M20F Engine Stumbling and Popping at Idle

[Flyman2456]

Update: Checked sniffle valve, timing, and adjusted idle mixture. Sniffle valve was not it. Mag timing was reset and idle mixture was adjusted. Mechanic checked for leaks and increased the idle mixture fuel flow and after some fine tuning, it did not stumble or pop on the ground after my last 1.5 hour flight. Going to take it up once more to confirm it doesnt have the issue on the ground..will post an update and confirm if that fixed it. Thanks!

Edited October 6, 2019 by Flyman2456

[Flyman2456]

Solved!!

Seems to be all it needed was an idle mixture adjustment. Through the process though, I now have all clean/two new plugs, a freshly timed engine, and a leak free intake. 

Thank you all for your comments and suggestions, glad to be a new member of the Mooney community!!

Thanks!!

 

[carusoam]

Great pirep, Flyman!

Glad you took the time to type and share the details...

Best regards,

-a-

[SLOWR426]

Flyman2456:  Our '67 M20F POH mentions popping on the ground if too rich.  I've been having this too, will try leaning more or idle mixture. Thanks.

[RobertGary1]

On 10/8/2019 at 4:36 PM, Flyman2456 said:

Solved!!

Seems to be all it needed was an idle mixture adjustment. 

 

I usually tell my students that if adding power on the ground causes an increase in rpm you’re probably running too rich. That’s only a slight exaggeration. On the injected Mooneys you want to taxi with the mixture close to the cut off position. Adding power for taxi involves moving both mixture and throttle.  
 

-Robert