Bravo 3 seawater pump air fitting delete.

[Leardriver]

I have an '07 496, engine OW660526, and I have the raw water pump off to put in a Hardin pump. I am looking at the air fittings for the fallible drain system, and wondering if I can unscrew them and put a pipe plug or similar in there, and take leaking out of the equation. I can reach the blue plugs easily enough to winterize the raw side of the closed cooled engine if I disable the air drain system.
Is there something fancy to screw in there, if so, what thread size? Plenty of people have done it, they just don't share their end results.

 

[alldodge]

Have read threads about blocking the ports but don't remember how? My comment is about the Hardin pump.

I have a Gen 1 and used it 2 seasons then put it on the shelf and never used it again. Reason is it's heavy and I had to hang upside down to install. So it is old guy and weight for reason

Last time I researched your style I found there is a difference between the Merc and Harden with impeller size. If it remains a slight size difference it's not a deal breaker, but just remember you may have to get all impellers from Hardin

 

[Leardriver]

The Hardin Gen 7 plus claims to use the common Merc impeller now.
I am 61, and hanging upside down in the bowels of my Chap 256 SSI on a hot day, donating all of my skin to sharp objects, was someone I want to do less of. That's why I am thinking about bullet-proofing the air fittings if such a solution exists.

 

[alldodge]

The write up is better, but note it uses Gen 2 to 4 impellers (47-59362T1) and not the Gen 7 (8M0104229)
https://www.hardin-marine.com/p-14525-replacement-impeller-for-mercury-oem-and-hardin-sea-pumps.aspx

https://www.mercruiserparts.com/bam/subassembly/31824/11414/210

All ok, just info

 

[Leardriver]

All finished. I worked about one hour per day for 3 days. It is 98 degrees in my man cave, and the old carcass can only sweat for so long.
I plugged the air fittings and the air intake tower that is built into the raw water pump. Any leak will have to be determined to escape.
The Hardin pump looks nice, I hope it works. I only get to boat about 3-4 days per year, so it should last a while.