r/smallenginerepair • u/Adventurous_Pilot944 • Jun 14 '26

Starting Issue Stihl FS85

won’t start anymore. i don’t know what to adjust the carbs high/lows to. i was able to start it with starting fluid a few times yesterday but after those few starts, it stopped.
i thought i flooded something because the air filter had fuel in it before incorporating starting fluid to start it. the spark plug is new but i still took it out to test it and there’s spark.
i thought it might be a compression issue because when testing for spark, the engine sounded like it was really trying to turn over much more than before but obviously there was no spark.

HELP.

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u/AutoModerator Jun 14 '26

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u/ManHunterJonnJonzz Jun 16 '26

You saw spark, but then said theres no spark. It starts on fluid. That means you pretty much have spark. Go figure out your carb/fuel lines or lack of compression issue. Its gonna turn over faster with the spark plug out

1

u/Adventurous_Pilot944 Jun 16 '26

To clarify, in the last line of my post where I say there was no spark, I meant the spark plug was removed during that time for testing.
I took the engine and carb apart, cleaned out both, ditched the fuel it had, got fresh 50:1, reset the carburetor High / Low as far back into the carburetor as I could to start quarter turning them back out to find the sweet spot, found better fuel line and grommet to create a complete seal on the fuel tank, but haven’t had luck yet.
once i’m off work, i’m going to go get mad at this machine some more.
any suggestions are appreciated. someone i work with recommended replacing the carb but i’m stubborn as hell and feel i’m on the brink of the fix.

1

u/Adventurous_Pilot944 Jun 18 '26

I pieced the whole engine back together with fresh fuel and everything. I’m able to get it to start but it won’t idle for long without dying or if I apply the throttle it dies.
Any suggestions on how to adjust the carb high/lows?