Vapor Locked My Saw

Ran about 1.5 gallons of gas through the 441 tonight and cut / noodled about 1/2 cord of maple. Some of the logs were upwards of 250 pounds. As it was night time, I could see my muffler glowing red and occasionally the saw would shut off and I had to let it rest for 15-30 minutes before it would restart. Next time out, I'm going to alternate every 2 tanks on the 441 with 1 tank time on the 290. I know the 290 isn't as powerful, but I have to give my go to a rest to cool off.

Curious whether anyone has run into this issue when running hard. I have a massive pile of noodles that have to be dealt with. They are yellowish white so not much good for mulch.

 

On one big log, I could have used a bit more horsepower. A 461 or 660 would have been nice.

 

I'd be alarmed if I saw that. Mufflers get hot of course, but glowing is probably over 500F. Are the flywheel area and cylinder head reasonably clean, and not packed with sawdust?

 

You have a problem.... Several things to check:

* Fuel mixture ratio
* Carb settings
* Timing (did flywheel move?)
* Cylinder cooling fins for crud

I would pull the muffler and check the P&C before running the saw again.

When you say vapor lock, do you mean it would not pull over?

 

Definately sounds like it may be running lean.

 

Running ultralight aircraft engines too lean… doesn't happen for long before they go quiet and cause severe sweating. Prolly chainsaws are no different?

 

I am running oil mix as suggested...one container to one gallon. Stihl synthetic. I was thinking the same thing about a ported muffler. Bigger holes allow exhaust gases to vent easier.

 

No crud anywhere on the saw. I keep it clean. Need to double check summer / winter setting. I never toyed with that before so it came as it did from the dealer in August.

 

Vapor Lock meaning saw won't restart until it cooled a bit. Engine did pull over...just didn't start.

 

Man, you aren't kidding. You'd better hope you can glide to that field/road nearby or hit the ballistic chute!!!

 

Red hot muffler normally means a dirty air filter and sometimes air intake around the saw is getting restricted.

 

Yes...the saw is 8 months old. Probably has seen 3 gallons of gas...maybe 4. I want to check the summer / winter setting, but a muffler mod is in order to help that muffler dissipate heat. I see the 390XP is sold with a dual port exahuast...probably for that reason.

 

It happened, thankfully just once, at 1500' above my home strip. As I recall, I not only started sweating, but I noticed I got really hot too…

We used to practice engine off landings all the time, and it had a happy ending… but I don't like surprises much.

 

Wow...that surely helps it breathe and exhaust hot gases.

I was in summer mode. Cheap plastic part. I overtightened it just now and cracked the plastic although it still works. That was soft plastic and should have been hard plastic at the least. Metal preferable. Charge me $25 more and get rid of all the plastic bits...I will pay for quality. Ridiculous.

I am eying a 390XP on ebay. That is tempting to have 88 cc for when you are in some big stuff.

 

100 cc's or go home...