Do you use something to slosh out the reservoir when changing from dino to vegetable oil or vice versa?
I run at least one full tank through. The problem arises when letting the mix sit over a few weeks. And not every brand react in the same way, some react faster some slower. But if I switch I run at least a full tank through.
But as said the routine used saws can keep canola oil inside. If in doubt just go into your wife's kitchen and check out how often the oil get's racid over a year. Normaly it's no problem what so ever for a year or more. I might add that I ONLY use canola oil, have never tried out sun flower or other types. And I ALWAYS fill to the brim, to keep air level to a minimum.
And don't forget to keep the plastic oil bottle in a secure closing metal can! Why you ask? Because all types of rodents love the oil in winter time! They even try chewing threw chainsaw tanks if given the chance.
How do I avert it? I have a small paint roller that I treat outside wood with old engine oil. I just dab the saw a little around the cap area with the roller. That masks the canola pretty well that I have never had a problem since. I even use it on the plastic canola oil bottles lid.
And last, your MAJOR enemy on canola oil, is your dog! When he get's the taste, he can easily crack open the plastic lid and just loves to lick as much as he get's! At least his fur is nice and shiny...
A little swab with the old engine oil and no problem anymore.
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