Frigoboat Loses Pressure When Turned On

[RBCurtis]

Hello, and thanks in advance for assistance.

Frigoboat freezer stopped working after sitting in tropics for five months.

Technician found and repaired leak at connection. The system holds pressure when turned off. As soon as the system is turned on, the pressure drops quickly.

Technician confirmed no leaks at connections and suspects a leak at the cap tube junction, or inside the evaporator plate.

I've not found descriptions of this behavior when searching. Any chance that this pressure drop when turned on is normal behavior?

Are the technician's suspicions of leak at the cap tube or in the evaporator plate reasonable?

Thanks again!