Hello all,Thanks for the help with the FMC and D-> functions! It works for me now that I know how to do it! New question has arisen regarding the fuel system. I guess this is more of a "What am I doing wrong" type of question. Here's my scenario: :-)Loaded 737-700 so ZFW set at 112.9k lbs.Per flight manual, loaded max fuel in wing tanks and 1000lbs in center tank for total fuel weight of 18.2k lbs, need 15.0k lbs for flight. Now, here's where I had my first issue. Pushed back, started engines, all tanks feeding via overhead fuel switches, no cross feed.I noticed that the center tank was the only tank feeding, and thought "when it is emptied, the main tanks should start feeding." HA! Looks like I was wrong! After beautfil rotation and climbout, passing through 3.5 for 8, my engines shutoff! Master Warning lit and all the warning lights came on. Oh great. I checked the overhead and saw the "low pressure" lights on the center tank, while the main tanks seemed to be okay. I should have reviewed my inflight engine start procedures, but instead freaked out and decided to just set it down in the ocean. :-( FS9 reset the flight, and I decided to try again. . .this time I was at least at 7000 when the center tank emptied, and the engines again shut off. BUT! This time I new my inflight engine start procedures. . .and got them going while slowly sinking thorugh 4.5. The rest of the flight went off without a hitch except for ATC yelling at me to expedite my climb to 1-2-thousand. It would help if my ENGINES WERE ON! :-P Too bad we can't declare emergencies in FS yet! Anyway, after that long winded explanation, my question(s):What did I do wrong with my fuel settings? and how does the feed system work with the center tank and wing tanks? (ie center emtpies first then wings, or vice versa. . .etc.) Thanks for the help!-drew-

There is something funky about the center tanks that I don't understand. I am not sure if this is a bug or not, since PMDG has yet to comment upon it, but if the center tanks run dry with the repective fuel pumps on, the engines will quit no matter how much fuel you have in the wing tanks. The general solution is to shut off the fuel pumps on the center tanks before they are empty (or simply never turn them on in the first place). In the manual, under normal procedures (page 2), it states that the center pumps should NOT be tunrned on if there is less that 1000 pounds of fuel in them. Logically, I suppose this means that you should shut the center pumps off in flight whenever they reach or go below 1000 pounds of fuel. Hope this helps. WOuld be nice if PMDG could comment on this. Perhaps this the way it works on the real planeAndrew

Hi, I just completed a successfull flight from EGLL to EKCH loading 59% in both wing tanks and 29% in the centre tank (don't ask why those crazy percentages, it was just a way of letting more fuel into the left tank -- could not increase the fuel level in the left tank without also increasing the level in the centre). I turned on all pumps for the take off and climb out. As the centre tank depleted, I got a fuel message on the announciator, which made me turn off the pumps on the empty centre tank. Other than that, no action was required by me and I had no flameouts what so ever. I seem to remember, but do not quote me on it because I am no Boeing expert, that if there is fuel in the centre tank, that one will always be the one to feed the engines (provided that the pumps are on) because it has higher pump pressure than the two wing tank pumps.Hope this helps, :-wave Boaz Lev

All this input helps. Thanks everyone. I don't quite understand why on page 11 of the AOM it specifically says:"Main tanks 1 and 2 must be full if center tank contains more than 1000 lbs / 453 kgs." I must have just gotten lucky because my flight called for 18.2 which is the two mains full and 1000 in the center. If I spread the load with less in the wings and more in the center, I wouldn't be following this explicit direction. Any thoughts anyone? And is any one else experiencing the center tank empty/engine shutoff? Better yet, any real 737 pilots: would you just leave 1000 in the center tank and only use the wing tanks for the entire flight? This is interesting. :-) Gotta love this plane!Thanks again!-drew-

There is another post on this forum relating to this exact problem.From memory I believe it is a bug (PMDG will correct me if I'm wrong :-)), but the work around is to switch off the centre pumps before they run dry.Edited: Add URLhttp://forums.avsim.net/dcboard.php?az=sho...id=12051&page=6RegardsRussell Jourdain (NZL007/ZK-RHJ)

I just thought I would bump this thread, as a new user of the PMDG 737 I encountered this problem last night. I thought I might be usefull if it was a bit more visible in the fourm.It helped me anyway.Simon.

Yes had same problem last night shortly after departure from Anchorage (I had the right engine cut out - not both - after the center tank fuel was used up). I did neglect to turn off the center tank fuel pumps, and I'm not sure that any good captain would depart with only 1500 lbs or so in the center fuel tank. I suspect it is a bug that may have been introduced while fixing the fuel imbalance issue, I'm sure PMDG will clarify. I'd be pretty surprised if neglecting to secure the center fuel pumps would result in an engine failure in the real bird.Funny thing is, I remember something from the FAA about a year or so ago that temporarily grounded the 737NG fleet because of some issue with the fuel pumps that required and immediate fix...since that was about the same time I started riding the Aloha bird 2200nm over cold water between Hawaii and the mainland, it piqued my interest!regards,

Yes, this is a known issue. Be sure to switch off center tanks before 20 lbs are left. In real procedures you would switch them off before 1000 lbs are left in the tank. This keeps the pumps covered to avoid electric spark possibility if pumps are faulty.