Summer heat and the 346XP

[pigwot]

Okay,
Been tuning my saws for 30+ years and sometimes they run just great for years and then this one decides to give me grief.
It's my newest 346XP - has run great for about 9 months with the usual maintenance, but now when it gets hot out (97* today, triple digits for the next three days projected) the ceramic vent on the gas tank leaks gas and it gets hard to start after it has run for half a takedown. And no matter how I try to adjust the carb, reclean the air filter, make sure the gas filter is clean, check that the impulse tube/gas line are not softening and kinking, it remains impossible to start. So I swear a bit, and go to my backup saw, and then as we are ready to head home from the job and the saw is nice and cool I'll pick it up and it fires right up and runs great.

What should I be looking for? Too new to be bad crank seals I'd think...(the bad crank is the guy running the saw when it gets tempramental).

 

[NeTree]

Are the cooling fins clean?

 

[pigwot]

Yep, very clean, do a full tear down and cleaning on a regular basis.
Air compressor gets a workout...

 

[NeTree]

Measure your fuel temp when it's running normal, and again when it acts up. Sounds almost like the fuel is vaporizing early.

 

[Monkeywithasaw]

i have the same problem here in arizona the only cure for me is to carry a extra large cooler to set the saw in half full of ice or put the fuel in in it to keep that cold and it helps

 

[SkwerI]

Vapor lock, caused by fuel evaporating in the tank.
Keep your saws (and fuel) in the shade when you're not using them.
Always use premium fuel. The tv experts will tell you it doesn't make any difference, but it does.
If your saw vapor locks, crack the gas cap to relieve the pressure. Then use the primer to purge the bubbles out of the system and restart.

 

[pigwot]

Thanks for the tips. Keeping it in the shade on a large takedown is a problem, as the farther through the tree I get the less shade there is...
I have cracked the fuel cap and yet didn't think of priming to purge the lines.
I'll try that next time, and see what happens.
My truck gets the cheap stuff, but I buy top grade fuel for the saws.

 

[PCTREE]

Skwerlito, every time Im ready to write you off as a bucket jockey you go and drop another sage piece of advice which leaves me wondering "who is this Zen saw master".....

 

[Thor's Hammer]

Brian is dead right. The great daddy of the 346, the 242xp was famous for vapour locking in hot weather.
And yes, petrol quality makes a difference. When we could still get it at the pumps here, I used always use '4 star' or 98 octane leaded fuel. It always used to be better for the saws


Brevity and smelling errors courtesy of iPhone using Tapatalk

 

[pigwot]

Ed, my all-time favorite saw to use in the trees was the 238xp, stronger than the 234sg and held up through a ton of abuse. I miss that old saw...
Guess I am going to get a cooler and a couple bags of ice.

 

[woodworkingboy]

I use premium in almost all of my saws, them being modded, but I do find that some stock saws run better on regular. Good information on vapor locking.

 

[Thor's Hammer]

Ed, my all-time favorite saw to use in the trees was the 238xp, stronger than the 234sg and held up through a ton of abuse. I miss that old saw...
Guess I am going to get a cooler and a couple bags of ice.

We still have a 238 somewhere. Probably a 234 aswell if I know my Dad!


Brevity and smelling errors courtesy of iPhone using Tapatalk

 

[wiley_p]

The 266 was a vapor locking whore as well. It's super fun when a spotfire gets going over the line and your saw wont fire up.

 

[Tree Reb]

Most of my old Huskys hated really hot weather.

My favourite was a 444se, great little saw but if it didn't start first or second pull it had to sit in the shade for a while.

 

[Al Smith]

On occasion the electronic ignition moduals rebel if they get over heated also .

Might sound funny but if you set the thing a tad rich it will run cooler because a rich gas mixture burns cooler .Old trick in WW2 by fighter pilots with a shot up war bird that was runnng hot was to pull the choke part way out .It got many of them back that would have most likely locked up on them .

 

[woodworkingboy]

Hot saws not starting can be a coil going bad as well.

 

[Tree Reb]

I've still got that 444, I must get it going again, haven't started it for a while. I got a muffler, just need a gasket.

Loosened the gas cap one day and it sprayed fuel like it was boiling. Other than not liking hot days it never failed, and it did some work.

 

[HolmenTree]

The 266 was a vapor locking whore as well. It's super fun when a spotfire gets going over the line and your saw wont fire up.

Yes the old 266's with the solid mounted carb to the cylinder with engine heat transfering to the carb through the 2 cylinder studs was a problem. Also the vibration would self turn out the H & L screws also. But for loggers in the cold climates the 266s ran perfect. You just had to carry a carb screwdriver in your pocket.
We had a saying up here in Manitoba in the 1970-80s.... Husqvarna good winter saw, Stihl good summer saw.

 

[Ed L]

If the saw has a catalytic muffler, get rid of it, order a muffler for an older 346xp. Those things create so much extra heat it ain't funny.

Ed

 

[Al Smith]

A fully baffled muffler creates heat for that matter but that's a different subject .

 

[top_notch]

Our 441 is acting up in the heat. Even if we keep it in the shade, and its been about 85 outside, the saw will start acting up after cutting for 20 minutes or so. Anybody else have problems with their 441?

 

[SkwerI]

Time to trim the limiter cap on the high end jet screw and richen up the carb slightly. And check your spark screen in the muffler to make sure it's not plugged (maybe open the outlet hole slightly for better breathing). These two minor adjustments should lower your operating temps and reduce heat related failure.

 

[NeTree]

Probably a stupid thought, but you DO have the baffle switched to summer, right?

Excellent post, Brian.

 

[MasterBlaster]

HuH?

 

[Al Smith]

Butch some of the newer saws are equipted with a deflecter that throws heat back on the carb so they run better at low temps .I don't own any that new myself ,kinda goes with out saying .