737-500 Start problem

[Pandabear]

Greetings all,

Need some ideas on a start problem on a CFM fitted to a 737-500.

When I raise the start lever to idle, there is no light up on the first attempt.
Run the checklist, make a second start attempt and off she goes, no problem.
Problem doesnt happen on every sector, but seems to be every 3rd or so flight.

-Doesnt matter whether using L or R ignition, or Both for that matter.
-Fuel valve opens BUT NO fuel flow registers on flow meter.
-"jiggling" the start lever doesnt help either!

The following have been checked by the engineers...

1)Both ignitor plugs checked-ok
2) Ignitor leads checked -ok
3) Ignition check carried out-ok
4) Wet motoring done-fuel exits exhaust
5) Engine start carried out on each engine with each ignitor-ok
6) Start switches in pedastal cleaned inspected-ok
7) Blue position light for eng shut off valve corespond to valve pos
8) Fuel shutoff valve corespond to start lever and lights
9) Fuel shut off valve on mec opens and closes with start lever pos
10) No fuel filter bypass light on

I am sure the engineers have sorted it out by now but I thought I might throw it out there and see if anyone has had a similar problem.

Cheers

[Pandabear]

Thanks for the quick reply, looks as though the fuel pump needs to be replaced- that will make the accountants happy!