[jameslr]

I have a Craftsman riding mower with a 19 hp briggs and stratton model 407777-0124-e1. It is about 10-12 years old and I'm the second owner. The problem is the mower will run, but only at half choke. Even at half choke it sounds like it's about to die, and if I go through any grass high enough with the blades engaged it will die. Any ideas?

I realize this could be a multitude of problems associated with the fuel system. I've checked the fuel filter and it is filled with fuel and looks clean. I had the entire fuel system ripped apart by a friend that is mechanically inclined and he cleaned everything, replaced spark plug, cleaned air breather. I have read it could be the exhaust. When I first start the mower after it sits for a while it smokes a bit like it's burning oil. I checked the oil and it was about a half quart low, and there's some oil spatter under the engine block.

Is there some easy to check stuff that I could do myself that doesn't require a great deal of knowledge / experience to perform? I'm not a mechanic, but I'm not a dummy. I can follow instructions and I'm eager to learn. What are the top 5 things you would check first with these symptoms?

 

[matt167]

Pulling the choke means it's lean. See if you can feed it some propane thru the air intake (unlit propane torch ) and it might run better. If it does, that usually means you have a vacuum leak or a problem with a clogged jet.. If it runs better that way, get it running really strong with the propane and open choke and quickly put your hand over the intake but don't let it die. It may provide enough suction that it clears the jet. If that does not work, the fuel bowl needs to come off the carb but you need to be prepared for the needle to fall out and not loose it ( or be prepared to buy a new 1 ). After that, you can clean the carburator out with carburator cleaner, put it back togther and see if what you did worked.

 

[jameslr]

Thanks for the suggestion Matt. I think I have a small propane bottle around here somewhere that I used for a small hibachi grill, but I don't have a torch nozzle for it. I'll have to pick one up at the hardware store. I'll let you know how it turns out though.

 

[tomw0]

A quick check for fuel flow is to remove the float bowl, or loosen the fastener. {1/2" mostly} and see if fuel drizzles out. Be prepared to collect it with a shallow pan.
If you have an electric connection to the float bowl, you likely have a shutoff solenoid valve at the bottom of the float bowl that springs closed when the key is turned to OFF. It is designed to prevent 'run on' by interrupting the fuel flow when the engine is stopped. It will NOT stop flow into the float bowl. The solenoid can get gummed up, and fail to retract the pintle. The fuel can slowly leak a bit into the carb passages, enough to cough & spit, and maybe run for a few seconds. So, check for fuel in the bowl, and flow when the bolt is loosened. Listen for a click at the solenoid when the key is operated from off to on, and less so when moved from on to off. I hear the click when the key is energized...
Using the choke may allow the engine to pull fuel past the pintle valve, or you might have plugged passages as noted.
tom