Merlin 140XBL startup issues.
 

I have a new turbine Merlin 140XBL. When I tested the turbine on a test bench, occasionally the startup fails on ignition.

I can hear and detect that there is ignition but the temperature is increased from around 30Deg very slowly and I think the ignition is timing out.

What is happening is that just after the ignition it will stay in that status for a couple of seconds that the ignition stops. The cooling motor will keep running for another couple of seconds then it stops. This happened one time on the test bench.

When I install the turbine in the plane, this got worst and sometimes it needs around three attempts to get successful startup.
Can you please indicate what may be I am doing wrong?

Regards
Vince