Fresh Water (Coolant) Impeller?

[SkuffedKeel]

Hello again!

I'm still learning the ins and outs of my 2004 Catalina 350 (first boat) and I've been making sure to keep up with the engine maintenance. This past weekend I did my 100 hour oil/filter and transmission fluid changeout and raw water system inspection including the raw water impeller on the front (salon side) of the engine. Nothing needed to be replaced there, but I mentioned everything I did to my Dad and he seems to think there should be a fresh water (coolant) impeller that needs inspection and replacement. I can't seem to find anything about this in what I've read so far and as I've been working around the engine I haven't seen anything obvious. Am I missing something?

[KenKrawford]

The image below shows the location of the raw water pump. Unfortunately the bolts that have to come off in order to inspect or replace the impeller are facing aftward. You may also have to loosen one or both hose clamps in order to work on the pump. If any of the vanes on the impeller are missing then the it needs replacement. It's also important to find any missing impeller vanes. They may be in the elbow on the discharge end of the pump or in the heat exchanger.
Also, don't forget to close the raw water thru hull (located near the port aft area of the engine) before taking the pump faceplate off. You can access it by removing the "shelf" above the engine in the aft cabin or underneath the mattress access panels. Be sure to open it after you're finished or you'll be repeating the job again real soon!

m35b eng.jpg (151.34 KiB) Viewed 486 times

[wolfe10]

No need to "inspect" the engine coolant pump (driven by the belt). Yes, the raw water pump impeller does need inspection/replacement every couple of years unless high engine usage suggests more often.

Do make sure the engine coolant pump is not leaking-- no different than on any vehicle.

And, yes, changing the coolant every couple of years (no different than any vehicle) is just good preventive maintenance.

[SkuffedKeel]

The image below shows the location of the raw water pump. Unfortunately the bolts that have to come off in order to inspect or replace the impeller are facing aftward. You may also have to loosen one or both hose clamps in order to work on the pump. If any of the vanes on the impeller are missing then the it needs replacement. It's also important to find any missing impeller vanes. They may be in the elbow on the discharge end of the pump or in the heat exchanger.
Also, don't forget to close the raw water thru hull (located near the port aft area of the engine) before taking the pump faceplate off. You can access it by removing the "shelf" above the engine in the aft cabin or underneath the mattress access panels. Be sure to open it after you're finished or you'll be repeating the job again real soon!
m35b eng.jpg

Thank you Ken! In this case it was the fresh water (coolant) system I was concerned about. The raw water side I had figured out although I must have some sort of aftermarket system because mine looks different than stock and is actually really easy to access and inspect the impeller.

SVSenja_Engine.jpg (119.59 KiB) Viewed 481 times

[SkuffedKeel]

No need to "inspect" the engine coolant pump (driven by the belt). Yes, the raw water pump impeller does need inspection/replacement every couple of years unless high engine usage suggests more often.

Do make sure the engine coolant pump is not leaking-- no different than on any vehicle.

And, yes, changing the coolant every couple of years (no different than any vehicle) is just good preventive maintenance.

Thank you Brett, this is the info I was looking for and I appreciate your response!