Removing Thruster Zincs

[SeaworthyTwo]

I am replacing the zincs on bow and stern thrusters on my R-25. With the help of PB B
laster, I have removed the bolts from each thruster zinc but the zincs themselves are crusted on the the thruster prop housing. I am letting them marinate in PB Blaster oil overnight to see if that helps. Any suggestions about how to get the old zincs off would be appreciated. I am planning to launch her on 6/19. Thanks.

 

[rpmerrill]

Mine were pretty well crusted in place also. I think I used a little fine pointed flat bladed screw driver and a miniature pair of channel locks to pry them loose. I came to the job loaded for bear, but it wasn't a problem. The little splined end of the prop shaft popped up nice and clean. Maybe a little wire brushing was all it took.

Thinking now, I'm wondering if some sort of anti-seize would have been in order before the new zinc went in place?????

 

[Cessna172]

I used a small-size plumber's wrench to reach in grab the zinc and spin it off. Worked great!

 

[Connerkip]

I agree with the plumber wrench use. Works great.

Home Depot, $12.
11 in. Reach 3/8-1 in. Basin Wrench

 

[SeaworthyTwo]

Thanks to all. I'm on it.

Rich, see you when I'm back from ME.

Charlie

 

[rpmerrill]

Charlie,
Sorry for not getting in touch in June, b4 you went north. Grandkid visits and a nasty bout with sciatica kept my busy.
r

 

[knotflying]

Try a plumbers basin wrench. In the past I have also been able to hit it wit a long shank flat screwdriver and that has worked. I now apply a small bit of marine anti- seize to the small hole and it seems to work well for removal.

 

[baz]

It's important to maintain the anodes on the thrusters. They are small and in some waters can be eaten away quickly. If they are allowed to be consumed to zero then the metal in the thrusters can be compromised leading to a very expensive repair task. The first part of the thruster that would be compromised are the threads that the anode holding bolt engages. Once these threads become eaten/worn there's nothing for the anode bolt to engage securely.

 

[ALICE J]

I have used a copper based anti seize on the threads, my thinking being that I don't want to compromise the electrical bond of the zinc to the thruster base.

 

[SeaworthyTwo]

Thanks to all who responded. Off with the old and on with the new. Ready to launch.

 

[rpmerrill]

I just came back home from looking at my spare set of thruster zincs.
Not sure where I came up with the "splined ends" idea. They are just plain round shafts.
I stand by all the rest.

 

[RichBirk]

I realize this is an old thread but I just discovered my favorite way to remove these seized on anodes.

After spraying with PB Blaster and letting them sit overnight, I tried a pair of nippers used for triming horse hooves. Popped right off. After a quick clean-up with a wire brush, reinstalled with a drop of blue thread locker on the screw.