Does running the fuel empty damage the fuel pump?

[krypton_john]

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

[RotaryRat]

I'd just keep on flying, it's only a pump

[Freewheel]

Got what it deserved. :E

[747 jock]

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.

[HeliHenri]

Best way to know is to try and the good point is that you don't need to know if you're fitted or not with the new fuel bladder :}

[boratron]

Is this related to April fools day in anyway?

[FLY 7]

If you can modify the sender to not read below, say, 1/2 full, then you'll never run out of fuel.

[ascj]

Depends how hard you hit the ground

[Lonewolf_50]

If I fly until the fuel is expended and the pump runs dry, will it damage the pump or injectors?
Thanks
JohnO
If it does, you should be able to buff it out with 320 grit sand paper. :E









(Offered in the spirit of the day. :} )

[chopjock]

747 jock
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.

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!

[fleigle]

How would it damage the ignition???


Oh!, hitting the ground would do that, but cancels the Warrenty.

:E
f

[Reely340]

No worries, them pumps are built for that. We do that on almost every flight. By doing so we get impressive range and a complimentary EOL to round off the day.

P.

[Arnie Madsen]

.

It only harms the pump if you use April Fuel

[krypton_john]

Ha, thanks Arnie, and happy April Fuels Day to you, sir!

[turboeddie]

Don't worry, it is lubed by the oil not the fuel. No fooling. :=

Don't run out of either. :ooh:

[riff_raff]

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 (http://www.robinsonheli.com/r44_2_poh.html) is a Lycoming IO-540 (http://www.p28b.com/sites/default/files/Lycoming%2060297-10%20540%20Op%20v2006R3.pdf) and there are 2 fuel pumps in the system (http://www.robinsonheli.com/manuals/r44_mm/r44_mm_12.pdf). 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.

[krypton_john]

Riff Raff, did you not note the date of my post? :cool:




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

[Falcon Al]

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.

Damage is still possible ..... but not by fire.