757 fuel CTR pumps
 

Anyone know why a CTR pump would pressurise (when selected on) with the engines turned off? Fuel panel closed.

Cheers

deleted as it was complete tosh, and far too embarassed to put my name to it!!

There is no centre-left-aft pump? You mean left aft? I mean centre left...

Sorry posted complete nonsense before. I felt sure it was something to do with APU, but APU feeds from dedicated DC or with AC left forward. Will think more before posting next time.

757 centre fuel pumps
 

Could be a problem with an engine speed card that controls several relays in different circuits.Any other problems noticed i.e status messages:sad:

gatbusdriver, understood! I refuse to let this one be a simple answer...been thinking about it for days!

Herr Bus, nothing else odd noticed but we where on the push and busy so possibly...aircraft was then fine down route (both press lights on).

The only thing that springs to mind is that something could possibly be wrong with the auto load shedding system, as both CTR pumps are meant to be inhibited with N3 and/or N2 <50%, i.e. when the engines are shut down...just my 2 pence worth, no expert though...

Faulty switch on re-fuelling panel door. It assumes the door is open and removes the inhibit on the Centre pumps. I've seen it before.

Thanks for the replies. Would the faulty switch be a temporamental thing? Indications where sensible later in the day.

The fueling panel door switch is a magnetically operated reed switch. Its common to see these misbehaving.

Its easy to see if the switch has failed in the door open mode, as the fueling panel door lights remain illuminated as you close and latch the door.

A good hard **** with a solid object is usually enough to get it working correctly. Failing that, it will need to be replaced.

Hi Golden Rivet

As an aircraft engineer the correct term for **** is 'Technical Tap'

Regards, RV

I've heard the term "percussive maintenance" used

Or "excercised with a percussion instrument"