I have a 6.5KW Onan Genset gas generator in a fire truck and the generator
Powers (4) 1,500 watt halogen (240 volt) lights. The generator was working fine
And now we have a problem of blowing the bulb/tubes in the all the lights.

The generator supplies a breaker box and then in turns feeds the lights.

There are two wires going to each light head, one goes to each end of
The quartz halogen fixture. My voltage meter is showing 240 volt on each
Wire.

The truck also has four 240 outlets and each outlet has 3 prongs. With my
Meter I'm showing 240 volts on two prongs. I'm no electrician but I thought
For a 240 volt system I should have 120 volts on two prongs.

The trucks also has two 120 volt outlets and I'm showing 240 volts on
My meter.

Where is my problem?

Thanks,

QCFE

The 240 V outlets should show 240 across the two hot and 120 volts from each one separately to ground. That gives you 240 volts. Without seeing the wiring, it would be hard to determine the reason for 240 on the 120 volt outlets. Check the generator to see that nothing has been moved to a wrong outlet.