KostasVolos
ArboristSite Operative
These two "hacks" were done on the new models of MS170 & MS180 (2-mix ) with the oval shaped air intake.
Hack #1 : Contrary to common belief the fine particles find their way inside the carb,crankcase and combustion chamber ,not from the air filter sealing weaknesses but from the insert on the air intake snorkel.
If the air filter is removed it clearly becomes visible that the insert has two oval shaped fitting gaps against the snorkel.One at the dirty side of the filter and the other ,positioned exactly opposite,at the clean side.Due to vacuum fine particles find their way inside this non-sealed insert -snorkel fitting and from there into the engine.
Solution : Remove the snorkel .Wrap 2-3 times with 10 mm Teflon tape (plumber's tape ).
Re-install the snorkel.
Problem solved !


On the second photo ,notice the
"trail" of fines from the dirty side
towards the clean side .Maybe one more wrap is needed ...
Hack #2 : For better air filter seal ,the HD filter ( grey-purplish felt with white soft fleece on top ) can be sewed at its perimeter and at oval shaped hole ,just couple of mm close to the edge.This will increase the stiffness of the air filter around its perimeter ,thus providing more resistance to the top cover air box lips .Thus better seal.
Also it prevents the felt and fleece layers to come apart ,if the filter is frequently removed for cleaning with compressed air and /or washing with boiling water.
With these two hacks the fines issue is solved almost completely.
Periodically servicing the carb ,after doing these hacks ,revealed almost none fine particle presence inside the air intake (clean side ) channeling (towards the carb's venturi ) !

Hack #1 : Contrary to common belief the fine particles find their way inside the carb,crankcase and combustion chamber ,not from the air filter sealing weaknesses but from the insert on the air intake snorkel.
If the air filter is removed it clearly becomes visible that the insert has two oval shaped fitting gaps against the snorkel.One at the dirty side of the filter and the other ,positioned exactly opposite,at the clean side.Due to vacuum fine particles find their way inside this non-sealed insert -snorkel fitting and from there into the engine.
Solution : Remove the snorkel .Wrap 2-3 times with 10 mm Teflon tape (plumber's tape ).
Re-install the snorkel.
Problem solved !


On the second photo ,notice the
"trail" of fines from the dirty side
towards the clean side .Maybe one more wrap is needed ...
Hack #2 : For better air filter seal ,the HD filter ( grey-purplish felt with white soft fleece on top ) can be sewed at its perimeter and at oval shaped hole ,just couple of mm close to the edge.This will increase the stiffness of the air filter around its perimeter ,thus providing more resistance to the top cover air box lips .Thus better seal.
Also it prevents the felt and fleece layers to come apart ,if the filter is frequently removed for cleaning with compressed air and /or washing with boiling water.
With these two hacks the fines issue is solved almost completely.
Periodically servicing the carb ,after doing these hacks ,revealed almost none fine particle presence inside the air intake (clean side ) channeling (towards the carb's venturi ) !
