Yes, it is mainly the float/auto switch that fails, and if the pump is mounted away from the bilge, then indeed the pump will last for ages. Whale does sell repair
kits. Maybe it is time to have one on board.
I am sure you are aware that the Gulper 220 has only limited pumping ability, like approx. 800 lt per hour (is that 200 gallon?), and if you compare that with a Rule
3700 that can pump (so the specs say) 14,000 lt (3700 gallon, funny
that the marketed capacity equals the model number.....).
The good thing is that the Gulper can pump most or all the water out of your bilge while other pumps may not, depending on the position and type of 'float/auto' switch.
The other advantage of the Gulper is that can pump easily dirt and debris, as this is a diaphram type of pump.
Edit, just noticed above post: I am with Hopcar, add a large volume pump for real flooding issues. The Whale Gulper might not be able to handle those.
BTW, I have a similar setup, Gulper, Rule x2 (all three with their own 'auto' switch) and a manual pump. the Gulper comes on first, the auto switches for the other pumps are located higher. ie each of these switches higher than the previous one.
The 'auto' switch for the manual pump is wet feet on the cabin