Carburetor Question

[Douglas Firbanks]

Hello everyone! I had a quick question regarding carburetor function. I tuned my new carb on my CS-590 to an idle speed of 2800 RPM with a tachometer, after I blipped the throttle a few times and let it settle back down the idle speed was about 3100 RPM. Is this normal or a cause for concern?

 

[Old2stroke]

Get rid of the tach and do a search on how to tune a chainsaw

 

[buzz sawyer]

How long had it been it running when you set it at 2800 - compared to how long when it was at 3100? IF tuned correctly, it should be just a tad rich at idle. When you blip the throttle, it is clearing out the excess fuel so it may idle a little faster for a brief period.

Also, how old is the saw? Have you done a vac/pressure test recently?

 

[Douglas Firbanks]

How long had it been it running when you set it at 2800 - compared to how long when it was at 3100? IF tuned correctly, it should be just a tad rich at idle. When you blip the throttle, it is clearing out the excess fuel so it may idle a little faster for a brief period.

Also, how old is the saw? Have you done a vac/pressure test recently?

I have vac/pressure tested it a day ago and it passed. I had let the saw run for a few minutes at 2800 I only blipped the throttle and then checked again. Your statement about the saw clearing out excess fuel makes sense as it runs fine otherwise.