Paris12Man

Paris12Man

Well Known Member
On my second engine run, I noticed the smell of fuel after 10 minutes of run time. During engine inspection after shutdown, I noticed the tray under the right carburator was full of fuel. Can't find any threads or documentation on this issue. Has anyone experienced this before? Anyone know the cause of this? Left carburator tray was dry. Thanks, Steve
 
fuel pump

Don't start the engine but turn on your fuel pump and look and see were it is coming from.
 
Hey Steve - -

Some time back there was a discussion about that problem. If I remember right, you might have a float problem. You can take the bowl off, and fill it with fuel and see if both floats seem to be at the same height to start with.

John Bender
 
The fuel is being pumped out the short plastic tube of the carburator into the tray. This was verified by turning on the master switch and electric fuel pump. Not sure about disasembly of carburator....I will need to read up on some good documentation. Any pointers from anyone?
 
Something as small as a human hair caught between the needle valve and seat will cause that to happen. Easy to check and remove it.
Not sure if you can on the 12 or not, but an old trick is to drain the carb bowl dry, then hit the pump and it may wash out the hair or whatever is in there. Worth a try anyhow.
 
They had a batch of bad floaters that actually turned into sinkers. So the fuel bowl got too full as the floater is supposed to keep the fuel level in the bowl at a certain level. If it sinks it doesn't do that and the pump floods the bowl and the excess fuel is being drained. Don't ask me for references but I read about these problems about a year or so ago. You might have to go through their ridiculous warranty program to get the money for a replacement floater refunded if you got one of those sinkers.
 
Paris12Man said:
The fuel is being pumped out the short plastic tube of the carburator into the tray. This was verified by turning on the master switch and electric fuel pump. Not sure about disasembly of carburator....I will need to read up on some good documentation. Any pointers from anyone?
Click to expand...

the "short plastic tubes" are float chamber venting tubes. They allow leakages from your carb float chamber to spill onto the drip tray and not the exhaust. It should always be a very small amount unless you have a problem with the float chamber. I would pull off the chamber at the bottom by popping the clip and making sure you have two undamaged floats. Fill the chamber half full of fuel and see if both floats rise up the posts to the same level. Since you are still under warranty, I would call Leading Edge or Lockwood and explain the problem. You are uncertified so you can fix it. They will be happy to tell you how. If it turns out to be bad parts they will walk you through the warranty program. Either way, they will help you fix it. No you should not have fuel pouring out of these vent tubes.

Pete
 
Along with the float not floating we also found a brass sliver in the needle valve hole. We thought this was our problem at first, then discovered the sunk floats.
 
Cause and results

Findings.....I spoke with the technical department at Lockwood Aviation and they stated my problem was with the Float Needle valve. They needed to reset/adjust and to send in the carburetor. Lockwood Aviation provided very fast turn-around and I just completed the reinstall of the carb and I have no leaks :). Both floats were fine.
Now if I can only get my propeller hub back from Sensenich (over two weeks) I will continue with my engine run test.....come on Sensenich!!:confused:
 
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