high and low carb settings

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japfpe

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I have an older John Deere 60V saw I recently acquired sans owner manual. The saw intially ran like crap and once I cleaned the fuel tank out and perfromed some "gross" adjustments on the high and low carb setttings, it runs ok. I'm looking for some generic guidance on setting the high and low settings. The saw seems to not have the high end power that it should. It "bogs" under large cutting loads. Also the idle speed is too fast.

Thanks,
Joe
 
I believe the standard for older saws is to turn the screws all the way in (not too hard or you will damage them) and then come out 1-2 turns. The idle speed is a separate screw which you can simply turn down until the chain stops moving at idle. When the high speed jet is set right the saw will "burble" or four stroke at WOT with no load on it. At Madsens web site they have an excellent recording you can download which is will tell you exactly what the saw should sound like. Good luck
 
First if your fuel tank was full of junk , im sure you have some junk inside your carb. Their will be a screen in there most likely blocking fuel flow. That will give you some not so good performance on the top end.
 
I was taught to adjust the high end screw first, while running at full throttle. This can be done easier with a second person to help hold the saw in place. Most shops use a tach, but you can get it pretty darn close by ear. When you get the high end right, then you adjust the low end to where you can throttle up without bogging. Lastly, you adjust the idle screw. Sometimes it helps to crank up the idle a little during adjustment so the saw doesn't die as much. Once the adjustments are close, fine tuning should be done in very small increments, like 1/16 of a turn at a time.
 
i was taught a bit different and this way only requires one person and no tac. first after you get your initial adjustment completed on the carb get the saw so she runs. then start to adjust the low mix turn it till she runs at a smooth idle don't worry about if the chain is running at this point or not mess with that later. then hit the gas and see how she accelerates. if she is boggy turn the screw one way or the other and get it so she accelerates nicely. and then have a piece of wood handy and get her cutting and depending on how much power she has do some fine adjustments on the high jet to get her at her peak. now if you want the set the idle ply with that screw. i learned that courtsey of the homelite owners manual. :) it works fine and gives you quick results.
 
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