Compensated carburators, What does it do?

[Stevo Bambino]

I have a 034 without a compensated carb and I think it needs a new carb. I cleaned it and rebuilt it and it still does not work quite right. I think there must be some corrosion or blockage in the low speed orfice where I cannot get at it. I also have a 036 which does have a compensated carb. That carb seens to need some work also, but I just got the saw and have not had time to go through it yet. I was thinking it would be nice if I only had to buy 1 type of air filter that could be used between both saws. I could delete the compensation part on the 036 by putting a different cover on the carb. Or vice versa to the 034. But, I am not sure what the compensation part does and if it is important or not, or if there is more than just the carb that is different between the saws. Any info and/or experience is welcome.

 

[Maintenance supervisor]

Its supposed to react to the air filter being dirty, keep your air filter clear and swap away.

 

[Stevo Bambino]

Well that is easy. I already keep a very soft cheap paint brush in my saw box so that I can brush off the air filter every time I put fuel in the saw. IDK if that is good for the air filter but it always bugs me seeing a filter full of sawdust.

 

[mbrick]

Well that is easy. I already keep a very soft cheap paint brush in my saw box so that I can brush off the air filter every time I put fuel in the saw. IDK if that is good for the air filter but it always bugs me seeing a filter full of sawdust.

A filter full of sawdust bothers me too, so I run Huskys

 

[J D]

The compensated carb vents the back side of the metering diaphragm to the inside of the air filter rather than to atmosphere. So, if the air filter clogs up reducing air flow it will also cause more of a vacuum to develop on the inside of the air filter which in turn sucks the metering diaphragm back slightly which in turn reduces fuel delivery slightly.
Some carb/saw designs implement this better than others, on those that have issues a common fix is to convert them back to uncompensated

 

[Maintenance supervisor]

Well that is easy. I already keep a very soft cheap paint brush in my saw box so that I can brush off the air filter every time I put fuel in the saw. IDK if that is good for the air filter but it always bugs me seeing a filter full of sawdust.

A simple solution is to get a prefilter from Outerwears in Pennsylvania. You'll never need the brush again.

 

[Stevo Bambino]

Would you recommend aftermarket carbs or should I stick with oem? The oem carbs are very expensive.

 

[3000 FPS]

It sounds to me if you keep the air filter clean then no big deal.

 

[Maintenance supervisor]

I always buy oem carbs cheap and rebuild them, but have had decent luck with aftermarket carbs.

 

[C George]

Not a great system ,, do your maintenance and get a saw wo it !