HotDog: I'm referring to the -524H (&HT).
We position the FCS to run when:
a) EGT less than 100 deg C
b) N3 reaches 25%, or if 25% is not achievable, allow N3 to stabilise at max. motoring at or above 15% and . . .
c) N2 reaches 10%, or if 10% not achievable, allow N2 to stabilise at max. motoring
For the JT9, we use 5 seconds at max. motoring and a minimum of 15% N2.
For the CF6 (-80), we use max. motoring and a minimum of 15% N2.
Across all 3 of the engine types in our fleet, most pilots look for around 4% N1 before introducing the fuel. I doubt whether we can dispatch with inoperative N2 indications (EICAS), but your procedure for an inoperative gauge sounds good.
WG.