QuestionQUESTION: I have a Craftsman High Performance 19hp Kolher Courage riding lawnmower that was working fine last fall. I drove it into the storage shed last year and it had NOT been used all winter.
Today March 20, 2011, I attempted to start it up and us it the for first time this season. After stating, the engine would only run a short time and shut off, it did this two times, so I checked the fuel and topped it off, checked the oil level and it was fine.
Started the engine one more time, and again after running a short time the engine shut off, this time I noticed lots of smoke coming from the exhaust. There was also some smoke coming out of the exhaust the two other times, however I just thought the some was because the engine had not been run since last fall. On closer inspection I noticed lots of oil coming out of the exhaust and a buildup of oil under the front of the engine.
My guess is something is wrong with the internal part of the engine, causing oil to escape with the exhaust and the oil pressure then drops and the LOW oil pressure switch kills the engine.
I have read something about a blocked breather causing a similar problem, there have been mud-dauber wasps in the building?
Again, the engine was working fine the last time it was used.
What could the cause be for this type of failure, the oil to be coming out of the exhaust and the oil pressure dropping?
Craftsman High Performance with 19hp Kohler Courage
Model No:917.275180
Serial No: 062405D01212074
19hp Kohler Courage
Spec. no. PS-SV590-0004
Family: 5KHXS.5972GB
Serial No: 3515100083
Serial #: 3515100083
ANSWER: Jon
The cause is the float in the carburetor may be stuck causing fuel to leak in to the valves or into the piston area If this has been setting the fuel shut off may have been left open.The reason you are seeing the smoke is because For the most part, smoking is just as bad for a small engine as it is for you. Excessive smoke from the engine may be an indication of problems with the carburetor, rings, or gasoline:
Black smoke is a symptom of an overly rich fuel-air mixture. This could be caused by a choke that is partially closed, a faulty carburetor, or the need for a carburetor adjustment. Make sure the choke if fully open. See the sections on carburetor adjustment and carburetor cleaning.
White or black smoke may also result from yard debris, oil, or other contaminants on the exterior of the cylinder as the temperature after a few minutes of operation will reach several hundred degrees F even with proper cooling. Stop the engine and let it cool for a few minutes. Then, check around the cylinder, cylinder head, and under the shroud for grass clippings, leaves, oil or other spills, dead rodents, etc.
2 stroke engines will always produce some fine white/blue smoke since the lubricating oil in the fuel mixture is being burnt along with the gasoline. However, excessive white/blue smoke could indicate an incorrect ratio of gasoline to oil or a mixture which has been sitting around for a while - the more volatile gasoline evaporates leaving behind the oil. It could also be an indication of contaminated fuel.
4 stroke engines should produce virtually no smoke while running. At first startup of the season, there may be a few seconds of white/blue smoke resulting from the oil squirted into the cylinder at the end of last season (you did the preventive maintenance, right?) burning off as well as white smoke/steam from accumulated moisture. If you tip the mower on its side routinely (to clean out grass clippings, for example), oil may seep into the cylinder resulting in white/blue smoke at startup as well.
White or blue smoke while running may be an indication of an excessively worn cylinder or rings or a clogged or inoperative breather (the breather assures that there is always negative pressure in the crankcase - if not, oil can get forced up into the cylinder). Or, you may be using the fuel mixture for your 2 stroke weed whacker by mistake!
---------- FOLLOW-UP ----------
QUESTION: After stating, the engine would only run a short time and shut off, it did this two times, so I checked the fuel and topped it off, checked the oil level and it was fine.
Yes the engines is blowing lots of smoke and oil out of the exhaust, however the engine keeps shutting down after 45 seconds.
This shut down could be the result of LOW OIL PRESSURE, and the switch shutting down the engine.
How could:
"the float in the carburetor may be stuck causing fuel to leak in to the valves or into the piston area If this has been setting the fuel shut off may have been left open".
Cause the low oil pressure?
I think something else could be wrong, I don't think the float stuck could cause low oil pressure?
Also, thinking back on it, I may have heard a loud POP (backfire) when I turned the key off the last time I parked the mower, what would cause that?
And could that have caused something like a PUSH ROD to have bent?
AnswerJon
Low oil pressure will cause the engine to shut off as far as the carburetor is concerned yes that can cause fuel to leak into the engine area causing the smoke and the low oil pressure as that carburetor has a float and it is not uncommon to have the float bounce around and letting fuel leaking in the cylinders. When a mower is stored for the winter season fuel has a tendency to evaporate todays fuel is produced with a lot of alcohol and you know that if that happens you are left with junk and build up in the carb. When yo start using it you put fresh fuel in the tank and stir up any residue left over,which will eventually get to the carb.You also could have a blow head gasket. yes a bent push rod would cause a back firing as well as a bad fuel solenoid, when you kill the key switch the solenoid close the fuel shut off to prevent back firing or engine after burn.Sorry, But I'm just about out of ideas on this one without being able to see or put my hands on it
