M20C Fuel Sump Drain Leak after checking for water

[RonM2OC]

75 M20C Fuel Sump Drain Leaks after checking for water under starboard wing. I tried to reset drain sump by reinserting fuel sample bottle but still drips at one drop per 10 seconds or so fterwards. We temporary solved the slow dripping with a small round magnet (plugs hole) untill I can find the correct solutuiion(s). Any clues please.

[carusoam]

Ron,

 

As you would guess, the drains are a simple spring loaded valve.

 

You can remove and clean them quite easily.  They have a rubber seal, so don't over torque when replacing them.

 

You can also buy a new one if that makes you feel better.

 

Be careful when working with fuel, it spreads everywhere and can be ignited.

 

The usual case of some junk stuck in the valve seat can sometimes be alleviated just by draining, open and close the valve many many times.  It helps to have somebody available to pour the fuel back into the tank when this happens.

 

Look for what is causing the valve to stick open,  sealant, rust and paint chips often are found in M20C sumps,  (experience)....

 

I would not expect your magnet trick to hold back the drip at flying speeds.  Nor would you know if it is still there.

 

This is an easy A&P fix if you are not comfortable with the work.  It's not even Mooney specific.

 

Best regards, 

 

-a-

[Magnum]

Quote: RonM2OC

75 M20C Fuel Sump Drain Leaks after checking for water under starboard wing. I tried to reset drain sump by reinserting fuel sample bottle but still drips at one drop per 10 seconds or so fterwards. We temporary solved the slow dripping with a small round magnet (plugs hole) untill I can find the correct solutuiion(s). Any clues please.

[drapo]

Here is you answer from not so long ago...

http://www.mooneyspace.com/index.cfm?mainaction=posts&forumid=2&threadid=3282