Boiling Gas?

[chipsfly09]

A friend of mine changed saw brands because he said that his was boiling the gas-- I have heard of this   never seen or experienced it-- he said he was running the saw hard-- it shut off- he opened the tank to see if it was out of fuel-- looked in and the fuel was "boiling like a wiches cauldron".   I have not researched boiling point of gasoline-oil mix. Perhaps this was due to tank temp. Is it possible that it could have been a result of a vac in the tank-- which should have relieved when the cap was removed-- Perhaps the saw was hot enough to vapor lock ??  Maybe this is common in some saws?  Any thoughts?  May have been discussed here before ad nausium-- forgive me if that is the case-- relatively new here-- Have really enjoyed info here so far.. Don't want to knock a particular saw brand-- that's why I did not give make and model-- It seems that all saws are loved by someone--especially here--I like that!

Thanks

[Al_Smith]

 It used to common on the old Homelites .I've never seen it on a modern saw .

[mike_van]

Tearing one apart & really cleaning the fins, etc. of all the oily chips will usually cure overheating.

[Ironmower]

Hey my ole' Homelite super XL would do this. Al Smith is right clean the fins and make sure your not runnin' it to "lean". Careful I got a face full of boilin' mix one time, not very pleasant. :(

[John Mc]

If your muffler is a catalytic one, switching to a non-catalytic muffler will also help a saw run significantly cooler. It made a big difference on my Jonsered 2152.

[Al_Smith]

 I think it has more to do with the saw design more that anything .

Older horizontal cylinder engines with the tank over the cylinder seemed to be the worst for boiling .

I had an s-25 Poulan  do it once but that was in the Colorado mountains at around 10,000 feet elevation on a deer hunting trip . The saw ran ran fine though after being adjusted for altitude . Didn't miss a beat .