Won't Idle
- Thread starter msb1766
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treeclimber165
Member A.K.A Skwerl
I had an old 025 that did the same thing, the spark plug was loose.
An engine needs 3 things to operate properly. Fuel (gas and air in the proper proportions) Spark (at the proper timing) and compression. Your problem could be any of the 3. Check to see you have compression. If it is low, determine why. Check that you have spark. Check fuel (fuel lines, carb).
Once you determine which of the 3 systems is not working, you can trace it down. My old man taught me this and it has helped me tremendously over the years.
It could be as simple as adjusting the low speed jet. Most older poulans were 1 1/4 turns out from bottom on both screws (as a basic starting point).
An engine needs 3 things to operate properly. Fuel (gas and air in the proper proportions) Spark (at the proper timing) and compression. Your problem could be any of the 3. Check to see you have compression. If it is low, determine why. Check that you have spark. Check fuel (fuel lines, carb).
Once you determine which of the 3 systems is not working, you can trace it down. My old man taught me this and it has helped me tremendously over the years.
It could be as simple as adjusting the low speed jet. Most older poulans were 1 1/4 turns out from bottom on both screws (as a basic starting point).
treeclimber165
Member A.K.A Skwerl
The L and H are the low and high end jets. They control the amount of gas allowed to flow at low and high speeds. To check these, GENTLY turn them all the way in, counting the turns. Start with the high end (H). It should be about 1 1/4-1 1/2 turns out. Further out is richer, closing it down is leaner. Put it back where it was before you started, keeping in mind if it may be lean or rich. Then check the low end, putting it back where it was but keeping in mind if it was lean or rich.
Start the saw and let it warm up a minute. While running it full throttle (a vise is helpful for this, so you don't have a full speed chainsaw flailing around), Adjust the high end for highest RPM's, then keep richening it up (counter-clockwise) until it just starts to '4-cycle', or gurgle a tad. This should be fairly close to 1 1/4-1 1/2 turns out.
Let the saw idle. If it won't idle, set the screw at your basic starting point (1 1/4-1 1/2 turns). When you can get it to idle (you may need to turn up the idle set screw a tad temporarily), pull the throttle. The saw should accelerate without bogging. If it bogs, it is too rich or too lean. Heavy exhaust smoke indicates too rich. Adjust untill the saw accelerates from idle without bogging.
Re-set you idle screw down until the chain does not spin at an idle. Re-check the low end setting by pulling the throttle and listening.
A lot of this is 'feel', knowing what a properly running saw should sound like and figuring out which way to adjust to make it right.
Start the saw and let it warm up a minute. While running it full throttle (a vise is helpful for this, so you don't have a full speed chainsaw flailing around), Adjust the high end for highest RPM's, then keep richening it up (counter-clockwise) until it just starts to '4-cycle', or gurgle a tad. This should be fairly close to 1 1/4-1 1/2 turns out.
Let the saw idle. If it won't idle, set the screw at your basic starting point (1 1/4-1 1/2 turns). When you can get it to idle (you may need to turn up the idle set screw a tad temporarily), pull the throttle. The saw should accelerate without bogging. If it bogs, it is too rich or too lean. Heavy exhaust smoke indicates too rich. Adjust untill the saw accelerates from idle without bogging.
Re-set you idle screw down until the chain does not spin at an idle. Re-check the low end setting by pulling the throttle and listening.
A lot of this is 'feel', knowing what a properly running saw should sound like and figuring out which way to adjust to make it right.
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Good description treeclimber165!!! Rich.
tony marks
Addicted to ArboristSite
not about u question. but dont u think that thing would be a lot better w a decompression valve. i kinda thought the saw would have been fine ,if it had a bar that would hold a chain and the decompression.i guess that was an anti kickback bar. but to me the issued bar was not somethin to take to the woods
with u. in any case it wasnt my problem very long.
now that aint bashing ,just being specific about my thoughts on that saw
with u. in any case it wasnt my problem very long.
now that aint bashing ,just being specific about my thoughts on that saw
Wow, very good....
that stuff is still mystic to me!
but i know that:
screws and jets are fine soft metal!
on the 'spooky' side of the untraceable phantoms;
exists the possibility that after 3,000 fires something is warmed up enough to expand, and lose some ratio (fuel)or compression; sometimes spraying WD40 around possible places while listening for rpm raise can help trace.
that stuff is still mystic to me!
but i know that:
screws and jets are fine soft metal!
on the 'spooky' side of the untraceable phantoms;
exists the possibility that after 3,000 fires something is warmed up enough to expand, and lose some ratio (fuel)or compression; sometimes spraying WD40 around possible places while listening for rpm raise can help trace.
Fish
Tree Freak
Check the fuel and impulse lines, as well as the fuel tank vent,
but double check the impulse line.
but double check the impulse line.
