Small Engines (Lawn Mowers, etc.)/Craftsman


QUESTION: I have a craftsman silver 5.5 hp lawnmower with a pulsa jet carb that is only a few years old.  Starts on first pull and runs great but while cutting the grass it will suddenly sputter and blow black smoke then just before it stalls it will smooth out and run fine again.  This will happen the whole time I cut the grass.  I have a fairly small yard that takes me about 20min to a half an hour to cut.  I have pulled the carb and cleaned it.  Took out the fuel and air filter and cleaned them.  The diaphragm seems to be ok.  I even changed the spark plug nothing makes any difference at all.

Any ideas??

Feeling next to useless


ANSWER: What is the engine model, type and code number?

Does your carburetor have a primer bulb/button you push 3-5 times to start cold?

Let me know.

---------- FOLLOW-UP ----------

QUESTION: This is what I can find.

Briggs and Stratton
158cc 5.5 Ft lbs torque
Model # 944.361180

Yes it does have the primer bulb/button you push 3-5 times.

Hope this is what you need



ANSWER: Please re-check the model number.  The format seems correct but I can't find the model number.

If you Google the model number you should be able to pull up the parts diagram on Sears website.

Let me know if the model number is correct.


---------- FOLLOW-UP ----------


I verified the model number and it is correct.  I called Sears and they told me that because it is a Canadian lawn mower that I won't find manuals or parts breakdowns online.  Is there another way to do this?  I could send you pictures or explain in more detail as to what you need.  I have a strong technical background in the automotive industry so terminology should be a problem.

Thanks again Glenn

Does the carburetor prime correctly?  Does the primer bulb squirt gas?

Is the fuel intake pipe sealing?  Is it possible warped?  You can use a little Permatex 2 to ensure there are no intake leaks.

Some of the older fuel tanks would warp a little over time and cause your symptoms.  If you take the carb off the tank you can use a flat file and run it across the fuel tank base in a couple of different directions to see if it is warped.  If shiny spots are present over the entire base after a coupe of strokes the tank is not warped.  If you see shiny and dull spots then the dull spots are low and the take is warped.


Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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