Chainsaw Overheating FIX

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user 188242

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Hello everyone, I recently patented a simple easy mod to keep those husky’s running cooler (no more hot start issue) cooler intake temps and cooler cylinder temps also allowing the air to dissipate out from under the top cover! Give it a look!
 
Depending on placement it is proven to lower temps! The pictures are for reference, you can place the vents anywhere in the top cover! Thanks for the feedback
 
Hello, I’m currently working with a company on a hydrophobic overlay to make these vents waterproof! There will be videos as well coming soon on placement and temp differences!
 
I highly doubt that would make any measurable difference to cylinder temps.
It will probably also lower performance as it will vent the positive intake pressure created by the Husqvarna air injection system
The air injection system doesn't generate positive pressure inside the air box. What it does is it uses centrifugal force to expell particles to away from where the air box draws suction. The air box still operates at a slight vacuum.
 
Everyone I know that uses stuff like that, use Frogzskin and not for purposes you say of running cooler either. https://frogzskin.com/

https://frogzskin.com/product-category/universals-mesh/
Just peel and stick on. The Frogzskin Mesh repels water, dirt, dust, etc. while still allowing air to flow freely. The Frogzskin Mesh is a woven polyester material and is HYDROPHOBIC, meaning it will repel water and splashes of water, but it is NOT waterproof.

fss.jpg
 
The air injection system doesn't generate positive pressure inside the air box. What it does is it uses centrifugal force to expell particles to away from where the air box draws suction. The air box still operates at a slight vacuum.
I agree the primary function is to separate debris out of intake air, but I believe it also increases intake air pressure... in my experience when a 3 series Husky saw is tuned with the top cover off, subsequent fitting of the cover will raise max rpm.
Probably why Jonsered labelled the feature as "Turbo"
 
Lots of these on ebay:
s-l500.jpg

I put them on some of my Turbo Clean saws a couple of years ago - they had been laying around at work for years, no idea where they came from.

@Nicholas_Cappadona is correct in that the Turbo Clean system has a hot start problem, because there is a connection from the hot flywheel @ cylinder to the airbox. It's fine while running, but at hot soak with the saw off the fuel will boil (vapor lock). E10 is worse in that regard, as are winter blend fuels.

Turbo Clean does not pressurize the airbox. The scoop isn't shaped properly for that, and you can't boost a 2-stroke without some sort of exhaust valve anyway.
 
I highly doubt that would make any measurable difference to cylinder temps.
It will probably also lower performance as it will vent the positive intake pressure created by the Husqvarna air injection system
 
Seems like top shrouds are designed for air flow around the cylinder and air filter to maximize cooling and air feed to the intake.
Take the shroud off the radiator in a car or truck and see the difference.
Sometimes extra holes aren't always the answer.
Ran into this putting pods on a GS750 motorcycle. Runs better with the stock intake.
 
Seems like top shrouds are designed for air flow around the cylinder and air filter to maximize cooling and air feed to the intake.
Take the shroud off the radiator in a car or truck and see the difference.
Sometimes extra holes aren't always the answer.
Ran into this putting pods on a GS750 motorcycle. Runs better with the stock intake.
I know with out them they run real hot.
 
I looked closer at how intake on my old Husq 288 and 266 saws seem to be designed. Fascinating...

Flywheel turns, centrifugal fan, as mentioned before. I think this DOES create positive pressure on the side of the engine because the fan is offset with a larger gap on one side than the other between fins and housing, how a typical centrifugal fan works. I think it forces air up and under the front section of the cover. This fan pulls in air from around the pull start cover and flows it up and over the cooling fins and out over the muffler toward the front.

However, there is also a divider under the cover which essentially seals, separating this forward section from the carb and air filter, which are located under the cover in the rear.

BUT - there is also a small hole or opening on my saws in the divider near the bottom. This is obviously where air enters the rear chamber for filtration. I think the hole is low to keep the intake air as cool as possible. If the hole were at the top, more heat would come in from the cylinder.

Also, dirt and dust and sawdust particles and chunks blow past this hole from below at high velocity due to the fan. The larger chunks have too much velocity to make the turn and go into the hole so therefore they fly on past the intake hole, keeping the rear intake region around the carb cleaner.

It stands to reason if positive pressure exists near the fan on the forward side of the top cover divider, then this pressure helps force air through the hole on it's way to the carb. It may actually help with air flow to the carburetor. I know the carb works on vacuum, but pressure on air on it's way to the carb may assist with intake and reduce the suction required to get the air in.

Mods:

By placing holes in the rear chamber where the carb is, the carb will suck air from atmosphere without the extra help of the force-feed from under the front portion of the cover. But, the air will likely come in a few degrees cooler, so maybe it's a wash?

Also, my saw has another hole with a plug, I think for snow operation, which pulls in more heat from the top of the cylinder. Remove this and get more air, and more dirt I guess?

Also, if the normal intake hole in the divider is enlarged, or more intake holes added, it seems this may allow the carb to breathe easier, BUT it also seems to me it would serve to circulate more flying debris and dust around the carb. If the divider hole is too large, I can see circulating more air around the carb than the engine can draw in, which would just add more dirt to the filter and around all the carb linkages.

It's got me thinkin'.

Overheating is more likely due to lean mix or overworking the saw under high load with low RPM, right?
 
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