As350 Fuel Drain

[zeroairspeed]

The BA and B2 have a recirculation fuel system, so if you have the pumps on the fuel will be in motion, therefor any contaminants will be suspended in the moving fuel. The system will purge with in 30 sec, this is why boost pumps on for 30 sec before start, to remove any air before start.

 

Sump & A/F filter, pumps off. ( its ok for air to be sucked into the filter)

 

The DA and D2 have a closed system like the jet ranger, fuel is not in motion and the system is not self purging, if you create an opening with no pressure fuel will be displaced by air, and air doesn't burn very well. No recirculation so air will not be purged, and head to the injectors.

 

Sump pumps off, filters pumps on.

 

 

Rob

 

this is my thought as well. that is why i started this. this is the way i was instructed and explained. but when i get around the discussion table, the different methods come out.

but i don't know why in the supplement for the AS350. the instruction is to turn the pumps on. maybe i will send a note to technical at eurocopter.

thanks guys. see, the same discussion is here

[Three_Per]

but i don't know why in the supplement for the AS350. the instruction is to turn the pumps on.

 

without running the pumps you may not know that your drain valve is stuck in the open position.

 

 

I told you why earlier...

[Three_Per]

also any machine currently equipped with a Purolator A/F fuel filter kit should have a placard on the bowl stating "drain fuel with boost pumps ON"

 

I can only speak for an Arriel setup. I have no clue what the LTS has for a fuel system, it could be gerbils running in wheels for all I know.

[new guy]

I can only speak for an Arriel setup. I have no clue what the LTS has for a fuel system, it could be gerbils running in wheels for all I know.

 

 

Your not supposed to let everyone know about the gerbils and the wheel thing.

[Over-Talk]

Does the gerbil-wheel spin the opposite direction in a French helicopter ???

[InspectorGadget]

No but the gerbils smoke unfiltered cigarettes.

 

Also, I agree with the pumps off filter purges (ONLY with an arriel) because as stated anything your trying to sump, will be circulated back to the tank before you can get back to the filter to sump with pumps on.

 

If your running with the aux filter, as most are, then open both filter sumps at the same time. This lets air into the system better and allows the fuel to sump out.

 

As stated though... If your running an LTS and you do this, you might be up a creek very quickly.

[skullcap]

Couple of things:

 

If you drain the fuel from the filters what truly matters is that you look at it,,,,have worked with more than one person who would drain the fuel on ground and somehow by the use of the force pehaps was able to determine the quality of fuel.

 

If you drain with pumps on make some mess and you do have the issue of fuel recirculation thus possible contaminants being forced into the filter itself due to the purging of system fuel returning to tank.

 

I teach our guys to drain with pumps off due to the fact the fuel you drain will be a great sample of quality plus is less messy. BUT, you must ensure a few things after draining the fuel:

 

1) turn the boost pump on and ensure the fuel is not leaking from filter drains.

 

2) open the cap of fuel tank and listen or look into tank to ensure the fuel is being purged thru systm and running back to tank. A freind of mine learned this the hard way by having the engine flame out when turning off boost pumps while running and the air not purged out of filters thus when the pump pressure was removed the engine sucked air and quit.

 

Pumps on is must in any system non purging though and have heard more than one story of filter drain not reset and the filter puking fuel. Another fella I used to know told me a story of himself not checking this and when took off noticed fuel level reducing at an alarming rate causing him to land and check... the fuel was pooring out of engine bay and thankfully did not catch fire....