Echo PB-9010T Carburetor

[Merkava_4]

There's only one mixture needle in the image (7) I assume for the high speed circuit. Do you think maybe there's a low speed mixture needle that's not shown?

[bgsengine]

yes, it is integrated in the rotary valve (throttle) and requires a special d-shape screwdriver (maybe 2 or 3mm diameter, if that)

[Merkava_4]

bgsengine - Do you think the mixture needle is down in that smaller hole that's in front of the larger hole that (5) drops into?

[KE4AVB]

Yes.

[bgsengine]

Yep. on Echo, that hole is typically sealed with the little black limiter cap, the adjustment screw is underneath. On the carburetors that have them, that's where the low speed mixture adjustment is. Most all Echo are fully adjustable carburetors, low end consumer models typically are fixed jet , it is quite rare to have to adjust the low speed mixture on those, however, and the adjustments crews do not adjust like most others, they have wider range of turns out. MOre common problem where that rotary valve is involved, is when someone damages that *very thin* o-ring seal that seals valve into carb nody, and/or loses the roller (that ramps open the valve- if you hold valve wide open, the round portion of the valve should line up all around with carb body, if it does not, the roller (barely 2mm diameter - very tiny) is likely missing. very easy to lose those tiny rollers if you are not aware they are there, when you go to pop carburetor apart and remove rotary valve.