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A/C raw water pump

Posted: March 24th, 2021, 4:50 pm
by tonyiiiafl
I have teh original A/C pump circa 1994. Work great but i know the days are limited How big a pump is needed or do you have for twin units, a 12K and a 16K? Both run off the same raw water. Pump

Re: A/C raw water pump

Posted: March 24th, 2021, 5:03 pm
by Midnightsun

Re: A/C raw water pump

Posted: March 24th, 2021, 6:28 pm
by bud37
How many GPH is the pump that is there now ? If it works properly then just replace with the same whatever that is...if it is not working efficiently then an upgrade would be wise.... be aware in this case, more is not better as in heat exchangers the important thing is contact time to transfer heat...it can be over done.

Re: A/C raw water pump

Posted: March 24th, 2021, 7:50 pm
by tonyiiiafl
It is pretty rusted and the tag is gone. I am going to look through the line ticket and see if there is any I’d on it. Yes, volume is not always the good thing. I had an original fresh water pump go last year and it delayed a week away. If this pump goes I want a spare on hand, like I carry a starter, alternator and belts

Re: A/C raw water pump

Posted: March 24th, 2021, 8:22 pm
by bud37
Thats too bad the tag is gone.....I wasn't saying 750 gph was too much, I don't know, just saying try to get the spec matched up close. Could you post a pic of this pump, maybe someone would recognize it or have the same boat and be able to read the ID tag on theirs.
I like the idea of spares myself.

Re: A/C raw water pump

Posted: March 24th, 2021, 9:07 pm
by Viper
I suspect you have a black March pump in front of the port engine. What ever you do, make sure you get a unit that is ignition protected if you're putting it in the same location. Not all March pumps are ignition proof and I know that early boat builds used non ignition proof units. If they're not sealed and are vented to atmosphere, in other words you can see the motor windings, chances are it is not safe for a gasoline engine compartment. The Dometic red sealed water cooled pump is safe, I believe March has the same unit under their brand. They're sealed so if water gets splashed on it, it won't hurt it. Mount it below the water line as they should not run dry, the water is what cools them as the motor is not exposed to ambient air. The PML500 is probably all you need for two AC units as I've seen them on applications with 3 ACs.

Re: A/C raw water pump

Posted: March 25th, 2021, 6:03 pm
by tonyiiiafl
I do have that pump. I saw a few that were not mentioned if they were so when I asked the manufacturer, I got an “It is OK to use with A/C units”. I saw that one oat DEFENDER, and am looking at it. I am a stickler to see it meets SAE standards and is ignition protected. I saw an IWAKA at defender, but no mention or reply from manufacturer about ignition protection. Thanks!!!!!

Re: A/C raw water pump

Posted: March 26th, 2021, 9:41 am
by buster53
Ok, I’m guessing you have a Carver 390, which turned into a 400 then 404, which is the same boat as the 355, then 356, but without a cockpit. All have 12k and 16k AC units. They probably all use the same pump. If I was at my boat, I’d take a look, but I’m sure someone who has one of these models will chime in.

Re: A/C raw water pump

Posted: March 27th, 2021, 6:40 pm
by tonyiiiafl
Here we are. It is a March 1050GPH pump. I was wondering if anyone ever used a KoolAir PM1000? It is the same that WEBASTO sells under their label. It is about $100.00 less than a March.
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Re: A/C raw water pump

Posted: March 27th, 2021, 6:44 pm
by Midnightsun
Thats really overkill, a 750 or so is plenty for your application.