mr.farmall
Active Member
- Joined
- Mar 13, 2014
- Threads
- 12
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- 65
Hello
I have a mower with a B&S 21.5 v twin 407777 0128 e1.
About a month ago it started to load up the engine, almost as if it were chocked, while cutting tall grass, spewing black smoke. I throttled it back and it when back to normal. finished cutting without further troubles. Since then it has loaded up at high throttle even without the blades being engaged. A couple weeks ago with only medium throttle every time it hits a somewhat heavier cutting load, the engine loads up again, but will always clear up when throttled back. But now it is to the point that I can only throttle it half way before it starts loosing power and spewing black smoke regardless of the blades engaged or not.
I have pulled the carburetor. the throttle and choke work easily and well. It's been cleaned with an ultrasonic jewelry cleaner in a mixture of "simple green" and water. It looks really nice,( didn't look so bad to begin with). blew out the passages with low pressure air. all looks well. The float works good, doesn't have any gas in the float and the rubber shut off seal looks great. The only thing I was able to see was the tiniest bit of debris in the bottom of the bowl next to the electric shut off valve.
I will put it back together tomorrow.
Spark plug was a little fouled with a little black soot on the electrode, but not much. I've cleaned it up and have a spare. Air cleaner is in good shape, almost new.
I hope cleaning the carburetor will help the situation, but many of you would have a better knowledge of what is happening.
Any suggestion would be helpful.
Thanks Rex
I have a mower with a B&S 21.5 v twin 407777 0128 e1.
About a month ago it started to load up the engine, almost as if it were chocked, while cutting tall grass, spewing black smoke. I throttled it back and it when back to normal. finished cutting without further troubles. Since then it has loaded up at high throttle even without the blades being engaged. A couple weeks ago with only medium throttle every time it hits a somewhat heavier cutting load, the engine loads up again, but will always clear up when throttled back. But now it is to the point that I can only throttle it half way before it starts loosing power and spewing black smoke regardless of the blades engaged or not.
I have pulled the carburetor. the throttle and choke work easily and well. It's been cleaned with an ultrasonic jewelry cleaner in a mixture of "simple green" and water. It looks really nice,( didn't look so bad to begin with). blew out the passages with low pressure air. all looks well. The float works good, doesn't have any gas in the float and the rubber shut off seal looks great. The only thing I was able to see was the tiniest bit of debris in the bottom of the bowl next to the electric shut off valve.
I will put it back together tomorrow.
Spark plug was a little fouled with a little black soot on the electrode, but not much. I've cleaned it up and have a spare. Air cleaner is in good shape, almost new.
I hope cleaning the carburetor will help the situation, but many of you would have a better knowledge of what is happening.
Any suggestion would be helpful.
Thanks Rex
