This article will help you diagnose the cause of a drip from your impeller housing weep hole and will walk you through the steps required to fix the problem.

I'm seeing a steady drip from the bottom of my impeller on the serpentine belt end of my engine. I've swapped the impeller and the drip continues. What is going on?

The drip is the result of a problem with your raw water cooling system. In the simplest of cases, it's a problem with the shaft sealing ring, an inexpensive part. At worst, the ring has been damaged for a long period of time and the problem is related to bearings on the raw water pump which cause uneven rotation and will be a problem regardless of seal replacement.

On a penta engine, you must remove the bracket that holds the impeller housing in place first. It's 2 bolts and requires a socket set with a 1 ft extension. If you don't have the right tools for your boat, this will be a hard task. With the right tools, it's easy. Remove the bracket.

The impeller housing requires the removal of 4 flathead screws. The hoses are flexible enough to just pull it to the side after the screws are removed. Once you pull the housing off, you will see the impeller in the housing. Note the direction that the splines are facing on the impeller as this indicates the rotation direction. Also note the condition of the splines. If any are missing, order a new impeller and install the new one.There is also a sealing gasket on the water pump itself. Replace it with the sealing gasket included with the new impeller. This is a round approximately 4" ring.

Now you need to check the raw water pump to see if there is any play or noise in the bearings. It is the part that spins and is still connected to the shaft. It should spin smoothly with no hint of grinding. It should also not wobble laterally. If you sense it grinding or wobbling, it needs to be replaced (about $300 to order the part and do it yourself). If not, you can just replace the sealing ring. The sealing ring is a $6 part. I gently pried out the old sealing ring (located between the shaft and the way water pump. Note that the hollow ridge and visible spring face outward on this part. Be sure to fully seat the ring with a dull object.

Reassemble and you should have a properly functioning raw water pump. An inefficient water pump can cause excessive engine temps and manifest itself through excess steam passing through the exhaust manifolds, not to mention the drips. I hope this article has helped you. I will also provide links to a great resource for ordering penta parts. I use them because of their great schematics and easy part search.