Raw Water Breaker. Where's the wire go?

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Newtrawlerowner

Newtrawlerowner

Senior Member
Joined
Nov 16, 2019
Messages
326
Location
USA
Vessel Name
PartnerShip II
Vessel Make
2003 Mainship 400
I have a 2003 MS 400 and am trying to find the end point of the Raw Water wire. There is a breaker labeled same but no noise when I flip it on. Wondering where others may have found the other end.
 
It may be for a raw water wash down pump. On my Pilot 34, the only outlet for that pump is in the anchor locker. You may be able to track down the pump, if there is one, by looking for the thru hull and seacock for same.

Happy hunting,

Brett
 
Do you have a manual for the boat.
The later model 40T manual is available online and guessing they are very similar.
From my Bacchus website go to the Useful Links section where you will find one for MS Manuals.
MS usually shows at least an arrangement Dwg that shows the general location.
IMO it us important to k is where all the through hulls are located and what they are for in case of an emergency and need to shut them off... not to mention operating them periodically to know they operate freely. MS did a good job of labeling components and should bdceady to find the thru hull. Then follow the raw water piping to the pump and check for power with breaker on. There may / may not be an inline fuse near the pump.
Hope that helps.
 
Bacchus said:
Do you have a manual for the boat.
The later model 40T manual is available online and guessing they are very similar.
From my Bacchus website go to the Useful Links section where you will find one for MS Manuals.
MS usually shows at least an arrangement Dwg that shows the general location.
IMO it us important to k is where all the through hulls are located and what they are for in case of an emergency and need to shut them off... not to mention operating them periodically to know they operate freely. MS did a good job of labeling components and should bdceady to find the thru hull. Then follow the raw water piping to the pump and check for power with breaker on. There may / may not be an inline fuse near the pump.
Hope that helps.
Click to expand...

If he is not hearing a hum anywhere on an otherwise silent boat, my guess is the pump is dead or not installed. It certainly should not be hard to find if there is a through hull for it. Mine was installed right next to the potable water pump on the aft bulkhead in the engine compartment. Out of habit, I keep wanting to call mine the "ER," but if you can't get your body in there and close the lid behind you, it just isn't an engine room. :eek:
 
You could have an accumulator tank. The pump will only run when the pressure created by a low accumulator triggers it.

Turn on the breaker and turn on a faucet and listen for the pump.
 
Bacchus said:
Do you have a manual for the boat.
The later model 40T manual is available online and guessing they are very similar.
From my Bacchus website go to the Useful Links section where you will find one for MS Manuals.
MS usually shows at least an arrangement Dwg that shows the general location.
IMO it us important to k is where all the through hulls are located and what they are for in case of an emergency and need to shut them off... not to mention operating them periodically to know they operate freely. MS did a good job of labeling components and should bdceady to find the thru hull. Then follow the raw water piping to the pump and check for power with breaker on. There may / may not be an inline fuse near the pump.
Hope that helps.
Click to expand...

If he is not hearing a hum anywhere on an otherwise silent boat, my guess is the pump is dead or not installed. It certainly should not be hard to find if there is a through hull for it. Mine was installed right next to the potable water pump on the aft bulkhead in the engine compartment. Out of habit, I keep wanting to call mine the "ER," but if you can't get your body in there and close the lid behind you, it just isn't an engine room. :eek:
 
Our 430 has an aft stereo breaker but there is no stereo. My wiring diagram shows a raw water pump but there is no breaker on the panel for one. The diagram also shows the port battery powering the circuit for the upper helm. It's actually powered by the starboard battery. Mainships information is a little sketchy.
 
A raw water washdown should be easy to locate. If the hose bib/faucet is closed and/or the seacock is closed the washdown is a pressure pump may not be actuating.
 
Newtralwerowner: Firstly, I would like to confirm you actually have the MS400 vs the 390. To my knowledge, the 400 was first made in 2004, but some 390's also seem to also have the 2004 build date. I think MS shifted over from the 390 to the 400 in 2004.

I have not seen anyone else with a 2003 MS400, but I suppose it's possible. I just want to confirm it so we can make sure we are answering your questions for the correct model, as the 390 and 400 have significant differences. You can verify the year by looking at the HIN number on the transom. I believe the last two digits indicate the year. Others may chime in if I am wrong about this.

Having said that, if you really have the 400 I probably have the answer to your question. That switch is for the raw water washdown pump which was an option on this model. I have the switch too, but not the pump. Take a look in the anchor locker for a spigot or water hose connection of some kind. If you don't see one, that means your boat wasn't built with that option.

Ignore this answer if you actually have a 2003 MS390, as I am unfamiliar with that model!
 
menzies said:
You could have an accumulator tank. The pump will only run when the pressure created by a low accumulator triggers it.

Turn on the breaker and turn on a faucet and listen for the pump.
Click to expand...

Ah, I didn't read raw water, my bad!
 
Raw Water Breaker

garmstro55 said:
Newtralwerowner: Firstly, I would like to confirm you actually have the MS400 vs the 390. To my knowledge, the 400 was first made in 2004, but some 390's also seem to also have the 2004 build date. I think MS shifted over from the 390 to the 400 in 2004.

I have not seen anyone else with a 2003 MS400, but I suppose it's possible. I just want to confirm it so we can make sure we are answering your questions for the correct model, as the 390 and 400 have significant differences. You can verify the year by looking at the HIN number on the transom. I believe the last two digits indicate the year. Others may chime in if I am wrong about this.

Having said that, if you really have the 400 I probably have the answer to your question. That switch is for the raw water washdown pump which was an option on this model. I have the switch too, but not the pump. Take a look in the anchor locker for a spigot or water hose connection of some kind. If you don't see one, that means your boat wasn't built with that option.

Ignore this answer if you actually have a 2003 MS390, as I am unfamiliar with that model!
Click to expand...

To answer the 1st concern, yes this is a MS 400. I'm not near the boat otherwise I'd take a picture of the emblem on the outside of the main salon. The sales receipt shows a 2003 MS400 and the last 2 digits on the H.I.N are 03.

I've looked in the obvious places and studied the owners manual wiring diagram. It shows a wash down pump and thru-hull on the port side at the engine room forward bulkhead. It isn't there.
I've also looked in the anchor locker. Not there either.
My question is of those MS owners regardless of year that have a Raw Water breaker on the 12 volt panel, where does the wire end up if they in fact do have a raw water pump? Regardless of what its used for.
Also has anyone "T"ed off another thru hull to accommodate another use? I could do that easily with the macerator as I doubt I'll ever use that for emptying the holding tank.
 
A RW washdown may very well have been an option vs stbd equip. If no plumbing, outlet in / near anchor locker likely none was ever installed.
Factory may have installed but not wired a breaker. Have you looked at the back side to see if its output is even connected? I have 1 or 2 breakers on my 34HT that were never wired.
If wired but no plumbing or pump installed I'd check the area indicated on schematics. Is there any wires not connected? Or possible PO installed accys? Likely the wiring harnesses were std for a boat and not customized for options selected / not selected but surprised if it was connected & left potentially hot! I'd venture a guess that stranger things have happened.
I wouldn't anticipate any issue with aT into the macerator discharge. I T'd into a raw water head supply on last boat to supply a RW wash down and never had a problem. I did install a 3 way valve and switched as needed but would venture a guess that it would have worked fine w/o the valve.
 
Our Mainship 400 washdown pump is in the engine area fwd Port side wall.(single engine) ..the pump will turn on when the pressure drops, meaning if you try to spray the anchor the pump turns on...provided the breaker is closed.(to be honest I have had to tap on it a few times,,,it probably need to be given some attention)
 
jefndeb said:
Our Mainship 400 washdown pump is in the engine area fwd Port side wall.(single engine) ..the pump will turn on when the pressure drops, meaning if you try to spray the anchor the pump turns on...provided the breaker is closed.(to be honest I have had to tap on it a few times,,,it probably need to be given some attention)
Click to expand...


If you have a chance, would you take a picture of the pump and the wash-down hose at the anchor?
I'm going to install one and am curious where to put everything. Thanks in advance.
 
Bacchus said:
A RW washdown may very well have been an option vs stbd equip. If no plumbing, outlet in / near anchor locker likely none was ever installed.
Factory may have installed but not wired a breaker. Have you looked at the back side to see if its output is even connected? I have 1 or 2 breakers on my 34HT that were never wired.
If wired but no plumbing or pump installed I'd check the area indicated on schematics. Is there any wires not connected? Or possible PO installed accys? Likely the wiring harnesses were std for a boat and not customized for options selected / not selected but surprised if it was connected & left potentially hot! I'd venture a guess that stranger things have happened.
I wouldn't anticipate any issue with aT into the macerator discharge. I T'd into a raw water head supply on last boat to supply a RW wash down and never had a problem. I did install a 3 way valve and switched as needed but would venture a guess that it would have worked fine w/o the valve.
Click to expand...


I'll be sure to pull the panel and look. Thanks for the suggestion about wiring and water connections.
 
Here's the requested picture of our raw water strainer and pump... IMG_20200627_183901.jpeg
 
My MS 400 did NOT have a raw water pump. I did find the wire in the wire run on the port side in the engine room. The wire was labeled as per the owners manual wiring diagram. The diagram showed a raw water pump roughly in that location so looking in that area seemed logical.
 
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