Johnson Pump 0.2233.010 Lip Seal | C1AL F35B F4B

This is the genuine Johnson Pump lip seal, part number 0.2233.010, for the C1AL, F35B, and F4B series engine cooling pumps. It's a small part that does an important job. The lip seal rides on the pump shaft and keeps raw water on the wet side of the pump, away from the bearing and the drive end. When it's doing its job you never think about it. When it starts to go, you'll see it.

These Johnson pumps move cooling water through your engine, and the shaft that spins the impeller has to pass through the pump body. That's where this seal sits. Its flexible rubber lip wraps around the shaft and holds a tight, spring-loaded contact so water can't sneak past. It measures 0.48 inch on the inside diameter, 0.94 inch on the outside, and 0.27 inch thick, which is 12 by 24 by 7 millimeters in the manufacturer's own sizing. That's the same 12X24X7 seal Johnson specs into these pump bodies from the factory.

How do you know it's time for a new one? A weeping or dripping seal is the classic sign. If you spot water tracking down from the pump, or a little puddle under the drive end after a run, the lip seal is usually the culprit. Sometimes you'll catch it during an impeller change, which is the smart time to do it. The seal and the impeller are both wear parts, and both live right there in the same housing. So if you've got the pump apart to swap an impeller, dropping in a fresh lip seal while you're in there just makes sense. It's cheap insurance against pulling everything back apart in a month.

Why do these seals wear out in the first place? Heat, hours, and grit. Raw water isn't clean water. It carries fine sediment and salt, and over a season that slurry works away at the rubber lip and the shaft surface. The constant spin of the shaft adds friction and heat. Eventually the lip loses its grip, hardens a touch, and lets water past. That's normal. It's why the seal is sold as a replacement part and not something you install once and forget.

Fitment matters here, so measure before you order. This seal is built specifically for the C1AL, F35B, and F4B pumps. If your pump is one of those, you're in the right place. If you're not sure which pump you have, check the casting or the tag on the pump body, then confirm the 12 by 24 by 7 millimeter dimension against the seal you're pulling out. The old seal is your best reference. Match the inside diameter, the outside diameter, and the thickness, and you'll know you've got the right one.

Installation is straightforward for anyone who's serviced a raw-water pump before. Pull the old seal, clean the bore and the shaft, check the shaft for a wear groove where the old lip was riding, and press the new seal in square and flush. A little clean water or a marine-safe lubricant on the lip helps it seat and protects it on that first startup. Take your time and don't cock it in the bore. A seal pressed in crooked won't last.

This listing is for a single lip seal. It's the rubber sealing element only, not a full pump rebuild kit, so if your pump also needs an impeller, an O-ring, or a wear plate, grab those at the same time and do the whole job once. Keeping a spare seal in your onboard parts box is a smart move too. These are the kind of small parts that can strand a boat if they fail at the wrong time, and they take up almost no room in the spares bin.

We stock the genuine Johnson Pump part, not a guess-and-hope substitute. When you're sealing the cooling side of your engine, the right part number and the right dimensions are what keep water where it belongs. Order the 0.2233.010 and get your pump back to doing its job quietly.