Whale Gulper 220 Service Kit AK1550 Diaphragm & Valves

The Whale AK1550 is the factory service kit for the Gulper 220 gray water pump, and it holds the two parts that actually wear out: the diaphragm and the valves. If your Gulper 220 has lost suction, started leaking from the vent holes, or just won't move shower water the way it used to, nine times out of ten it's these parts, not the motor. This kit gets the pump back to pumping without buying a whole new unit.

How do you know it's time? Weak or dropping flow is the classic sign. Water weeping from the pump's vent holes means the diaphragm has split. A pump that used to self-prime and now won't pull is usually valves that have gone hard or stopped sealing. None of that means the pump is dead. It means the wear parts have done their time, and it's time for the kit.

Here's the thing about the Gulper 220. It's a diaphragm pump built to handle the nasty stuff, shower and sink gray water full of hair, soap gel, and grit. That's a hard job, and the diaphragm and valves take the abuse. Whale designed the pump so those wear parts are serviceable, which is exactly why this kit exists. You rebuild the pump end, keep the motor and housing you already have, and you're back in business for a fraction of the cost of replacement.

The kit fits both versions of the Gulper 220. The BP1552 is the 12-volt pump and the BP1554 is the 24-volt pump, and the AK1550 services both. Check the part number on your pump body before you order so you know you've got the right unit, but the wear parts themselves are common to the Gulper 220 platform.

What you get is the diaphragm and the valve set. The Gulper 220 runs a single large Santoprene diaphragm, and Santoprene holds up well against the detergents and greases that live in gray water. The valves are Whale's non-choke design, the ones that let the pump swallow hair and gel without clogging the way a lot of waste pumps do. Replace both at the same time. If the diaphragm has worn, the valves usually aren't far behind, and you don't want to have the pump apart twice.

The job itself is straightforward for anyone comfortable with a screwdriver. The pump head comes apart with a few screws, the old diaphragm and valves come out, and the new ones drop in. One tip from folks who do this a lot: lubricate the new valves with silicone grease, never petroleum grease. Petroleum can swell the elastomer and ruin a fresh set of valves. And after you button it up, cycle the pump so the new valves seat properly before you rely on it.

Where does this pump live? Usually under a shower sole or behind a sink cabinet on a sailboat or cruiser, moving gray water to a holding tank or overboard. The Gulper 220 self-primes and will run dry without damaging itself, which is forgiving in a real boat plumbing setup where the pump doesn't always have water sitting at the inlet. Keeping fresh diaphragm and valves in it is what keeps that reliability intact.

A little maintenance goes a long way. Gray water full of food particles and hair is what chews these parts up, so flushing fresh water through the system now and then extends the life of the diaphragm. Some boaters add a fine mesh strainer upstream to catch the worst of the solids before they reach the valves. Do that, service it when flow drops off, and a Gulper 220 will keep working for years.

One thing to be clear on: this is a repair kit, not a pump. It's the diaphragm and valves only. If you need the complete Gulper 220 pump, that's a separate part. Order this kit when you've already got the pump and you're bringing it back to life.