Chainsaw Smoke

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All the carb manufacturers have manuals on line to assist so no worries, it's all trial and error at first and even when you know what's going on a picky carb can suck[emoji3064]
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Ah yes I see. I'll have a look at it over the next few days, feels like that could be half the issue. Thank you

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If it was a mcculloch I would say it's burning bar oil. But I don't think stihls can do that w/ a gear driven pump rather then the macs impulse driven pump. Could the bar oil tank leak into the crankcase some how. If it was fuel rich wouldn't it be blue smoke? White smoke makes me think bar oil.
 
If it was a mcculloch I would say it's burning bar oil. But I don't think stihls can do that w/ a gear driven pump rather then the macs impulse driven pump. Could the bar oil tank leak into the crankcase some how. If it was fuel rich wouldn't it be blue smoke? White smoke makes me think bar oil.
This saw doesn't have an engine that shares a crankcase with the bar oil, so there is no way for bar oil to get into the engine. The saw simply needs to be tuned and ran long enough to burn off the oil.
 
Based on the videos it appears to be overly rich. However, it does have throttle response which is a little puzzling.

What have you done to the carb so far and is it OEM parts or China cr*p? I had a FS-85 trimmer do this once and it turned out that the metering diaphragm was stiff as cardboard.

Once the carb is sorted out I wouldn't completely rule out the ignition. If it is only firing occasionally it will leave a LOT of unburned oil in the engine and cause your smokescreen. There was a recent thread about a Husky with a similar issue and after about half a dozen pages of speculation the OP put up a video and an almost unanimous verdict came back "Coil!" New coil fixed it. While coils are higher reliability than carbs they DO fail occasionally.
 
Did you clean out the fuel tank ? Sometimes when the sit for long period the gas evaporates and the oil turnes to hard sludge. The fresh gas losses it up
Changed filter and checked tank, clean as a whistle, ty for your help though

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Hopefully this will get you in the ballpark.
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NOTE: that these settings will ONLY apply IF the limiter caps HAVEN'T EVER been removed. There are TWO carb settings one is BEFORE the limiter caps are installed and the one above is for AFTER.
 
So what is the history of HOW / WHY it became a non-runner? What did the previous owner say?
Just had it for a stupidly low price and said they couldnt get it running. Didnt ask many questions, seemed dirty but for the money was worth the risk of it being knackered

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Another good test at this point would be to try a pressure test of the fuel inlet in the carb. A good carb should hold 7-10 PSI indefinitely. If it leaks down then that is how your extra fuel is getting to the engine.
 
I had a look at the piston earlier to see if the cylinder was full of oil and something, and I can now see that the top surface of the piston looks like the surface of the moon. That cant be good?20200325_153317.jpg

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Pull the muffler and post a photo of the side of the piston as seen from the exhaust port.

Your photo above might be just carbon build up from improper running. Once it runs properly it will burn off.
 
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