Graco Heat /AC raw water pump.

[Capt. Rodbone]

We’ve used the heat and AC unit over the past two days but this morning shortly upon turning it on I heard a vibration. I went below and determined it was coming from the raw water pump. I shut the valve off and attempted to take the butterfly nut holding the strainer in place off so I could clean the strainer. That has been a challenge I ultimately decided to not force until I could get some opinions. No telling how long it’s been since it has been removed but I can barely budge it. I’ve sprayed it with W 40, I’ve used vicegrips I’ve tapped on it numerous times with a hammer. No Joy. I do see it appears to be shifting down but I would have expected it to come straight off once the nut is loose? Maybe I’m wrong. Should I keep tapping and trying to dislodge this? Pictures below may help.

 

[Lepke]

Too much pressure on the nut wings may break them off. I'd use a larger vice grip or channel locks to grab the center from the side to apply some torque.

 

[Cigatoo]

Water pump pliers / channel locks. After you are sure that the seacock is shut off.

 

[C lectric]

Can you make a tool to contact/grab both ears of the nut close to the hub.
Don't use the ears for leverage. THe closer to the hub you can turn on the less likely to break an ear.


Tried some heat from a propane torch? It may not take a lot as you will be heating the exterior of the nut and expanding the nut exterior.

Once moving it likely will be MUCH easier to finish.

And yes, is the seacock OFF?

Once off I think I would drill a small hole in the very top so some penetrating oil can be applied in the future.

 

[Capt. Rodbone]

Great points all around.

I will pick up a butane torch tomorrow to do just that. I probably have some larger channel locks or vice grips that will work however the handle needs to be short because of a stringer separating that part of the bilge from where my port engine is. A few kind responses have asked me to confirm the thru hull is closed and it definitely is. My question in the original post is once this starts loosening up will it continue to shift downward or should it pull straight out?

 

[tiltrider1]

I will pick up a butane torch tomorrow to do just that. I probably have some larger channel locks or vice grips that will work however the handle needs to be short because of a stringer separating that part of the bilge from where my port engine is. A few kind responses have asked me to confirm the thru hull is closed and it definitely is. My question in the original post is once this starts loosening up will it continue to shift downward or should it pull straight out?

I would use Map Gas. You can get it at Home Depo. Burns hotter than propane or butane. Not nearly as hot as acetylene.