LD28 Raw water pump leak

[JeffScott92]

I have a steady drip coming from around the bottom bolt on my raw water pump. I pulled it apart and replaced the rubber gasket and impeller and it still has the same leak. The impeller I replaced was still in good shape. Do I just need to use a liquid gasket or do I have more problems? Temp. Gauge has been running about 10 degrees higher than usual the last couple of times out. I usually run about 160 and it is running about 170. No visible issues.

[tego]

Howdy Jeff, Since it's spring, I'd check very carefully to make sure you don't have a cracked housing on the pump. Barring that, it sounds like the main shaft seal might be leaking. How old is the pump? The front shaft seal is replaceable if you have the correct tools to do it. By the way, I'm glad to hear you kept your boat for another year. I'll be ordering my trailer next month. I want to get over to the Chesapeake the short way! Ben

[Isabel]

Running hotter is a concern. Could be various things but here are a couple of simple things to try. Start it up and observe and feel the hose leading to the mixing elbow on the riser on the manifold. If there appears to be a lot of back pressure, the mixing elbow is probably clogged. This happened on our boat with Nissan diesel. If you remove that hose at the mixing elbow and start it up with water running into a bucket you can see if you have a good flow or not. Even at idle you should not ba able to stop the flow putting your thumb over the hose. If there is constricted flow, it could be heat exchanger, raw water pump, or a clog some place. By working you rway upstream from the riser you should be able to figure it out. If the riser is clogged or something downstream of the pump, the back pressure could be the reason for the water pump leak.

The manifold risers on these engines usually fail at some point. They are designed in such a way that a failure could easily send water into the engine. We replaced ours and the design was much superior to the original. Can provide more details if needed. Good luck.

John VB

[eseyoung]

Did you solve this yet?

If you have an LD28 and you have the original mixing elbow you are asking for trouble.

When (not if) the elbow fails it floods the manifold. at that point the engine makes an excellent anchor...but not so much an engine.


Here is how fixed mine:
viewtopic.php?f=28&t=7011

viewtopic.php?f=4&t=7018

[JeffScott92]

Inspected everything. I think the water pump just needs a rebuilt. Ordered a rebuild kit for a little over $100, instead of buying a new pump for over $400. We shall see when the part get here.

[JeffScott92]

My rebuild didn't work. I think the casing may have been a little warped. Ended up having to buy a new one. Put it on today and pushed her hard for a short cruise. Temps are staying low.

[Panhdjoe]

Hey Jeff, I waved at you yesterday at Morris island. We were in our 19ft Grady White. Glad to see "Gina Baby" out and about. Have a great summer... Joe