smoke is gas. White is water vapor. Did someone (helpful son?) possibly pour oil in your gas tank?

You may want to check for and test the crankcase breather too. It's just a hose from the carb to a wire mesh filled steel rectangular box bolted to the crankcase. It should not be saturated with oil.

I had a Kohler in an Ariens tractor that would show a very fine mist of oil out the front of the crankshaft seal even with a clean crankcase breather so there is some amount crankcase pressure. Possibly it is high enough to force oil into the carb. I had to replace the crankshaft seal.

 

[johann]

I did not get to work on it yesterday, I do have it on a trickle charger on it to get the battery back up to where it should be.I will have to check for that crankcase breather. When I went out to check on the battery it had some more gas/oil mix on the floor under the exhaust pipe, I don't know if it is just left over from before or if it is still just slowly coming out of the motor.

 

[greasemonkeyok]

Fuel on the cylinder wall washes the oil off, and rings moving without sufficient lubrication scores the cylinder wall. Change the oil before you try to start it again.