Poulan overheat work around?

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MattFL

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I've got a couple of Poulan 40-something cc 18" saws that I've had for a number of years. For light duty use they run well and cut fine, but for major cutting they both will overheat and quit until they cool off. For example, we had to remove a large cedar tree and after several minutes of full throttle cutting they act as if they're running very lean, and if you don't keep them revving they will stall and refuse to restart until they have cooled down. Then once cool they start and run fine again, and the process repeats. This makes for a very long day. I'm in S. Florida, ambient temps are typically in the 80's and 90's. I'm not sure if the fuel is boiling or if it's electrical, but both saws do it so I'm guessing it's a characteristic of the design. Does anyone know what is actually happening, or if there is a modification or fix? I've recently acquired a Stihl that I'm hoping won't have this problem (haven't used it yet), but these saws cut fine for occasional use so it would be nice to get them working more reliably. :)
 
Thanks for the replies. The caps are venting, I've tried removing them when they stop running but it doesn't help. Pumping the primer bulb gives fuel flow but does not help get them going. If I put a fan in front of it the time until it runs again is drastically reduced. Also if I can somehow keep it running for a few minutes without stalling and without load then it will eventually cool by its own fan and start running fairly normal again, but it takes several minutes of no load running. If it stalls or you shut it off, you're screwed until it cools. They are clean, I've had them both apart.

One is Poulan model 1950LE, the other is Craftsman branded but otherwise identical, model# 358.360280. The Poulan part# indicates 33cc, but it is definitely a 42cc motor identical to the Craftsman. Just like this guys saw, I think Poulan must advertise different motors for price point, but actually use the same motor to reduce manufacturing cost.
 
Try turning the high side needle out an 1/8 of a turn to add a little fuel. Saws will lean out some in a long hard cut.
 
If your saw has the splines carb screws these crimp connectors work great for adjusting them if you don't want to buy the tool.20180717_161335.jpg
 
They are tuned a bit on the fat side, any richer and they won't rev out, but I'll try turning it even richer next time they quit to see if that helps with a restart. The choke does not help with a restart. If all I'm doing is small cuts then the saws will run the whole tank without problems, and will stop and restart easily; it's only if they're being worked hard that they quit.

I use one of these tools from eBay to adjust the carburetors, they work great.
 
You want a professional grade chain if you don't already have one. The depth rakers are easier to maintain allowing the chain to keep enough load on the saw to run a safer temperature.

If the chain is dull or rakers are too high the cutter cannot bite enough wood to keep a load on the saw. Keeping a load on the saw will help it run at a safer temperature.
 
Matt , the LE muffler has a small 1/4" outlet under the louver plate and spark arrestor screen . Trying to exhaust a 2.6 cubic inch engine through this small outlet is the heat bottle neck problem .
Are the mufflers crimped or pull apart? There pretty easy to open up if there pull apart.
 

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Matt , the LE muffler has a small 1/4" outlet under the louver plate and spark arrestor screen . Trying to exhaust a 2.6 cubic inch engine through this small outlet is the heat bottle neck problem .
This^^^. Do what you gotta do to open the muffler up a bit, retune, and these saws become a lot more user friendly.
 
I have several of the 42cc poulans. A muff mod makes them run 100% better and way cooler. Ive had the carbs oveeheat ant the coils overheat and lose spark while hot. Muff mod helps both problems. I have a heavily modded 3314 that had every problem knowen to them. I trimmed the cover modded muff modded stratos ported welded a popup piston and the whole deal. That saw is silly for 42 ccs.
 
Might be worthwhile to check pressure/vacuum on the saw, an air leak would cause lean/hot condition.
 
I saw a solid 100 degree temp drom on my cylinder by nodding the muffler. Before modding it i was seeing consistant 400-450* cylinder temp right next to the spark plug. Also the coil was getting to 300* on the laminations after several long 2 min cuts. I assume that heat was causing my coil to kill spark. After the modd my coil never gets above 200 in the same situations. Ive never had another single mod nake such a drastic improvement to the power and usability of any other piece of equipment. Im sure my carb saw similar temp drops after muff mod also.
 
Wow interesting that they would produce a saw with this problem when the potential fix, or at least improvement, is so easy (punch a bigger hole). There must be some other reason they kept the hole small, maybe emissions or sound. I've got to get the proper torx driver to get the muffler off and then I'll give this a try.
 

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