Anybody know anything about a 21 HP Briggs Vanguard 2 cylinder engine? My Troy-Built mower has one. A couple of years ago it started missing and lugging down under load, sometimes when I initially engage the PTO. I took it to a local mechanic a while back and he said it was carburetor. He rebuilt the carb and hit me for several $$. Later that year it started doing the same thing. I can pull the spark plugs and one of them will be covered with carbon but dry. Most times I can change that plug and it will run fine for a while.When it is missing out, it blows black smoke--not bad but noticeable.
I have ran regular gas, not the non-ethanol stuff, in it and have added Stabil and occasionally Seafoam to the gas. Each year I replace the fuel filter when I change the oil. I'm at a point that this is getting to me, having to deal with this most every time I use it. The mower is around 18 years old and has given me flawless service up until the time this started. It only takes me 45 minutes to mow my whole yard so it doesn't have nearly as many hours on it as most 18 year old mowers would. I might have to add oil to it once during the mowing season. Replacing it is not an option now.
I'm going to replace all of the fuel line from the tank to the carb with a new filter, change air cleaner, already put new plugs in last night. Any ideas?
