I hesitate to explain my mower problem because the experts have such quick and certain solutions, and I really think I have ruled out a carburetor issue. I don't pretend to be a small engine maven myself, but I have had to become somewhat knowledgeable just in self-defense. The mower is a Honda Harmony HRR216TDA, which has given me no trouble for five years.

I will admit that this year, after hauling it out of storage, I changed the oil and filter. I had run it dry last fall and put new gas in it this year, and put in a nice new E-3 spark plug. It ran fine. The next week I took the Quadra blade(s) off and sharpened them. But I turned the mower over the wrong way, and after it wouldn't start, I took the paper air filter cover off and found that it was partially soaked with oil/gas. After letting the mower sit for a day, I changed the spark plug (and bought a new filter) and after a few pulls the mower started but was blowing dark smoke from the muffler. It kept running, and after a few seconds I pulled the lever back from the choke position, and then the smoke began to clear. But then the idle started to slow and I needed to return the lever to the choke position to keep it running. And that is how it has been since. It starts fine with the choke on but won't run with the choke completely off or completely on. There is a spot where it will idle, but not fast enough to engage the self-propelled mode or actually mow.

When I called a Honda repair place I was told I needed a new carburetor, and that the repair would take weeks to complete. I decided to learn how to do this myself, and I ordered a new carb from Plano Power Equipment. When the carburetor arrived I realized that I hadn't ordered the gaskets, and so I went over to a local repair shop and they had all the gaskets (but didn't stock the carb, so it was fine that I ordered the carb from Plano).

With the new carb (and gaskets) installed the mower runs exactly the same. If I spray carb cleaner around the outside of the carb to check for air leaks, it makes no difference. If I spray carb cleaner into the air intake, the motor stumbles, then recovers.

Next, I took the main jet out of the old carb and cleaned it with carb cleaner. Holding the jet up to a light source shows all the jet holes clean and open (even the litle ones). I took the main jet out of the new carb and cleaned that too. I replaced the new jet with the old jet. I switched back to the old carb. I checked the fuel lines. I checked the fuel shut-off valve. I took out the float pin and checked the float and float valve (on both carbs). Fuel flows nicely when the float is down, and the float shuts off and stops when lifted up.

The mower starts easily with one pull, but will not stay running with the choke completely on or off, and the mower won't increase to a normal speed. I can play with the choke and the throttle plate lever and get it to think about running faster, but it just seems not to be getting enough fuel. So, yes, it would seem that that jets are gummed or the float needle valve is not working, but having the same symptoms with two different carbs (and cleaning and interchanging the parts) makes that unlikely to me.

Instead of continuing to borrow a mower, I bought a cheap mower with a Briggs, and that works fine. But I still have this obsession to fix the Honda, especially since I now can get a carb off and back on in just a few minutes. I would like to be able to find the problem and fix this too. Any ideas?