gets really hot!

[ghitch75]

i have an old homelite super xl(yes you'll say it's junk..but i like it) and it get so hot that it boils the gas in the tank and i have took it part and cleaned it up like it was new....and as far running it will eat ass till it gets hot...i tryed riching the carb and that helped a little....anyone have any ideas on this?.....thanks

 

[Lawn Masters]

Try cleaning the cooling fins on the cylinder, and clean any dirt inside the engine area, sawdust, dirt, dust, grime whatever. If its not metal plastic or rubber and not supposed to be there out it goes.

I'm just guessing that theres alot of dirt in the engine area acting as an insulator and keeping the heat in, which is boiling the fuel in the gas tank.

Just my opinion on this.

 

[Lewis Brander]

Running HOT.

I would say that if you had an operator's manuel I'd check to see if it described how to set the igniton timing. If it's adjustable, I'd say the ignition or magneto timing is to retarded, assuming you throughly cleaned the saw. Also she might be sucking air and running lean or the carb adjustments are too lean. JMO. Lewis.

 

[Chris J.]

No first hand experience, but

I know that I've read some posts/threads here that discuss certain makes & models of saws that boil the gas. Try a search for boiling, boils, boil, etc.

 

[Newfie]

Plugged tank vent could be causing a vapor lock which would lead to the fuel "boiling". Or so I've heard tell.

 

[Crofter]

Not sure how the Super XL compares to Super Mini I had but on that the Carb is pretty burried in metal and there is a lot of heat transfer into the fuel tank. No rubber isolators there. Any time I used it for any length of time was cold weather so cant remember having vapour lock problems. It later wound up on a large Radio controlled plane but vibration was bad. No vapour lock there!
I wonder if those old designs of saw are more prone to vapour lock with the modern fuel formulations. Point gap will influence timing somewhat and could have an effect on heating. I would be more inclined to suspect carb or tank venting. The following thread might have something in it.



http://www.arboristsite.com/showthread.php?s=&threadid=13450&highlight=PP+295

 

[ghitch75]

the saw is clean..i took it apart the first time it did it blew it out with 135psi air and the vent cap is working(will let air in but not out...this is how it should work if not gas would spill out when you turn it side ways) i richin' the carb out to the point it would burn your eyes when it runnin'....when it dies there it still about a half of a tank of gas in it and when you loosen the cap gas will spray a foot out around the saw!!!!...btw these has been on days when the temp is 85 or above it didn't do it last summer.....i'll pull the flywheel and check the points....but it sure runs good till it gets hot!!!

 

[Fish]

remove the muffler and look at the piston before you spend too
much time on it.

 

[ghitch75]

hey fish what i'm i looking for?...is it cracked, rings stuck,burn't?....

 

[Fish]

Yes.
When someone brings in a saw with a saw that gets hot
after using it a while, I always look at the piston first.

It is usually bad news.

 

[ghitch75]

ok i looked at the piston and there are just a few scratchs on it don't look that bad to me..i'v seen alot worst..should i pull the cylinder off to see what is on the other side?

 

[Fish]

Have you checked the fuel line? If it dies at about 1/2 a
tank, and the saw gets too hot, the fuel line might just be the
problem.

 

[ghitch75]

ok i ran a full tank through it yesterday...temp out side was 67 and i have a inferred thermometer and the head temp was 276 after the full tank on the day it boiled the gas it was 90 outside and the head temp was 426 ..so i guess it was just the heat that day?....but other saws i have don't get that hot on hot days..i guess it's just a cool day saw...the fuel line seems fine..and when i mean it was boiling the fuel i mean it was boiling!!!!!!...even after i got the gas cap off(after it blew fuel everywhere!) and you could look down in it and it was still bubbing!!!.....

 

[techdave]

ghitch, is the fuel you are using from the same source as the fuel used lst year? Both temperature and vibration tend to make fuel develop bubbles. Increased vibration like from a dull chain or worn drive parts or a scored cyclinder will cause oxygenated fuel to develop bubbles. Too many bubbles make for lean running, and will raise the temp even more, making for a vicious cycle. Not likely but I have seen it happen. hTH Dave.

 

[Crofter]

Techdave.

Interesting the bit on vibration. In RC model planes it is often necessary to cushion fuel tanks in foam. you can watch the foaming of fuel as you rev up. Unbalanced props, hard mounts etc. make a difference. Some fuels are more resistant. The bubbles lead to lean running / heat. Might have some parallel to this saw. I know my old homelight would numb my fingers in short order. Could this particular saw have a higher vibration level for some reason?

 

[Dadatwins]

All of the old homelite xl-12 that I had would always boil gas in the tank while running. Since the metal gas tank was bolted to the metal crankcase and head without any anti vibe the heat just traveled. Of course the more it ran the hotter the motor and more boiling. Had to always take the gas cap off slow or get a gas bath. Always thought this was normal design flaw in those saws.
As for vapor lock, keep cap vent clean and try adding some extra oil to mix. Be careful not to idle saw that much if you run extra oil mix it may foul out but will be ok at full speed.
Those old saws were tanks but sooo heavy in a tree.

 

[ghitch75]

thanks for all the replys i guess it will be a cold weather saw from now on...i reaaly hate to tear it down because it still cuts like hell!!!....so i guess a wait for it to die all together...thanks again