Does running the fuel empty damage the fuel pump?
Thread Starter
Joined: Jul 2008
Posts: 959
Likes: 3
From: New Zealand
Does running the fuel empty damage the fuel pump?
Hi all,
Some fuel pumps/ignition systems I'm aware of can be damaged if run dry. I guess it is due to the loss of lubrication provided by the fuel. Is this the case with the R44 Raven II Lycoming injection system>
If I fly until the fuel is expended and the pump runs dry, will it damage the pump or injectors?
Thanks
JohnO
Some fuel pumps/ignition systems I'm aware of can be damaged if run dry. I guess it is due to the loss of lubrication provided by the fuel. Is this the case with the R44 Raven II Lycoming injection system>
If I fly until the fuel is expended and the pump runs dry, will it damage the pump or injectors?
Thanks
JohnO
Joined: Jun 2005
Aviation Qualifications: Spotter
Posts: 56
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From: heathrow
If I fly until the fuel is expended and the pump runs dry, will it damage the pump or injectors?
Why would you want to fly until the helicopter ran out of fuel? By doing this, a damaged fuel pump may well be the least of your problems.
Joined: Aug 2009
Aviation Qualifications: Military
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From: Texas
Joined: Nov 2008
Posts: 917
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From: UK
747 jock
He didn't say he wants to. There are some pilots that would like to know at which point on the fuel gauge the fuel runs out…
This can be done safely in a low hover. Not recommended though but do able none the less.
Personally if the fuel light is on I tend to go on time, but it would be nice to know when the gauge is reading zero the engine is still running in straight and level.
It probably would not damage the injectors though because the engine would stop. If that happens switch the boost pump off!
Why would you want to fly until the helicopter ran out of fuel? By doing this, a damaged fuel pump may well be the least of your problems.
This can be done safely in a low hover. Not recommended though but do able none the less.
Personally if the fuel light is on I tend to go on time, but it would be nice to know when the gauge is reading zero the engine is still running in straight and level.
It probably would not damage the injectors though because the engine would stop. If that happens switch the boost pump off!
Joined: Sep 2007
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From: USA
Wow, rough crowd! Although I have to admit many of the replies were hilarious.
The question in the OP does seem rather silly and definitely could have been phrased better, but it does actually bring up a valid concern with some recip engine fuel injection systems. A better question to ask is if it would cause damage to any fuel system components if the aircraft was operated until dry during a ground run.
The R44 II engine is a Lycoming IO-540 and there are 2 fuel pumps in the system. One is electrically driven and one is engine driven. Obviously the engine driven pump would no longer operate when the engine stopped. But the electrically driven pump can operate independently of the engine. In theory it would be possible to damage the pump elements of an electrically driven pump if it were operated for extended periods with no fuel flow (ie. dry). However, I don't know enough about the R44 II control systems to say if this condition can occur.
As for the injector nozzles, the engine will stop running if there is no fuel delivered by the pumps. So they will not be damaged.
The question in the OP does seem rather silly and definitely could have been phrased better, but it does actually bring up a valid concern with some recip engine fuel injection systems. A better question to ask is if it would cause damage to any fuel system components if the aircraft was operated until dry during a ground run.
The R44 II engine is a Lycoming IO-540 and there are 2 fuel pumps in the system. One is electrically driven and one is engine driven. Obviously the engine driven pump would no longer operate when the engine stopped. But the electrically driven pump can operate independently of the engine. In theory it would be possible to damage the pump elements of an electrically driven pump if it were operated for extended periods with no fuel flow (ie. dry). However, I don't know enough about the R44 II control systems to say if this condition can occur.
As for the injector nozzles, the engine will stop running if there is no fuel delivered by the pumps. So they will not be damaged.
Thread Starter
Joined: Jul 2008
Posts: 959
Likes: 3
From: New Zealand
Riff Raff, did you not note the date of my post? 
krypton john, as an international forum there are many here who would be significantly behind UnZud as the sun races around the earth.
Unfortunately an early morning 1st April post there appears as mid afternoon on the 31st March to many in the US of A!!
Splot
krypton john, as an international forum there are many here who would be significantly behind UnZud as the sun races around the earth.
Unfortunately an early morning 1st April post there appears as mid afternoon on the 31st March to many in the US of A!!
Splot
