EPA Carbs - interesting!?

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Four Paws

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I have had 2 experiences with Walbro HDA carbs that have been limiter capped equipped. Both times after removing the limiter caps and cranking the screws in until lightly seated, both times the H and L screws required 3 to 4 complete turns. This struck me as odd. Both times the saws ran strong and were near new....the adjustments were not to compensate for leaky seals or any other problem. Do the EPA carbs have a finer adjustment? Maybe one of you guys knows the answer as to why they are set up like this from the factory.

Josh
 
Typically EPA carbs have much finer threads than before, and usually a bypass jet that feeds up to 50% or more of the fuel needed at WOT, with the H screw suppling the rest. So even with the limiter cap removed you really need a tach to tell what is happening as adjustments are made.
 
what Stihl#1 said....

and... you can no longer relay on the "1 turn out". Some devices (even from stihl) are like 3.5 on H and 2.5 on L....:dizzy:
 
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