Homelite 240 Blowing gas, won't stay running

[andyfnp]

Hello, I'm new to the site but not to Homelite! I have 6 Homelite saws, from a 330, a couple of Super 2's, an XL, a CS-40, and a 240. Few other part saws put away. I cut my own firewood and burn 6 or so full cords a winter.

I was given this 240 a couple of years ago and was told it "won't run". On the shelf since then and decided to get 'er going this winter. Needed a coil first, then it would start, run erratically, drip black fuel from the muffler and die within 2-3 minutes.

Rebuilt the Zama C1S H4 XX B carb with the Zama RB 5 kit, new carb to manifold gasket, too. Mix screws set to one turn out after the rebuild. Saw started on 3rd pull, ran strong, no smoking as before. Jumped with each trigger pull.

Thought it was a done deal. Then in 2-3 minutes again, it started running erratically, fuel started spraying from seemingly the gas cap vent, and died. No restart until cooled down, then pretty much the same scenario.

Any suggestions? Too lean and overheating? Bad mix screw seats? I've not had a small engine to a shop EVER but I like this beefy little saw and would like to get it going, but I'm stumped.

Compression is good and holds at 140 pounds BTW.

Thanks for any help.

Andy

[karla48]

Andyfnp, Is your "Carb Adapter Seal" good? I'm kind of thinking maybe its an air leak, so I would check your Carb gaskets and engine seals. When troubleshooting, I use a process of elimination. Check for good fuel, good fuel filter and lines next, then the carburator, and obviously compression, and spark. And when the engine runs erratic, assuming you eliminated everything else, check for Air leaks! I hope this helps.

[karla48]

Oh, also if your gas tank has a "duckbill" in it to vent the tank, don't forget to check/ replace the vent If its not venting properly. (Note: The Duckbill is a combination check valve and vent for the fuel tank).