stagekraft
Active OPE Member
Hey All,
Newbie to this forum, but hoping for a point in the right direction...
I have a small Stihl chainsaw, bought it used last year and it ran great until this summer.
I'm pretty sure it was some old/bad gas mix that created my problem.
The engine starts and idles fine, but when you try to rev up it falls on its face.
You can nurse the trigger and get it to rev up some, but no real power.
A search of the web brought be back dozens of references to this, but all seem to conclude that the problem can be resolved by;
Cleaning the spark arrest screen
Replacing the spark plug
Replacing the air filter
Replacing the fuel filter
None of which has resolved the problem...
What it really feels like to me is that the high speed mixture is off.
But this is a MS170 with the "018" engine, which does not have a high speed screw.
(according to the manual, the carb is so precisely engineered that it doesn't need a high speed adjustment).
So, I'm thinking, OK there is not an adjustment, but there has to be some sort of jet that meters the fuel,
perhaps the bad gas has gummed up this jet therefore throwing the mixture off.
Which leads me here to this forum, seeking some knowledge.
Anyone here familiar with this problem?
Am I thinking in the right direction?
Looking for some knowledgeable opinions before tearing into this little carb...
Regards,
JohnR
Newbie to this forum, but hoping for a point in the right direction...
I have a small Stihl chainsaw, bought it used last year and it ran great until this summer.
I'm pretty sure it was some old/bad gas mix that created my problem.
The engine starts and idles fine, but when you try to rev up it falls on its face.
You can nurse the trigger and get it to rev up some, but no real power.
A search of the web brought be back dozens of references to this, but all seem to conclude that the problem can be resolved by;
Cleaning the spark arrest screen
Replacing the spark plug
Replacing the air filter
Replacing the fuel filter
None of which has resolved the problem...
What it really feels like to me is that the high speed mixture is off.
But this is a MS170 with the "018" engine, which does not have a high speed screw.
(according to the manual, the carb is so precisely engineered that it doesn't need a high speed adjustment).
So, I'm thinking, OK there is not an adjustment, but there has to be some sort of jet that meters the fuel,
perhaps the bad gas has gummed up this jet therefore throwing the mixture off.
Which leads me here to this forum, seeking some knowledge.
Anyone here familiar with this problem?
Am I thinking in the right direction?
Looking for some knowledgeable opinions before tearing into this little carb...
Regards,
JohnR