Understanding the CAPAC

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carl
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Understanding the CAPAC

Postby carl » Mon Feb 06, 2017 10:36 am

Looking for an understanding of my CAPAC system. This is one system I have not yet traced out but I fully intend on getting an education about it as I need to fully understand the system. By reading through the many posts on this forum I picked up on the CAPAC may be a through hull. This was not explained, it was more hinted at in a casual comment (I think it was on a comment about painting the bottom of a Marinette and making sure you didn't paint over the CAPAC transducer or sensor or something like that). So what can you guys tell me about my CAPAC system? First I would really like to know if it is in fact a through hull transducer or sensor of some type? When I push the button on my CAPAC meter it seems to be working okay but what am I actually looking for? Additionally I was wondering if my CAPAC system is connected to my DC or AC electrical system or is it a stand alone system that doesn't need power to operate? I was very fortunate when I bought my boat as it had most of the original owners manuals onboard but nothing on the CAPAC. My boat is a 1990 and if someone has the original owners manual from that year or close it would be truly great if you could scan it and get it on this forum. I've searched the web high and low and cannot find anything about this CAPAC system, they must be out of business for a long time now. Looking forward to your replies and as always the dialogue here has been great, very informative and much appreciated.
1990 Marinette 32' Sedan Fly Bridge "IKOI"
Twin Crusader 350's (Closed Loop Cooling)
Bow to Stern Full On Restoration in Progress
Chickamauga Lake, Tennessee
A boat is always safe at shore, but that's not what its built for...

jralbert
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Re: Understanding the CAPAC

Postby jralbert » Mon Feb 06, 2017 11:04 am

Carl..I'll attempt this but I can't conjure up all the tech detail. Yes, it''s a thru hull, usually mounted (at least it was in the '88 FBS model I had and others where the helm was port side) aft of mid=-ships on the port side. It measure the electrical potential of the hull using a silver/silver chloride metal detection plate on the water side. I believe it's grounded to the hull inside and is not connected to the ship's electrical system. You can't switch it on/off. Pressing the button on the readout panel closes a circuit and causes the needle to register the potential. For our hulls, the proper range is marked on the instrument.

Silver/silver chloride plate is quite thin and delicate so never scrub it down with anything tougher than a sponge (lightly please) and don't paint it because paint interferes with its contact with the water, rendering it useless.

I will try to find my manual and post it. Stay tuned. The other good news is that the company survived but I don't remember the successor name - it was posted here a long time ago. They primarily make units for big ships, including spendy aluminum yachts, but parts for the original Capac may be available in some form. It's an important tool to keep the hull safe from deterioration.

UPDATE: I COULD NOT UPLOAD THE CAPAC PDF FILE. SITE SAYS IT DOESN"T RECOGNIZE THE PDF FORMAT> ADMIN????
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

EWRice
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Re: Understanding the CAPAC

Postby EWRice » Mon Feb 06, 2017 11:34 am

My understanding of the CAPAC system is as follows:
All you are doing is measuring the voltage your boat creates by being in the water. The gauge reads milivolts and the button just completes the circuit to the gauge. The circuit is separate from your AC or DC system. It reads DC volts.

One lead from the meter is connected to the hull, usually a stringer near the engines. The other lead is connected to a special insulated thru hull on the port side, about midship, just up from the keel. Kind of looks like a 8" or so dinner plate with a 2" metal disc in the middle. The plastic insulator "the plate" can be painted. The metal disc cannot. Don't scrape it, blast it or any other abrasive as it has a silver coating.

The short of it is the lake is the battery electrolyte and your boat is one of the plates inside the battery. A certain amount of current is good. Go beyond that and you have problems.
Muskegon Lake
1972 32' Express flybridge
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson

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carl
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Re: Understanding the CAPAC

Postby carl » Mon Feb 06, 2017 11:47 am

I figured with the switch being a momentary push button switch I was simply closing a circuit. Honestly, I'm very surprised mine is still operational after twenty seven years. I never noticed that the "Acceptable Range" for our hull is identified on my meter, can't believe I missed that and I'm anxious to get back to the boat and see this for myself. Looking forward to seeing the through hull when I haul the boat. I am hopeful we figure out who still manufactures these through hulls because they sound unique being 8" in diameter with a 2" silver coated disc. Sooner or later someone is going to need a replacement and we need to find them. Another great item for the store! I'm also hopeful your successful in posting the owners manual.
Last edited by carl on Thu Feb 09, 2017 1:15 am, edited 2 times in total.
1990 Marinette 32' Sedan Fly Bridge "IKOI"
Twin Crusader 350's (Closed Loop Cooling)
Bow to Stern Full On Restoration in Progress
Chickamauga Lake, Tennessee
A boat is always safe at shore, but that's not what its built for...

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carl
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Joined: Sun Feb 08, 2015 5:58 pm

Re: Understanding the CAPAC

Postby carl » Mon Feb 06, 2017 12:32 pm

Unbelievable, I found it online at this link, it is the exact same meter and the through hull is as you described, still available, made by Sieman's but very pricy, but there still available. Next I will reach out to Sieman's and see if they will send us an owners manual.

http://www.wardsmarine.com/downloads/on ... rosion.pdf
Last edited by carl on Thu Feb 09, 2017 1:16 am, edited 1 time in total.
1990 Marinette 32' Sedan Fly Bridge "IKOI"
Twin Crusader 350's (Closed Loop Cooling)
Bow to Stern Full On Restoration in Progress
Chickamauga Lake, Tennessee
A boat is always safe at shore, but that's not what its built for...

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Busia
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Re: Understanding the CAPAC

Postby Busia » Mon Feb 06, 2017 2:14 pm

Wow! $500 for the meter! Yes, this is just a little electrical cell " battery" you are making with the hull and sensor, with the water as the electrolyte. Go to boatzincs.com to read and learn all about this. Best prices and service when you want to buy anodes. They have a test electrode for $125 and get a $10 VOM and you have the same thing. I put a new bottom on my boat and got rid of all the holes I could. I removed the sensor and now just hang it over the side with my VOM set to mV in series with the sensor and the hull. --Ed
BUSIA
located in Ketchikan, Alaska. Gods country
32 foot Marinette express. (no fly bridge)
twin 350 Crusader (Chev 350) engines
1:1 Borg Warner velvet drive transmissions
Closed cooling (antifreeze in the engine)
Proud to be retired IBEW

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carl
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Re: Understanding the CAPAC

Postby carl » Mon Feb 06, 2017 2:43 pm

Busia,
What did you use to plug the hole in place of the Capac through hull?
1990 Marinette 32' Sedan Fly Bridge "IKOI"
Twin Crusader 350's (Closed Loop Cooling)
Bow to Stern Full On Restoration in Progress
Chickamauga Lake, Tennessee
A boat is always safe at shore, but that's not what its built for...

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Busia
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Posts: 174
Joined: Tue Jul 15, 2014 12:21 am

Re: Understanding the CAPAC

Postby Busia » Mon Feb 06, 2017 3:27 pm

Welded 3/16" new bottom on the whole hull. Holes can be patched too if you find a good welder.
BUSIA
located in Ketchikan, Alaska. Gods country
32 foot Marinette express. (no fly bridge)
twin 350 Crusader (Chev 350) engines
1:1 Borg Warner velvet drive transmissions
Closed cooling (antifreeze in the engine)
Proud to be retired IBEW

jralbert
Site Admin
Posts: 394
Joined: Fri Jul 11, 2014 9:15 pm

Re: Understanding the CAPAC

Postby jralbert » Mon Feb 06, 2017 11:50 pm

check the attachments - lots of pages but here is the Capac Manual. The site wouldn't let me upload PDF's so here is a jpg version. Sorry if the print is light.
Attachments
Capac Monitor Manual (2).jpg
Capac Monitor Manual (3).jpg
Capac Monitor Manual (4).jpg
Capac Monitor Manual (5).jpg
Capac Monitor Manual (6).jpg
Capac Monitor Manual (7).jpg
Capac Monitor Manual (8).jpg
Capac Monitor Manual (9).jpg
Capac Monitor Manual (10).jpg
Capac Monitor Manual (11).jpg
Capac Monitor Manual (12).jpg
Capac Monitor Manual (13).jpg
Capac Monitor Manual (14).jpg
Capac Monitor Manual (15).jpg
Capac Monitor Manual (16).jpg
Capac Monitor Manual (17).jpg
Capac Monitor Manual (18).jpg
Capac Monitor Manual (19).jpg
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

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carl
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Re: Understanding the CAPAC

Postby carl » Tue Feb 07, 2017 6:04 am

Joel,
Posting the owners manual page by page was great, priceless to me as I read every word and studied every diagram. Like others have said its a very simple system and I have a full understanding of it now. This simple system is a very important one that I will be looking at regularly from now on, I will start a small logbook dedicated to the CAPAC where every time I check it I will log the date, time and reading, then I will be able to track and trend, once the boat is hauled and I change out all of the anodes it will be interesting to see if my meter readout changes and if so by how much. I feel good about mine still working after 27 years. My meter is pristine, looks like it just came out of the box, the reference electrode I will have to inspect at my first haul out. Great knowing the replacement electrode kit is still available online should I need one. I read where someone found that their plastic disc was missing at haul out. Thank you for all of your help everyone.
Last edited by carl on Thu Feb 09, 2017 1:17 am, edited 1 time in total.
1990 Marinette 32' Sedan Fly Bridge "IKOI"
Twin Crusader 350's (Closed Loop Cooling)
Bow to Stern Full On Restoration in Progress
Chickamauga Lake, Tennessee
A boat is always safe at shore, but that's not what its built for...


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