How many of you use your 990 for throwing snow? I've had quite a few trials and tribulations in this endeavor. When she's runnin good it does some serious work!
I'll share some things I've experienced and learned.
I had a no spark issue and after going thru the generals (checking connections, new plug correctly gapped, checking points/gap, etc.) I began to suspect the magneto. On account of when I checked the points, there was a fair amount of frost under the cover. Dealing with temps down to -40 here in MN and a non heated non insulated garage. A hot engine turned off in sub zero temps is going to make some frost.
I looked at what was involved in accessing the magneto and just decided to put a tank heater on the cover over where the magneto is. Left it on overnight and Whammy! She fired up.
Also adjusted the carb settings. Do any of you adjust for summer vs. winter? Curious if that is an actual issue. It was bogging under heavy load, and even back fired a couple times. I have the idle set at 2 turns, the other at 1 3/4 or so.
I also have found that I barely need full choke for it to start. I use full choke to get her to pop, then low (1/4 choke), then no choke all within 20 seconds or so to get it started up.
After blowing snow I find snow/frost in the air filter, the hose that comes into carb, and down the carb throat beneath where the air filter resides. Sorry but I don't have the lingo to describe better. I hit this with carb cleaner after blowing snow. Also carb cleaner to moving parts of carb (idle mechanism and setting screws). I make sure the air filter and cover are clear of frost and dried. It's a bit of a hassle when I want to get in the house next to the wood stove and dog and a beer, but sets me up for success when the snow flies again. And believe me we have had LOTS of snow this winter in northern MN.
Here's some pics to clarify. You can see the frost down in the throat of carb.
Drying the air filter and cover.
Location of tank heater to thaw magneto.
Defrosted idle mechanism, etc after a hit of carb cleaner.
The beast after her chore.
Any more info, comments, or similar "tricks" appreciated.