Marinette Boat Forum

NEWMAR

https://dcpoweronboard.com/galvanic-isolators/

Galvanic Isolators

Here is a means to significant savings in boat haul-out fees and zinc replacement costs.

Sacrificial zincs corrode away as they protect metal thru-hulls, shafts and props from damaging electrolysis. Stray, low-voltage current flowing between the AC safety ground and DC bonding system is a principal cause of this "galvanic" action.

Install a Galvanic Isolator between the AC safety ground and DC bonding system to block a majority of the low voltage currents and corrosive action on the zincs. Such current flow and corrosion activity is significantly reduced while the integrity of the critical safety ground path is maintained.

For additional safety, these units feature a large capacitor, providing a secondary low impedance path for sending AC current to ground.

Shore Power VAC, Hz Rated - 115/230, 50-60.

Select these isolators by Amp rating - either 30A or 50A.

Mfg. No. Shore Power
Amp Rating Dimensions
Height x Width x Depth Weight
GI-30 30 2.7" x 4.8" x 7.3"
(69 x 122 x 185mm) 2.45 Lbs
(1.1 kg)
GI-50 50 4.5" x 4.7" x 8.9"
(114 x 119 x 226mm) 3.2 Lbs
(1.5 kg)
SKU Model QTY
00017448 Mfg# GI-30 Price: $168.00
00017445 Mfg# GI-50 Price: $198.40
View Cart

bill

What would cause pits in the hull? inside and out? 1973 32' FB express - twin 318 = steel rudders

Ok, Well the pits inside that I have found are up in the bow by the float and bilge pump. Still need to investigate the engine room.

your bilge pump is leaking DC current.
is your forward bilge dry
check your wire connections ensure they are waterproof
float switches are a common source of DC leaks

I just bought this '73 32' FB express. I was in the water at my marina when I bought it. The boat is still on shore now and dry. I have almost completed the bottom paint. Complete grind to bare metal and 5 coat Interlux system. But, I remember one day I went to look at her prior to purchase and the bilge was holding water. and it had a stale film on top. I got in the v-birth and could not get the pump to kick on. The owners live 3 hours from the marina. When the owners got on board, I went to visit and the three of us got in the v-birth and the pump kicked on and water pumped out. But, to answer your question about the forward bilge being dry....I would have to say NO. I am in the process of completely cleaning and disinfecting this boat as it was a "mildew fest" inside. While I am cleaning the bilge I find these pits. Now last night I found a very concerning deep pit. I will check the wires to the float and bilge and see what I can figure out as far as waterproof connections go. NOW, I need the proper way to fill in a deep pit.....? Alumiweld, JB Weld? something like that work?

I'd suggest PC-11. It's the water proof version of PC-7. I used it on the bottom after a complete sand blasting and 1 coat of 2 part epoxy primter. The PC-11 has held superbly without any issue. After applying the PC-11 to fill in the pitting, applied another 3 coats of 2 part primber and 2 coats of Interlux's Trilux 33. That was 3 seasons ago. Redid just the Trilux 33 bottom paint this season (sand down to ruff up and 2 coats - 1 white - 1 black).

Bill

If the boat's on the hard, where is the water entering the fwd bilge? That's usually a dry area or at least drier than the aft bilge. Is the deck leaking? And if so, it should not be so much that the fwd bilge pump can't handle it. Locate the water intrusion. And check other wiring running thru the area such as nav lights, etc.

Bill, Everyone speaks of the quicksilver G.I. but they are getting hard to track down and quite expensive. I just recvd. My newmar unit that I chose instead and have to say after doing a diode check and ohm out plus a little peak inside it is a well built unit and I don't see any reason it won't do just as good of a job. Thx.