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Rex L.
Rex L., Small Engine Technician
Category: Small Engine
Satisfied Customers: 761
Experience:  auto-diesel graduate. small engine and John deere and silver certified in stihl.
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LA100 riding mower. Replaced fuel pump, cleaned ,

Customer Question

LA100 riding mower. Replaced fuel pump, cleaned carburetor, new gas, belts... Rides a few yards then coughs and pops black smoke, then rides on. Does continually. Ideas?
Submitted: 2 years ago.
Category: Small Engine
Expert:  Rex L. replied 2 years ago.
You may want to try a new spark plug first. Make sure air filter is clean. It may be possible it will need a new carb. If you have a spark tester you can run it with it on and then when it coughs you can see if it is losing spark. Make sure your seat switch is also good. If you are running on rough ground and the seat switch is not working or losing connection it will try to kill the engine.
Customer: replied 2 years ago.
Filter good; carb cleaned-- twice. Spark plug new. Not switch as it also does on idle... Runs a bit, coughs, spits puff black smoke.
Expert:  Rex L. replied 2 years ago.
If you have the briggs engine you may want to check the valve lash and make sure it is correct. Should be set at .004 with piston on TDC. Also look at the push rods and make sure one isn't bent.
Customer: replied 2 years ago.
Thanks... Will check both of these things.
Expert:  Rex L. replied 2 years ago.
Your welcome.