Thanks for the info, i need to get some sort of small vac. I know the diaphagm was stiff and warped with a small hole in it. all the gaskets were stuck and hard on the body parts. Took the L and H screws out and cleaned them they looked good, just waiting on the rebuild kit now.
Walbro Carb
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Sam R
8mm Socket
Yeah sounds like it's been sitting awhile. If the rebuild kit doesn't set you back much you can try it; but if it's something you'll be doing again; good idea to check those little check valves and such first because they can't really be replaced. Well I say that, maybe someone has figured out a way but for a $20 carb, is it worth it?
The kit was 4$ so I’ll give it a try. But went to my local Lowe’s to get a spark plug for my mower and they had a poulan pro 42cc with 18 in bar for 60$. It was a leftover model from 2018 that they found a pallet of and clearanced out to get rid of. So needles to say it can hone with me. 63$ with tax. Now this saw may just get fixed and sold.
Sam R
8mm Socket
If you goose the throttle will it keep running or does that have no effect? Might just need some tuning, too - did you turn the adjustment screws at all?
If you goose the throttle it does nothing dies immediately either way. I turned the adjustment screws in and then back out 1.5 turns, and the main idle screw is 4 turns out. It seems as though as soon as the gas in the carb is burned off it dies almost like its starving for fuel. The fuel filter and line is new. SO...
Sam R
8mm Socket
try coming out another 1/4 turn at a time on the L screw, see if you can't get it at least to idle.
Sam R
8mm Socket
Someone made a pretty good post about how to tune a diaphragm carburetor on this forum. Pretty solid details.
Basically I start out by setting the H/L screws to (in your case, what will run on L and H turn to 1 - 1 1/2 out from gently seated), turning the idle to about 500 RPM over what the book says it needs to be, then find the lean drop off on the L screw (there's more to it than this but this is the gist) and then turn the idle back to 500 over, then use the L screw to bring the idle back down to where it should be. Should give you nice crisp throttle response and then just dial your H in to whatever speed it needs to be probably 11-13k for that saw.
Basically as long as you don't have a fault in your carb, no air leak, good clean filters & plug this setup shouldn't give you any problems - also be sure and use good quality gas & 2 cyl oil.
Sam R
8mm Socket
Oh and make sure you make adjustments once the saw is warmed up.
Sam R
8mm Socket
The idle is a mechanical screw that just slightly opens or closes the throttle butterfly - it's possible it's turned so far out that it's not making contact; or if idle speed doesn't change w/ idle adjustment then you might be getting secondary air from somewhere (such as a bad throttle shaft).
Sam R
8mm Socket
But I'd check to make sure the idle screw is in far enough that it's actually moving the throttle plate.
Sam R
8mm Socket
If that's the case then your carburetor is junk.
Looking at the photos closely, it looks like your throttle lever plate is all messed up...like it's been ground off or modded in some way....also rusty and a mess. I, like Sam R, think it might be best to get a new carburetor.
Sam R
8mm Socket
Shoot, didn't even realize he'd put up pictures ages ago. Yeah, I would feel safe in saying that carb is probably toast.
