My 9.8 has a crankcase full of gas. Left fuel line attached and looks like gas blew into unit. Can I just drain and refill with new oil or do I need to do more?

The fill plug is on backside of engine, dip stick is on front. Page 3 page 8. If the carb float does not shut off you need to replace carb, this will stop fuel from flowing and into engine oil.

http://kohlerengines.com/engines/onlinecatalog/pdf/OM_3000_SERIES_18_590_09_REV_A_English.pdf

Drain the crankcase via the bottom most plug. Refill based on full mark on the oil level dip stick. An over full condition can result in hydro-lock of the engine causing internal damage. Do not overfill engine oil

Did you remove the spark plugs and drain the fuel from the cylinders? The gas in the oil was definitely a sign that the oil needed draining and replacement, but the pull start may be hydro-locked in the cylinders are full of fuel.

Please do not yell, and please proofread before posting.

My guess it was on it's side, oil from the crankcase slipped past the rings and the valve into the tank. Other guess is you have way too much oil in the crankcase. Drain it out the tank via the condensate drain. If you want to clean the tank, only use nonflammable cleaners. Look at the brake cleaner row in a car parts store. Remove the drain screw. Spray a lot in the tank. Swish it around, drain. Repeat till what drains out is oil free. Drain and refill the oil in the crankcase to the fill line, or to the required amount per the owners manual.

IT is likely that the carb is leaking fuel and filling the crankcase with fuel. Causing excessive crankcase pressure forcing oil into airbox through the crankcase vent. Check your crankcase for fuel and/ or being overfilled. If fuel is present fix the carb first, then drain and refill crankcase. After all is fixed run the unit outside for a few minutes and let it burn off excess smoke.

no you have to drop your gas tank clean it out. if you didn't start then just clean gas lines. if you started it then you need a new engine. the sugar gets in the engine and turns to syrup. bad engine.

When the float in the carb sticks, it allows fuel to drain into the cylinder, that runs pass the rings into the crankcase. When the crankcase is full the pistons cannot go down, and the starter won't turn the engine. Drain all the oil gas mixture, and refill with proper oil. Replace float, needle and seat in the carb bowl. Throughly clean fuel passages, and bowl. If motor won't turn, remove spark plug and turn over engine a few times to remove gas oil mixture from the cylinder too.

Sounds like your rings are either stuck or broke. Check the compression, it's probably low or non existant on at least one cylinder. In either case it sounds like a tear down.

Many times a dirty air filter will cause this on this style of engine. When the filter is plugged, it creates a 'rich' fuel condition, and the engine smokes heavily, the excess carbon is drawn into the air filter, and plugs it even more.

check spark plugs, air filter, fuel filter, choke linkages (for full choke/no choke operation) and crankcase oil.

Crankcase oil can become fuel contaminated, thus overfilling the crankcase and filling the crankcase breather with raw oil/fuel, and this is drawn into the air filter, plugging it, and starting this senerio.

If there is fuel in the crankcase oil, drain completely, and refill with fresh oil. Then you need to look towards the carb for an inlet needle sticking, broken, worn.

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leave the cap cracked open slighlty as to assure no pressure builds, and if the problem accures during that time your problem is somewhere else