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Fuel residue on shutdown
Once I had, he knocked on the storm window, and said, "Hey, there is something leaking out of your plane." I told him that it was 55 years old and there is always something leaking out. In all seriousness though, it was new to me. About two or three teaspoons of thick blue residue, rather like oil, and smells like fuel, slopped out of the cowl at the front gear well, and dripped onto the forks and a bit on the tire. Photos below.
I've seen staining like this on the aluminum structure before but it was always slight. I reproduced the effect the next day on an approach into Nipawin and called ahead to get a person to witness the shutdown, and the same thing happened. Just as the engine gasps its last a few spurts of the blue stuff slops out onto the wheel.
I crawled around underneath and absolutely cannot see where this is coming from. There is no sign of it on the engine sump, or rods, or cylinders, or on the inside of the lower cowl. There is a little bit clinging to the underside of the cowl along the edge of the wheel well, and it drips down right at the wheel where the opening gets larger.
Any ideas?
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Timothy Poole- Posts: 122
- Joined: Tue Oct 28, 2014 8:43 pm
- Location: KVKX
Re: Fuel residue on shutdown
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Timothy Poole- Posts: 122
- Joined: Tue Oct 28, 2014 8:43 pm
- Location: KVKX
Re: Fuel residue on shutdown
- Charles
Charles Schefer- Posts: 563
- Joined: Mon Mar 12, 2012 7:09 pm
Re: Fuel residue on shutdown
If I think of fuel related things that I have changed recently, perhaps that is it. I'll go back to a two or three stroke prime and see if the residue stops.
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Have you cleaned the primer nozzles recently? Six priming squirts on top of 3 throttle pumps shouldn't be necessary for your engine to start.
Tim
Timothy Poole- Posts: 122
- Joined: Tue Oct 28, 2014 8:43 pm
- Location: KVKX
Re: Fuel residue on shutdown
Not so. A stream of gasoline was shooting onto the exhaust shroud back there. It was evaporating (and perhaps burning a bit) in the windstorm during flight, and the residue would drip out the bottom on shutdown.
Why no one thought to just turn on the electric fuel pump on the ground and have a look far far earlier is a completely different question...
Anyways, it's fixed now, and no one died in a fire, and my last flight to Edmonton and back (6.5 hours) cost way way less money and the engine compartment was much cleaner and smelled way way nicer.
So that is all good.
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Tim
Timothy Poole- Posts: 122
- Joined: Tue Oct 28, 2014 8:43 pm
- Location: KVKX
Re: Fuel residue on shutdown
Clarence
- Clarence Beintema
- ICS member
- Posts: 134
- Joined: Tue May 11, 2010 11:41 pm
Re: Fuel residue on shutdown
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Gene Ridder- Posts: 14
- Joined: Fri Mar 16, 2012 2:04 am
- Location: NW Indiana
Re: Fuel residue on shutdown
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Fuel residue on shutdown
Gene Ridder- Posts: 14
- Joined: Fri Mar 16, 2012 2:04 am
- Location: NW Indiana