Hi all,
In my experience with RB211's on the '74 Classics, if I didn't hear that low tone 'rumble' at light-off, I would always fuel chop it, allow it to motor, then select the fuel on again, and if the rumble was there, as it usually was, it would accelerate normally!
I found that, no rumble, no successful start, the engine would always stagnate around 40%.
If about 5 seconds went by with no rumble after light-off, fuel chop.
Doing it that way, would always save a lot of time, since letting it go without the rumble, allowing it to get to the stagnated start point, fuel chop, motoring it for cooling, and then selecting the fuel on again, took significantly longer.
That 'no rumble' happened about 10% of the time, per flight!
Cheers
