Fischer Panda starts but stops after releasing start button

[sy_imagine]

In February I serviced the Fischer Panda Generator 6 from 1998. I changed oil, oil filter, and fuel filter. The engine then ran perfectly. Since I had forgotten the air filter, I made up for it later; I have not yet done another test. What's going to go wrong?
Today I ran the generator. It starts and runs at the operating speed, but it dies a few seconds after releasing the start button. Switching off all consumers and opening the air filter housing was of no use. The Volvo runs, so I rule out a diesel plague.
Could it be that I bent or tore something off while dismantling or installing the soundproof housing? A throttle cable, for example?
Of course, I opened the seacock and water came out of the exhaust during the start-up phase. Apart from that, the generator runs for quite a while without seawater until it switches off automatically due to the risk of overheating. I already tested this feature involuntarily. 
Translated with Google, sorry if it sounds strange sometimes.

[tckearney]

Sounds to me like the generator either does not no its running,  Ie cant see frequency or revs,  is there a rev counter? Or otherwise maybe oil pressure, this will be overiden while you are pressing the start button but if it has low pressure cut out it will then stop whe the button is released.  I am not familiar with the particular type you mention.  You could have knocked a sensor plug

[sy_imagine]

You could have knocked a sensor plug

It was exactly like that. This morning I noticed that I loosened one of the two exhaust temperature switches while installing the rear half of the noise protection box. The electronics responded correctly and switched off the motor. Now it's working again.