We got this non running tiller used. It has good compression and spark. Now I have put a new carburetor on it, but it still won't run. It may have tried to fire a time or two. The primer bulb fills with fuel with no trouble. I wonder if I got a defective carburetor. Could the fuel line be bad even though the priming bulb easily fills? Any suggestions on what to do or check?
If you haven't already pull the muffler apart and check for mud wasps in the outlet. There is also a screen inside that can become plugged with carbon. I had both happen to mine and it wouldn't start either time.
As cwn877 says, check muffler for obstruction. And look at piston and ring when muffler off. Is plug wet or dry after no start? Does carb need tuning? Turn idle screw CW to max it. May need to open L screw CCW. If you push the bulb and see fuel moving in and out the lines - probably ok. A good test is put a tsp of fuel in the plug hole, pull rope 2x, re-insert plug, pull rope to start - may take 6-8 pulls. If engine doesn't run strong for 1-3 secs, you have compression, spark or timing trouble.
Stihl likes to use those cone shaped spark arresters in their mufflers. They plug up real bad. The coned shaped arresters unthread from the muffler.
That's what the problem was. The muffler screen was plugged completely off. It runs great after cleaning it out. I think the tiller has very few hours. Thanks to everyone!
