Fuel boiling

[bryanr2]

Has anyone ever seen this? I was quartering some maple logs with my Johnsered 2095 and stopped it to clear the noodles from under the clutch cover and adjust the chain. Went ahead and checked the fuel while I had it off and the fuel was (for back of a better word) boiling in the tank. Is this common in saws with a metal fuel tank? Just wondering. Sorry to sound ignorant but I dont know the answer, and the words I used to try to search resulted in nothing.

thanks
Steven

 

[tlandrum]

ive seen it happen in a plastic tank too

 

[pastryguyhawaii]

Saw the same thing today with my 2094.

 

[Anthony_Va.]

I've heard of it happening but I've never personally seen it. Is there something wrong to cause that or what?

 

[emr454]

I've had it happen in my little Homelite super ez when I work it too hard trying to cut bigger wood than it can handle.

 

[bryanr2]

Well I wasnt in wood to big. The logs where chunked into 14'' sections for my wood stove, so I had over half the bar exposed. Is this something to be concerned with?

 

[BroncoRN]

Probably a pressurized tank and when you opened cap and changed pressure gas boiled. Or could be heat if it was a hot day and you ran saw hard. Just switch to back up saw and allow that one to cool a while.

 

[Oddvaark]

I have had similar problems also. Years ago . . . a friend told me of how he used to put diesel in his 2cycle mix to prevent that . I can't remember his ratio but he swore by it . I just did a search and if you go here, you can read something that you may find interesting.
I am somewhat (quite) computer illiterate so I can't cut and paste(?) like most of you can so just do a search here for ; "adding diesel to high ethanol gas" .
Hope this help and it should prove interesting to hear the results.

 

[Stihl-Pioneer]

I have seen it on the smaller p series Pioneer saws before.

 

[a. palmer jr.]

I have seen it on the smaller p series Pioneer saws before.

I think it happens more with metal tank saws, there's no way to isolate the heat from the tank. The upright cylinder saws with the tank built into the handle probably would isolate the heat from the fuel the best. Otherwise, like was written above, just shut it off for a while and use the backup until it cools down. This probably doesn't happen in cold weather when a lot of people cut their wood.

 

[MarylandGuy]

Pro motocross riders have issues with fuel boiling from time to time. When it happens, enough fuel can boil out of the overflow hose to a point where a rider runs out of fuel before the end of the race.

Of course their tanks are hand made aluminum and it only happens on very hot days.

To combat it, the teams store the fuel in coolers with ice and gas up right before the race starts.

 

[bryanr2]

Pro motocross riders have issues with fuel boiling from time to time. When it happens, enough fuel can boil out of the overflow hose to a point where a rider runs out of fuel before the end of the race.

Of course their tanks are hand made aluminum and it only happens on very hot days.

To combat it, the teams store the fuel in coolers with ice and gas up right before the race starts.

thats interesting. when i removed the clutch cover to clean the noodles there was some fuel dripping down the case of the saw from a hose (looks like a tank vent) there is a hose that comes down thru that smallest square recessed area.

 

[carym2a]

Homelite XL super auto, seen it happen a few times with the old gal on hot days doing lots of bucking.

 

[Zippy]

Vent?

I have seen it on my 242xpg that is also is prone to vapor lock.

I was wondering if a blocked tank vent could cause it - as the fuel is drawn out if the vent doesn't flow then the pressure in the tank drops which lowers the boiling point/makes vaporisation easier.

 

[fossil]

Found this. Something to consider.

Most gasoline has the boiling range of about 90°F - 430°F . You don't normally see it boil though, it typically just evaporates. However if you were using a gasoline you bought during the winter it is very possible. The gasoline changes by season, (summer and winter). Winter gasoline has a higher vapor pressure and contains much more light material such as butane and iso-butane. If you were using that in warmer weather it would boil very easily.
Source(s):
23+ years of gasoline laboratory testing

 

[Chris-PA]

Found this. Something to consider.

Most gasoline has the boiling range of about 90°F - 430°F . You don't normally see it boil though, it typically just evaporates. However if you were using a gasoline you bought during the winter it is very possible. The gasoline changes by season, (summer and winter). Winter gasoline has a higher vapor pressure and contains much more light material such as butane and iso-butane. If you were using that in warmer weather it would boil very easily.
Source(s):
23+ years of gasoline laboratory testing

That's an interesting point - I understand the east coast suppliers may be late switching over to summer blend this year, as there is a shortage of supply and they don't want to make it worse with the delays in switchover. Not sure what the situation is in Tennessee. Also, it's generally warmer than normal this year in most of North America.

 

[superwd6]

Old XL922 Homelite did it all summer long.Dad used to over fill the oil, then purposly over fill the gas to wash off the saw:msp_ohmy:. Can you believe that saw caught fire:hmm3grin2orange:

 

[bplust]

Whoa!

I've never experienced this, I live in a colder climate (Vermont), but something I thought of when I read through this thread was an ms260 I used to have. I pulled the muffler once to clean out carbon, and put it back on incorrectly and burnt a hole in my cylinder shroud. Never boiled my fuel, but those familiar with that saw know that there's no way that exhaust could get back to the tank enough to be the cause of boiling fuel.

Incorrectly assembled saw/ bad muffler gasket could be a problem depending on the saw. Just a thought.

 

[bryanr2]

it's new gas. I bought it at a Shell station that sells 93 octane non ethanol fuel. Could the non ethanol be a contributing factor?

 

[cbfarmall]

My Jonsered 81 did this today. I was checking the fuel tank, and didn't hear the hiss when I loosened the cap. Got the cap loose, pressure released and fuel blew up all over me and my truck. Saw the fuel that was still in the tank boiling. I've always heard of this, but its the first time I've seen it. Next time opened the cap, I did it slowly and with a rag covering it.

It was warm but not hot outside. I was ripping rounds for my uncle who wasn't able to handle them otherwise.

Chris B.