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How to build a winterization pump

I built this little pump kit to winterize my 3 air conditioning units, but I found it useful in winterizing the engines also. It’s a simple very DIY project. I built it out of all parts I had around the shop. It started out with a 5 gallon pail with a lid. I drilled 2 1inch holes in the lid for the hoses. Next I took a fresh water pump I had replaced on the boat, it didn’t make good pressure anymore but it was perfect for this job. I screwed the pump to the lid, then put a couple of pieces of pvc board for backers and tightened the screws into them. Some scraps of 1/2 hose one short to the bottom of the bucket, one long to hook to the discharge on the air conditioner. This worked perfectly for 2 of my discharges, one I made an adapter of another short piece of hose. The wiring was really simple, a length of old 16x2, an on off switch in the middle, I stripped back the jacket and spliced in the switch just on the positive. The power end I put some 3/8” eyelets to hook to a battery, however I found I could use my jump box which was WAY lighter than a battery.

To use, simply pour some antifreeze of your choice into the bucket, fit the hose into the discharge of the air conditioning, then turn the pump on til antifreeze comes out the intake on the bottom of the boat. I also used it to winterize my closed cooled engines and generator. I filled the pail with antifreeze, removed the cap on the strainer, put the hose in the strainer. Then start the engine, and quickly turn on the pump. This is where the long cord I put on the pump came in handy.

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