So my lawnmower up and quit on me today. It's been hard to start for the last two years when the primer button or bulb quit resuming natural shape/position. It doesn't have a butterfly choke. Probably due to "emissions" reasons and people running them with the choke on. So, the "new" carbs have a primer instead, in an attempt to make the machine "smarter" than the people.
Anyway, to get the thing started I had resorted to removing the air filter and putting a knob into the intake to choke it. I'd use my hand, but the starter pull is way up by the push handle for the mower.
Anyway, after mowing a while the thing quit like it had run out of gas...but there was still about a third of a tank left. Pork.
So, I washed off the grime around the carb to find the bolts and screw heads, and took the carb apart.
Below is a picture of what the ethanol gas did to the rubber bulb/button primer. I've turned it inside out over one of the carb bolts to expose the inner side to the air. It does seem to be hardening, after an hour's exposure. But, there are holes in it now, and it can't be restored to proper operation.
You'll note the rubber has turned into a thick grease or putty. It's very sticky and what is coating my fingers.
There is also a large fiber reinforced "gasket" that goes in the join between tank and carb body as shown in the second picture. It has not dissolved as the rubber bulb did, rather it has hardened and become brittle. It was still sealing well enough, however there are two flapper valves that are part of the gasket. I believe those valves are used to pump the fuel up from the larger tank and fill a smaller reservoir on top of the tank for carb jet feed. Anyway, you might be able to see that one of those flappers is very hard and curled to the point where it won't seal anymore.
These seals, gaskets, and rubber parts weren't made for ethanol exposure and have failed due to its introduction into the common fuel supply. I suppose many would just throw the mower away and buy a new one with all the new sales tax going to the state, and umpteen middle men making profit and paying income taxes on it, paying "disposal fees", etc.
But, I'll figure a way to fix it and have it serve once more, as it is only those tiny parts that keep it from being useful. It's going to be tricky as the entire carb body is made of plastic that I'm sure carb cleaner will dissolve.
Thank you big corn, and the government, for making fail what would have taken 20 years to wear out with the proper fuel supply. I'll now be getting leaded gas from the airport for my mowers, as it is the only gas in California that doesn't have mandated ethanol blended with it. And yes, I know that it will be dumping lead into the air from my mowers for many years to come. But, the unleaded fuel from the local station is poison for my machines.
I posted here so that you will see the internal affects that ethanol has on older carbs parts. I feel certain the damage is not limited to only lawn mowers, by any machine made before the introduction of ethanol contamination into the fuel supply.
