[Doug Linville]

Doug Linville on May 19, 2024 at 11:01 am #22531

Steve,
I flew the airplane a couple weeks ago with no issue. Also, flew three legs yesterday with probably two and a half hours flight time, no problem. Maybe caused by inactivity. Going to write it off for now.
Thanks,
Doug be

[STEVE]

STEVE on April 29, 2024 at 10:04 am #22504

Thanks Doug,
Steve

[Doug Linville]

Doug Linville on April 26, 2024 at 2:22 pm #22499

Steve, thanks for your reply.  There are no mechanics or FBO at K19, so, troubleshooting is very slow.  Will keep you updated.
doug

[STEVE]

STEVE on April 23, 2024 at 11:41 am #22493

Doug, 
There’s another thing that can cause an inability to idle normally; that’s an induction leak. Check to see if any of the primer tubes have broken, or been abraded through, and that all the hoses and clamps on the individual intake tubes are intact.

Steve

[STEVE]

STEVE on April 22, 2024 at 10:34 am #22490

Hi Doug;

It sounds like there’s a problem with the idle circuit in your carburetor, but before we start pulling parts I want you to look closely at the carburetor air box. Is it free of all obstructions (bird nests, etc.) because when an airplane sits, even if its in a hangar birds and other creatures (mice) can move in and build a home.

If that’s all clear then I want you or your mechanic to gently turn the carburetor idle mixture screw in (clockwise when viewed from the knob end) until it bottoms. Gently, don’t force it. Once it bottoms then back it out 2 1/.2 turns.
Then try starting the engine. If the carburetor is working as it should the engine should idle down to the previous 700-800 range. When the idle mixture and idle speed adjustments are correct , you may be able to slow it down to a 600 rpm idle.

If those actions don’t make a difference, I recommend pulling the carburetor finger screen. It’s accessed by either disconnecting the fuel in line at the carburetor, then unbending the copper washer locking tabs holding the large head of the screen prior to backing it out. 
The finger strainer should be clean as a whistle. If not, clean it prior to re installing it with a new locking washer.(MC16-A48 fuel inlet gasket available from Aircraft Spruce and Specialty (www.aircraftspruce.com) and other aero parts houses.

Finally, it’s a good idea to drain the fuel bowl on the carburetor every annual. It’s simple. Turn off the fuel valve, get your fire bottle handy, then removed the internal wrenching plug at the bottom of the carburetor fuel bowl. The fuel that runs out should be clean. Replace the plug, turn the fuel back on and check for leaks at the plug. 

These actions comprise the steps that should be taken at every annual inspection. If the problem persists, I recommend sending the carburetor to the folks at Marvel Schebler Carburetors. They will test it for free. Contact them at http://www.msacarbs.com

Please let me know what you find. 

Steve
 

Attachments:

• carbfingerscreen.jpg
• CarbFingerScreen.JPG

[Doug Linville]

Doug Linville on April 21, 2024 at 11:10 am #22488

I own a 1961 PA-24 250.  I have owned this airplane since 2002.  The airplane has sit in the hanger a lot this winter.  When i started the plane a couple weeks ago, it idled rough and then died.  I was able to restart the engine but decided to put it back in the hangar, open the cowel and look for anything unusual.  Didn’t find anything.

Returned to the hangar a week or so later, started engine without problem, idled smoother but within about 15 seconds it died, fuel pressure was good.  When the engine starts to die, haven’t been able to stop it from dieing.  Taxied to runway, completed a run up with all being good, so went flying without incident.

The airplane hasn’t done this previously.  Any ideas what could cause this.  The engine is a Lycoming O 540.  Normally idles in the 700-800 RPM range.  I ran it about 1000 RPMs trying to keep it from dieing.