Sudden Idling Issues After Cold Weather

Bendroctanus · Tuesday at 12:52 AM

I might be lazy for bot wanting to thresh through the archives.

Had it happen on an MS441 Magnum and an MS660 Magnum. Both have had the cylinder replaced in recent years (not sure if that’s pertinent). Haven’t changed fuel or anything. I feel as though I had them tuned well. The 441 might be a leak issue as it is losing compression or making a funny noise after a while. Thought replacing the jug would fix it. It ran all summer without issues. The 660 was also running fine, (like a badger as my Saw-Fathah used to say), and now idles high and then dies after awhile. Seems to be related to the cold snaps we’ve been having (Central Illinois) but not entirely sure.

Penny for anybody’s thoughts.

Brando CalPankian · Tuesday at 3:34 AM

Non-ethanol (sorry, first place to start).

Bendroctanus · Tuesday at 3:37 AM

No, I refuse to run any ethanol. Made that mistake a long time ago. I’ve been using alkalyte for a while, VP and Aspen.

evo · Tuesday at 4:36 AM

Define temps? Maybe flip the cold air intake thingy?
Other than that a carb tune and failing that I’d start looking at old/bad gas issues

Bendroctanus · Tuesday at 4:57 AM

Well mostly staying below freezing but we had a some snaps of single digits and negative wind chill. I didn’t necessarily run them too much during but the saws live in the saw box. It does seem to be acting like the tuning is out of whack or bad gas but alkalyte fuel has a shelf life of one to two years. I’ve never had a problem with it sitting for awhile. It’s just weird, everything was running fine before December and now I have two saws running weird. I tried adjusting the 441 but no dice.

Bart_ · Tuesday at 5:53 AM

Maybe something sealing less well in the cold? Older harder crank seals? vent/pressure line etc.. hardened carb diaphram harder in cold?

My well used 200T runs different in the cold, actually ms260 too. I switched crank seals on a br400 or 420 and it was like I put a new carb on it.