echo pb-500 backpack blower bogs at full throttle

[ri chevy]

OK Just to Clarify here...
The H screw is on air filter side (Left when looking at the carb adjustment screws) and the L screw is on the engine side (Right when looking at carb adjustment screws)?
Thanks.

 

[SEAM]

"L" is usually near the throttle butterfly (engine side) and "H" near the choke butterfly (air filter side) on regular carburetors. On rotary carburetors this rule may not apply and on the WLA-1 there should be only 1 screw for idle adjustment, though.

 

[JONSSTIHL]

well, Sorry to revive a old thread but this problem keeps coming up. Every time I have had this problem a carb adjustment has cured it until the next season. I just replaced the spark plug and will try and tune it. I noticed the idle is a little low but still within spec.

Any ideas why the H screws seems to have no effect. atleast not with small adjustments I'm used to chain saws where 1/8 turn makes a big difference and this blower seems like 1/2 turn makes no change on the TACH.

 

[SEAM]

At high speed blower engines run under full load, making the adjustment less perceivable. This also implies that the engine is easily adjusted too lean without noticing. A lot of blowers are killed that way...

 

[mountainlake]

I adjust the high on my blowers holding the throttle wide open and then for max rpm. To lean or too rich they slow down. Steve

 

[SEAM]

Leaning out during operation may also be a sign of a clogging fuel filter...