New carb setup question. Husqvarna 545 clearing saw.

[mudfly]

Can someone please explain what the second throttle body is for on this carb setup?



Comes with these funny air intake horns.



It was not tuned remotely close for 10 F degrees and i don’t want to burn it up. I couldn’t figure out what special screw driver I needed to use so I had to remove plastics to get a better look. Why can’t they just use the slotted screws?

 

[Marley5]

Those " horns " are for air and fuel.
Looks like a brand new saw and a professional grade saw.
What's the saw doing to make you think it's not tuned properly for cold weather ?
Do you want to lean it or richen it ?

 

[mudfly]

Those " horns " are for air and fuel.
Looks like a brand new saw and a professional grade saw.
What's the saw doing to make you think it's not tuned properly for cold weather ?
Do you want to lean it or richen it ?

It’s bogging off idle to the point it will die if I don’t feather the throttle, so something isn’t right there. If I can get it up on the top end it screams. So I’m thinking rich on bottom and lean on top. It is new, so I’d rather run it a little rich for the first few tanks anyway.

 

[huskihl]

It’s a Strato engine. Difficult to explain, but traditional two strokes purge the exhaust out with some of the next cycle’s fresh charge. Strato engines suck a layer of fresh air through the piston and on top of the next incoming transfer charge. They use that fresh air on top to purge exhaust rather than purge it with air/fuel. Less raw fuel will be blown out through the exhaust. In your case, that fresh air comes through that top butterfly

 

[Marley5]

Sounds like it's starving and needs more low jet, CCW until throttle response is obtained.
Gotta be honest though, never ran a saw or any other equipment in 10*, wow

 

[mudfly]

Sounds like it's starving and needs more low jet, CCW until throttle response is obtained.
Gotta be honest though, never ran a saw or any other equipment in 10*, wow

Going to be below zero this weekend. I’ve cut firewood in -20F. If you start getting cold, pick up the splitting maul and warm up. Not a big deal unless it’s windy.