C-28 Shower sump + transducer

[GraemeC]

Hi. I am hoping you can help me solve an over-crowding problem. I posted this to the general discussion board but no-one has been able to help, despite a lot of views. Either everyone is perplexed or it's obvious or I posted it in the wrong place!

The cavity at the foot of the steps [outside the door to the head] in my C-28 is the site for both the [Rule] shower sump box and the transducer for the depth sounder. The space isn't big enough for both of them -- the transducer has been dislodged so no depth gauge. I am in the process of trying to re-attach it but, frankly, one of them has got to go.

Perhaps you could tell me, when a C-28 (circa 2014) leaves the factory what is the design for handling the shower water and where is the transducer fitted?

Thanks,

GraemeC

 

[BB marine]

Yes it sounds like shower sump and transducer is in the right place. It is a tight location and a pain to work on but it can be done. The transducer sounds like it was an epoxy install. I would change it to a wet install using Base and o-ring kit 33-268-01. The base is installed to the hull using a marine sealant. Once the base is installed, sealant cured, the base is filled with propylene glycol and the transducer is installed to the base with a o-ring for a seal. If you google AirMar 33-268-01 and look at the parts you will see it is an easy fix.

 

[trailertrawlerkismet]

We have an R29S with the sump pump located under a floor board outside of the head in the stateroom, just like yours. In our case the transducer is located at the stern of the boat, on the port side, back by the rudder controls. I've just replaced the sump (cracked fitting) so I've spent some time in the small space. You asked what is the design for the shower water. Our shower drains into the sump. We also have 2 A/C units, each has a drain hose into the sump. Lastly there is a drain hose to discharge water collected in the sump tray that discharges the water to the starboard side of the boat….on our R29S. Have someone pour water into the shower drain while you observe the starboard side vents and you'll see where it discharges.

If you're thinking of moving something my guess is it may be easier to move the transducer then the sump pump, as the sump pump has at least 2 hoses, 1 additional for each A/C…if you have A/C, whereas the transducer only has 1 line. I's suggest calling the factory to get there advice on where to relocate your transducer on your Cutwater and how/where to run the line.

Jim F

 

[Cutwater28GG]

just note that a stern mounted transducer suffers from poor performance at speed with an inboard engine as the prop causes bubbles in the water flow. thats why we have an in hull transducer

 

[Cutwater28GG]

mine (incorrect install as its a 2012) was epoxied to the hull in the same location as yours. seems there is enough space around the unit?

is your sump pump in the wrong place?

 

[GraemeC]

Thanks to all for the replies. I appreciate people taking the time.

I have looked at shifting the transducer but the spot there is ideal -- well forward and a flat part of the hull.

I think my problem may be that the shower sump box is a replacement for the originally installed model as it looks to me like it is too tall for the space. It is a Rule box, and I wonder if anyone else has that brand, or was a different brand installed? I have trawled the internet trying to find something with smaller dimensions but maybe I am missing something.

Thanks again,

GraemeC

 

[GraemeC]

... and I will definitely be doing the wet install. Thanks for the heads up.

G

 

[trailertrawlerkismet]

just note that a stern mounted transducer suffers from poor performance at speed with an inboard engine as the prop causes bubbles in the water flow. thats why we have an in hull transducer

This makes sense and I would guess the best transducer location is or can also be based on how fast a boat can travel. Our R29S doesn't have the top speed of a Cutwater, maybe thats why our transducer is in the stern of the boat? There must be some formula about best transducer locations, based on speed, prop size etc.

Good luck on your reinstall.

Jim

 

[Cutwater28GG]

Im not an expert but have been doing some research recently on transducers as I have for some reason two on my boat. from what I can tell even at low speed with an inboard there is air in the water so a transom mount can suffer performance.
question: does your bottom depth drop out at any speed/depth? if not then its fine.
if you fish, you may also be suffering from poorer fish traces when trawling etc..

for planing boats order of preference

pocket thru hull
thru hull
in hull (what older rangers are fitted with the P79 Airmar for instance)
transom mount

for those of you who have the new shiny 7612xsv plotters with Chirp; what transducer are you using? transom mount of in hull or a combo? what model are they?

 

[BB marine]

I'm not sure a transom mount or aft mount on a Cutwater will work that well if you want it for cruising. A step hull causes air under the hull. Recommended location would be forward of the step. Hi Performance step hulls get enough hull lift to completely lift the forward step out of the water and rear mounted transducer work. The Cutwater doesn't go fast enough to do this unless you have a 30 Cutwater outboard. I have a non chirp P79 installed by Cutwater and have a 7612 XSV plotter. If you do mount a transom mount or a aft bottom mount for trolling it should be mounted on the starboard side to get a way from the pressure wave on the port side aft of the boat caused from the right hand rotating prop.