Having difficulties running AC compressors from a generator on a boat
You have provided no current measurements so we have no idea how much of an overload you are presenting to your generator.

Your options are:


Get a bigger generator.
Shed load during AC compressor starting so that the AC doesn't overload the generator.
Sequence the AC compressors, if there is more than one, so that only one is drawing starting current at any time.
See if a soft-start is available for the compressors.
See if the compressors can be started off-line. i.e., Is there any decompression valve that will reduce the mechanical load on the motor during start.