Originally Posted By: Nick R
I do think personally that lawnmowers have stagnated. I mean seriously, they pollute worse than any car engine out there these days, due to lack of cat, and emission control. They are extremely inefficient, with carbeurator, most with L-head engines.
I mean, it can't be that expensive to at least make an OHV engine, with basic electronic fuel injection, and a small cat. Eh, pipe dream probably.
That's why I like the newer B&S with walbro carbs: they simply get the F/A mixture right, much, much better than those older B&S with nylon carbs (pulsa-jet or similar).
After the mow, I took the spark plug off: I saw whittish powder on the electrodes similar to that on an automobile engine. This means that the engine is capable of reaching (then maintaining) a pretty decent combustion chamber temperature and is fed with proper F&A ratio.
Compared to all my other B&S, including that B&S quattro engine that I religiously maintained: electrode has always been a bit black but always run (indicating F&A runs richer than I thought) on them no matter how hard I tried to get the F&A right.
Of course: on the other hand: all the Honda engines I maintained are running in optimum F&A ratio fashion, citing that I can use automobile platinum plugs ( I have NGKs left over), using more like a motorcycle carb (with manual hand choke for cold starts, as opposed to that rubber bulb on B&S that sez "press 3x" for cold starts, geesh!)
small engines and engine manufacturers can do more (I know) but somehow, they opt for their profit bottomline and choose to use the cheepest way possible to get by. Adding all tons of add-ons such as PCV, cat convertor, etc. will call for more $$, which, somehow the domestic dominant player (builder) such as B&S would try not to play with, for Chonda and the likes has got on to the local small engine markets with all sorts of cheep, highly competitive pricing stuff even for chonda clones (which can be had for less than 100 USD, try that with B&S and you'll see what I mean).
Q.