Winterizing the A/C system
- denpooch
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Winterizing the A/C system
I would like to find out how you folks are winterizing the A/C system.
I know that if I remove the cover of the raw water strainer to add antifreeze. I will lose the prime and the process becomes a real pain.
I have a friend at the dock who tells me that he has a raw water strainer cover that has a female hose fitting incorporated into the cast. He states that this allows him to flush the system first with fresh water and then introduce antifreeze, all without losing the prime.
Unfortunately I was not able to view this 'thingamajig' before he pulled his boat for the season.
I have never heard of this and the local marine supplier has not as well.
I am interested in how you guys are going about this task.
I know that if I remove the cover of the raw water strainer to add antifreeze. I will lose the prime and the process becomes a real pain.
I have a friend at the dock who tells me that he has a raw water strainer cover that has a female hose fitting incorporated into the cast. He states that this allows him to flush the system first with fresh water and then introduce antifreeze, all without losing the prime.
Unfortunately I was not able to view this 'thingamajig' before he pulled his boat for the season.
I have never heard of this and the local marine supplier has not as well.
I am interested in how you guys are going about this task.
- buster53
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Re: Winterizing the A/C system
I have a couple of them on my boat. A company used to make them but went out of business. If I can figure out how to post a photo, I will this weekend. You can probably make them yourself. They look very basic.
- bud37
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Re: Winterizing the A/C system
It gets even more interesting when the pump shuts off in our boats as the system drains back from up top.
What I have been doing is removing the hose from the thru hull, vac out the water from the strainer, put the lid back on and holding the hose up higher than the pump with a tall funnel, fill everything and start the pump and keep filling until comes out the the hull then let the pump cavitate a bit and shut down and be prepared for the back flow.....just goes in the bilge......stick hose back on thru hull, then open the thru hull when boat comes out.
Sounds complicated huh, but really only a few minutes.that is because I like to do it before the boat comes out ( access to 120v power is sometimes an issue.
You can pump it thru from the outside drain as well after the boat is out.
What I have been doing is removing the hose from the thru hull, vac out the water from the strainer, put the lid back on and holding the hose up higher than the pump with a tall funnel, fill everything and start the pump and keep filling until comes out the the hull then let the pump cavitate a bit and shut down and be prepared for the back flow.....just goes in the bilge......stick hose back on thru hull, then open the thru hull when boat comes out.
Sounds complicated huh, but really only a few minutes.that is because I like to do it before the boat comes out ( access to 120v power is sometimes an issue.
You can pump it thru from the outside drain as well after the boat is out.
FWIW.....The above is just my opinion.
- tomschauer
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- Midnightsun
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Re: Winterizing the A/C system
This will give you a good idea of what it looks like. Simply remove the cap of the strainer and replace with this. I then connect a large hose from the adapter into the bottom of a bucket I have set up just for this purpose. Mine are custom made to suit my application. Key here is to set yourself up well so everything is a piece of cake when you winterize. First year takes quite some thought and work but the following years all is good.


- denpooch
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Re: Winterizing the A/C system
Hans are those a press fit or screwed into the strainer? I don't believe the Algonquin strainers on my boat are threaded.
Bud don't you lose the prime once the caps are removed? I think if I did that the pump would simply run dry. Are you 'forcing' the water past the impeller of the pump to prime?
Thank guys.
Bud don't you lose the prime once the caps are removed? I think if I did that the pump would simply run dry. Are you 'forcing' the water past the impeller of the pump to prime?
Thank guys.
- Midnightsun
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- Midnightsun
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Re: Winterizing the A/C system
You should never lose prime if they were installed properly from the factory which is not always the case. It is as simple as having the strainer and pump below the water line. In this configuration you will not need to prime ever as long as the boat is in the water. Same goes for using the cap. Take a look at the video in the seaflush link a couple of posts above, as long as the seacock is closed while winterizing via the cap you should not lose or need to prime.