7.4 Bravo Three Water Pump Freeze Damaged?

[orcahead]

I have a Mercruiser 7.4L Bravo Three sterndrive. It's in a 1994 Searay Bowrider and it's never had the impeller replaced. We had an early freeze here in Seattle a few weeks back and I hadn't been able to winterize it. I tried to keep the block warm, and I tried to start it and get antifreeze into the coolant water, but I wasn't seeing any water coming out of the cooling system so I stopped.

I tried again now that it's warm it's still not putting out any water. I ran it for a couple minutes to warm it up to 130F, but nothing comes out. The pump pulley is definately turning. I don't really feel any liquids in the hoses. My fear is that there was still ice in the water pump and the impeller / pump broke.

Is there any further diagnosis I can do before I have it fixed? Is this something that I could do myself, or does the engine have to come out?

I'm going to have to get it towed to a service center because it lives on the lake and doesn't have a trailer. Any ideas how much a couple mile tow and replacing the impeller / water pump should cost?

While I have it in the dealer is there other major maintenance that I should have them do? I do all the engine and drive oil changes.

 

[Don S]

Re: 7.4 Bravo Three Water Pump Freeze Damaged?

The fact that it's a 94 and the original impeller is about all the troubleshooting you need to do before you replace the impeller.

There are lots of maintenance items that need done. Look in any owners or service manual.

http://www.boatfix.com/merc/Owner/gas/86017101.pdf

Here is one for an example. It's a 2000, but you will get the idea, gear lube change, ujoint lube, gimbal bearings , alighment, tuneups, oil changes, fuel filter changes. All sorts of things.

I can't say if you can change it, ell, I don't even know if you know a screwdriver from a wrench. Plus, I have no idea the access in your boat.