Engine Start - only one engine fires.

[Guest allblack]

Guys, the 737-600/700 arrived in my mailbox last Friday, and I'm already in trouble on the domestic front, seems the lawns needed doing and I was otherwise preoccupied...This thing is fantastic.Anyway, I'm progressing through the manuals (the FMC is giving me nightmares, but I love it!) and I've come across a problem with engine starting.I spent about four hours yesterday trying to find my error, but realised that it might have me beat.I've progressed through the overhead panel, turned on the power, fuel pumps, hydraulic pumps, put the ISO switches on AUTO (apparently there's three but I can only find two) etc etc, moved the switch from "both" to right, and then turned the right engine knob to start.Nothing. I've checked and re-checked. Still nothing.However, when I move the switch to left, and then fire up the left engine, it bangs into life. Go back to the right engine: nothing.Given the left engine fires up, I kinda figured all the checks must have been done correctly, so why can't I get the right engine to go?Any suggestions would be much appreciated.CheersTim

[Mats_J 2]

Hi TimSounds like you don't have any bleed air from your APU to the right side engine. Check that your isolation valve is open. If not open in AUTO set it to ON.Hope it helps,

[Guest allblack]

Thanks Mats.The FM tells me to open three ISO valves, but I can only find two switches that have the word AUTO as on option. But I know I'm missing something. I seem to recall that the area concerned (middle-right side on overhead panel) doesn't have three switches with AUTO as an option, and I'll have another good look tonight.CheersTim

[Guest allblack]

Hi Mats,Just in case you read this again....I had another play just now, and checked everything and the right engine wouldn't start....I moved to a more scientific approach, and started clicking various buttons to see what would happen....The first button/switch I clicked on was the one DIRECTLY BELOW the right-hand side ISO valve switch.It's got ON/OFF with a 2 below it...Anyway, the second I clicked on it, the engine started up!This isn't in the manual (probably coz it's dodgy) but it seemed to work.Now I just need to figure out how to do it properly. Everytime I've done something, I've checked I've done it twice (left/right), and I've also had someone double-check my inputs.It works for others, so clearly I'm being dumb. But I'll get there.ThanksTim

[Qavion 19]

"The first button/switch I clicked on was the one DIRECTLY BELOW the right-hand side ISO valve switch.It's got ON/OFF with a 2 below it..."Hi, Tim...That's an Engine Bleed Switch (not officially an "isolation valve" switch)."Anyway, the second I clicked on it, the engine started up!"Look at how the overhead panel depicts the bleed air/pneumatic system. See how the air from the APU has to go through the official Isolation Valve (the one in the middle marked "CLOSE-AUTO-OPEN) to get the right hand side of the bleed system? The Isolation Valve will stop the air going through it if:1. the switch is in the CLOSEd position(obviously).2. the switch is in the AUTO position, but ONLY if ALL the Pack Switches and Engine Bleed switches are in the ON/AUTO/HI positions. That is, switching any one of these to OFF will open the Isolation Valve.Normally the Packs are switched OFF for engine start, so if the Isolation Valve is in the AUTO position, the Isolation Valve will open (as per the rule in "2").... and the air can get from the APU to the right hand side of the airplane.What you accidentally did to start the right hand engines was to trigger the logic in "2" to open the Isolation Valve. However, this is not the real world recommended method... BTW, after accidentally starting the engine in this way, I hope you made sure that the Engine Bleed Switch was returned to the ON position?Hope this makes sense.Cheers.Ian.P.S. This question has been asked... and answered... many times on the forum (hint, hint) ;-)

[Guest allblack]

Thanks Ian,I'll print out your response and take it home with me tonight.I agree the question has been asked, and I haven't had time to read every line in every post, but I see the most common response is RTFM!I agree with this, I'm a big believer in helping yourself before asking others, and I have RTFM numerous times (as did this other poster).We both followed the manual religiously, but the resolution was not there. I appreciate all the workings of a 737 can't be put in a 70-page small book, and interestingly the answers I saw to fix the problem, including yours, is not covered.The manual is great, but it's not the answer for everything.When I can (correctly) get the engines to go, I'm moving on to the FMC. Oh lordy, then the fun will begin!CheersTim