www.iFourWinns.com
https://www.smwebhead.com/phpBB3/

AC Raw Water Pump Improperly Installed by the Factory
https://www.smwebhead.com/phpBB3/viewtopic.php?f=2&t=14816
Page 1 of 1

Author:  RD-Panama [ Tue May 03, 2016 12:02 pm ]
Post subject:  AC Raw Water Pump Improperly Installed by the Factory

My AC pump loses its prime when I put the boat back on the lift. I posted in the Vista forum last week asking if this was a common problem and how people deal with it. There were numerous replies and it seems to be a common problem for trailered boats and boats kept on a lift. In the course of working through the problem here is what I learned. My pump is a labeled as a Dometic Model 336185. The pump is actually manufactured by March Pumps and is a LC-3CP-MD-115. These are certified ignition protected pumps. Here is what March says about these Series 3 pumps:

DESCRIPTION:
Series 3 are centrifugal magnetic drive pumps, eliminating the need for a shaft seal. Pumps are serviceable with a screwdriver. See the parts list for a breakdown of parts.
OPERATION:
Pumps are not self-priming, lack a suction lift, and thus require a flooded suction. Pumps cannot be run dry because the impeller requires the liquid being pumped for lubrication.

Their Installation Guide even has a diagram:
Image

The problem is that my pump was installed above the raw water strainer where the inlet is not flooded. Here is my installation:
Image

The pump will never prime installed like this and will probably run dry and burn itself up. My question: How can Four Winns not know this?

Author:  Jdpber [ Tue May 03, 2016 1:00 pm ]
Post subject:  Re: AC Raw Water Pump Improperly Installed by the Factory

i do not at all like the kink bend in that hose.

Author:  Jdpber [ Tue May 03, 2016 1:01 pm ]
Post subject:  Re: AC Raw Water Pump Improperly Installed by the Factory

you can add a prime valve so that you will not loose prime in line before the pump

Author:  TheDanceII [ Tue May 03, 2016 5:29 pm ]
Post subject:  Re: AC Raw Water Pump Improperly Installed by the Factory

You have a shut off valve that you could close before lifting the boat. That will prevent it from loosing the prime.
I have always been able to re-prime by simply running the boat on plane for a few minutes. The forward momentum will push water up to the pump and prime the system.
I never had a problem with any of my boats and the pump would never pump water until you starting running on plane.

Give it a try.

Author:  noexcuses [ Wed May 04, 2016 3:55 pm ]
Post subject:  Re: AC Raw Water Pump Improperly Installed by the Factory

Where is the pump relative to the boat's waterline? It should be below the waterline.

Page 1 of 1 All times are UTC - 6 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/