Help me get this thing running!

[BigRed96]

I have a co-workers Stihl 038 AV that I replaced the fuel line, fuel filter, impulse, and sparkplug on using all Stihl parts but the plug. I also disassembled and ultrasonic cleaned the Tillitson carb on the saw. I then rebuilt using a carb kit from Stihl. I fueled the saw with fresh fuel and pulled the starter on choke till it popped. Moved the lever up one position to fast idle and pulled, and pulled, and pulled. Nothing. Put it back on choke, no pop. Look at the muffler and gas is coming out. I flooded it. Pulled the plug and blew out the gas and let the saw sit. Tried starting again and no pop or nothing on choke or high idle. Pulled plug again, blew out gas, pulled muffler to inspect piston, piston has some light scratching on one side. Saw blows 140 psi of compression. Check spark arrestor screen and it is clear. Pulled the carb to see if I put something in wrong, all looks good. Checked spark using tool and looks good. Reassemble everything and put the saw on choke, pops on the first pull. Go to fast idle and pops again, pull again and the same pop. Pull, pull, pull. What am I over looking? I didn't replace the needle valve, spring, and lever and didn't tweak the lever while the carb was apart. Please help before I pull my hair out.

 

[jmssaws]

The choke is hanging closed

 

[stihl_head1982]

I have a co-workers Stihl 038 AV that I replaced the fuel line, fuel filter, impulse, and sparkplug on using all Stihl parts but the plug. I also disassembled and ultrasonic cleaned the Tillitson carb on the saw. I then rebuilt using a carb kit from Stihl. I fueled the saw with fresh fuel and pulled the starter on choke till it popped. Moved the lever up one position to fast idle and pulled, and pulled, and pulled. Nothing. Put it back on choke, no pop. Look at the muffler and gas is coming out. I flooded it. Pulled the plug and blew out the gas and let the saw sit. Tried starting again and no pop or nothing on choke or high idle. Pulled plug again, blew out gas, pulled muffler to inspect piston, piston has some light scratching on one side. Saw blows 140 psi of compression. Check spark arrestor screen and it is clear. Pulled the carb to see if I put something in wrong, all looks good. Checked spark using tool and looks good. Reassemble everything and put the saw on choke, pops on the first pull. Go to fast idle and pops again, pull again and the same pop. Pull, pull, pull. What am I over looking? I didn't replace the needle valve, spring, and lever and didn't tweak the lever while the carb was apart. Please help before I pull my hair out.

Check your air filter. Besides the flap in the carb, the choke mechanism for these is also a flap inside the filter itself. May be malfunctioning. Sounds like it is flooding easily. Can you post a pic of how scored it is?

 

[Jughead]

switch the diaphragm and gasket in the carb.gasket should be on the carb main body.diaphram on top then the cover.

 

[Simondo]

Has the Tillitson carb on the 038 got a fork on the needle valve leaver ? if so then the metering diaphragm will have to hook in to the fork on instal. If you dont it will push on the metering leaver and not shut down the fuel flow.

 

[Simondo]

Also...It may be worth getting the piston to the top of its stroke and then upending the saw with the throttle pulled to get rid of the contents of the crank case back through the intake when you do get to the bottom of the flooding. There may be a lot of liquid in there and will flood out the engine.

 

[jmssaws]

If it popped on choke then flooded about all it can be is the choke hanging

 

[Redfin]

Once it pops on choke, pin the throttle, pull and report back.

 

[a. palmer jr.]

I replaced the Tillotson carb on mine with a Chinese knock off Bing carburetor and have had no trouble with it since. The plastic piece in the Tillotson that holds the inlet lever was so old the plastic was loose on the rod allowing it to pop out. Don't overtighten the bolts on the air filter or it will cause the choke to not work right..