Being the neighborhood OPE fix-it guy, I get the opportunity to be stymied by a wide variety of problems. The most recent was diagnosing a Honda FG110 tiller. Now this isn't a chainsaw of course, and it's not even a two-stroke, but it still uses a Walbro diaphragm metering carb. Symptoms were that the unit would start, but would only run at high speeds--and not very well at that. Unit would sometimes idle but not well. Anything in between idle and full throttle was impossible. And it got progressively worse the longer it ran.
I disassembled the carb and everything was clean. It is the simplest of carbs--no H or L screws to adjust, just the idle screw. I looked up the carb IPL online to make sure the gaskets and diaphragms were located correctly and they were. The only thing that really caused me any concern was that both diaphragms were a little hard and stiff. I used the "soak them in DOT3 brake fluid trick" that I learned here and was pleased to see how soft and pliable it made them. I had never tried that before but I'm hard pressed not to believe that E10 gasoline won't make them hard again in short order. Does the DOT3 brake fluid trick really last very long?
Put everything back together and no change. Disassembled everything again and had my 14 y.o. look closely at the diaphragms. He could see a couple of small pinholes in the metering diaphragm, right near the edge, that I couldn't see. I had to use a magnifying glass and hold the diaphragm up to a bright window in order to see them. Bought a carb repair kit from bigvalleymower on ebay and all is good again.
I wouldn't give up all I've learned at 47 to go back to being 27, but there are some days that I really miss having good eyes.
I disassembled the carb and everything was clean. It is the simplest of carbs--no H or L screws to adjust, just the idle screw. I looked up the carb IPL online to make sure the gaskets and diaphragms were located correctly and they were. The only thing that really caused me any concern was that both diaphragms were a little hard and stiff. I used the "soak them in DOT3 brake fluid trick" that I learned here and was pleased to see how soft and pliable it made them. I had never tried that before but I'm hard pressed not to believe that E10 gasoline won't make them hard again in short order. Does the DOT3 brake fluid trick really last very long?
Put everything back together and no change. Disassembled everything again and had my 14 y.o. look closely at the diaphragms. He could see a couple of small pinholes in the metering diaphragm, right near the edge, that I couldn't see. I had to use a magnifying glass and hold the diaphragm up to a bright window in order to see them. Bought a carb repair kit from bigvalleymower on ebay and all is good again.
I wouldn't give up all I've learned at 47 to go back to being 27, but there are some days that I really miss having good eyes.
