Reply
 
Thread Tools Search this Thread Display Modes
 
Old 10-31-2018, 02:56 PM   #1
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
Holding tank access port?

What is the minimum size access port that would be useful in a holding tank? I would think the bigger the better but I donít have much room on top. I assume it belongs on top and not on the side? Second, what type of port is best to install? Canít imagine it is one of the spin in spin off types used topsides?
__________________
Advertisement

firstbase is offline   Reply With Quote
Old 10-31-2018, 03:17 PM   #2
Guru
 
HeadMistress's Avatar


 
City: AR
Country: USA
Join Date: Jul 2009
Posts: 1,608
The so-called "standard" size is 3", but you can get 'em up to 10". You should be able to find the one you want here: 3" inspection ports etc


No sealant needed...a rubber gasket under the flange and an o-ring on the cap keeps it sealed completely.



--Peggie
__________________

__________________
© 2019 Peggie Hall
Specializing in marine sanitation since '87.
Author "The NEW Get Rid of Boat Odors"
HeadMistress is offline   Reply With Quote
Old 10-31-2018, 03:18 PM   #3
Guru
 
Comodave's Avatar
 
City: Au Gres, MI
Country: US
Vessel Name: Never Say Never
Vessel Model: President 41 DC
Join Date: Jul 2015
Posts: 3,625
I am not sure I would want one in my holding tank, I would be afraid it might leak. Maybe someone knows of one that will not leak. Let’s see what everyone’s says.

Peggie beat me to it.
Comodave is online now   Reply With Quote
Old 10-31-2018, 03:24 PM   #4
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 12,170
Greetings,
Mr. fb. The dip tube in our holding tank (40 gal. aprox) sprung a leak last year necessitating a replacement. The tank is triangular and is in the hull right in the bow. Tank is FRP. The access hatch is aprox. 10"X10" (on top) and was plenty big enough for me to maneuver tools and replacement parts inside. The hatch is a FRP plate 3/8" thick held on via nuts and bolts, the bolts being held in place integral with the top of the tank. A well greased neoprene gasket effects the seal.
__________________
RTF
RT Firefly is online now   Reply With Quote
Old 10-31-2018, 05:41 PM   #5
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
Thanks. Here is a picture taken during poopapalooza when the vent hose blew off and $^i# happened. As you can see, little room on the top that is exposed. Maybe on the rear of the left side. Not much room though. The remainder of the tank is under the generator. I could use the plate that is already there but would prefer something simpler than removing 8 bolts. Looks like the base on the 3" port is 5". I don't think that will work. Guess I'm stuck with the 8 bolt solution but its a pain and will lead to less frequent cleanings.
Attached Thumbnails
Click image for larger version

Name:	IMG_1859b.jpg
Views:	25
Size:	133.0 KB
ID:	82420  
__________________
Hal
BLACK EYED SUSAN
Grand Banks 42 Classic
firstbase is offline   Reply With Quote
Old 10-31-2018, 05:52 PM   #6
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 12,170
Greetings,
Mr. fb. I suspect you're overthinking the necessity for "frequent" tank cleanings. A healthy holding tank should not need to be cleaned other than pumping and flushing with fresh water. A task that can easily be accomplished without any disassembly. MY $.02.
__________________
RTF
RT Firefly is online now   Reply With Quote
Old 10-31-2018, 06:01 PM   #7
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
RTF, as you know, your $.02 is worth $.04 to me. Will just deal with the bolts. You are right, just overthinking.

There is an overstinking joke in here somewhere I'm just too tired to go find it.
__________________
Hal
BLACK EYED SUSAN
Grand Banks 42 Classic
firstbase is offline   Reply With Quote
Old 10-31-2018, 06:12 PM   #8
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 12,170
__________________
RTF
RT Firefly is online now   Reply With Quote
Old 10-31-2018, 06:14 PM   #9
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
And...there you go!
__________________
Hal
BLACK EYED SUSAN
Grand Banks 42 Classic
firstbase is offline   Reply With Quote
Old 10-31-2018, 06:21 PM   #10
Guru
 
Giggitoni's Avatar
 
City: Vallejo, California
Country: United States
Vessel Name: Mahalo Moi
Vessel Model: 1986 Grand Banks 42 Classic
Join Date: Jun 2008
Posts: 1,715
I’m currently rebuilding my original setup. The eight bolts screw into a tapped metal flange INSIDE the holding tank. The hex-heads of the bolts are 10 mm. The threads are 1/4-20. I tried to think of a way to simplify the removal also. However, RT and Peggy are correct. If we take care of our holding tanks with regular flushing when we pump out, we shouldn’t have a need to open the top all that often. Keep it aerobic!

When I complete my rebuild, I’ll start another thread to “tell all” what I did.
__________________
Ray
"Mahalo Moi"
1986 GB-42 Classic
ΜΟΛΩΝ ΛΑβΕ
Giggitoni is online now   Reply With Quote
Old 10-31-2018, 06:28 PM   #11
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
Thanks Ray. Yours is a 1986 and mine an '87. Is yours a fiberglass holding tank? The flange is embedded in the glass, correct?
__________________
Hal
BLACK EYED SUSAN
Grand Banks 42 Classic
firstbase is offline   Reply With Quote
Old 10-31-2018, 06:54 PM   #12
Guru
 
Giggitoni's Avatar
 
City: Vallejo, California
Country: United States
Vessel Name: Mahalo Moi
Vessel Model: 1986 Grand Banks 42 Classic
Join Date: Jun 2008
Posts: 1,715
Yes, fiberglass. And, yes, the flange is embedded in the glass. The distance between the bolt hole centers is 2 1/8”. I’m using the space on the left in your photo (I don’t have a tank level sensor) to install the discharge hose from the aft head and the vent hose. The discharge and vent hoses will utilize uniseals. The suction hose with dip tube will use PVC bulkhead fittings.

The original GB fittings were copper tubes brazed onto a bronze plate (like yours). My copper tubes were dissolved away and the bronze plate was chemically changed to a brittle pos! Obviously GB didn’t read Peggy’s book! I’m using a 1/4” fiberglass sheet to replace the bronze plate.

Again, I will detail my rebuild in about one week, after I install and work out the details.

Edit: In the mean time take a look at the following:

http://www.trawlerforum.com/forums/a...9&d=1540243001
__________________
Ray
"Mahalo Moi"
1986 GB-42 Classic
ΜΟΛΩΝ ΛΑβΕ
Giggitoni is online now   Reply With Quote
Old 10-31-2018, 08:52 PM   #13
Guru
 
Steve's Avatar
 
City: Thibodaux, Louisiana
Country: USA
Vessel Name: Gumbo
Vessel Model: 2003 Monk 36
Join Date: Oct 2007
Posts: 3,833
Mine is a 45 Gal poly tank, it has a 4 maybe 6" opening flange and screw in cover. It is very handy, every once in a while we will stop at a marina with in slip pump out. I'll pump out the tank, open the inspection cover then bring a garden hose with a nozzle and give it a good pressure wash out through the inspection hole, then pump out again for a clean tank. That can all be done at the pump out station too if they are not busy, and a generous tip. (that hose is not the same one I use to fill the water tank)
Attached Thumbnails
Click image for larger version

Name:	head and holding tank 018.jpg
Views:	17
Size:	145.3 KB
ID:	82422  
__________________
Steve W.
http://mvgumbo.blogspot.com/
Steve is offline   Reply With Quote
Old 10-31-2018, 09:58 PM   #14
Guru
 
firstbase's Avatar
 
City: Jupiter, Florida
Country: United States
Vessel Name: Black Eyed Susan
Vessel Model: Grand Banks 42' Classic
Join Date: Nov 2016
Posts: 1,195
Thanks. My cover plate is in good shape and the discharge tube had already been replaced by the PO. I had to replace the vent connection as it was rotted and blocked. Will rebuild and replace the whole connection plate as I am not 100% happy with the vent connection. Would like to add a second vent line for better cross ventilation as well as a second holding tank for the forward head. Would like to do all of this at once, to include a good cleaning of the tank, as getting to it and opening the plate isn't much of a fun Saturday. Hence my questions about adding an access port.
__________________

__________________
Hal
BLACK EYED SUSAN
Grand Banks 42 Classic
firstbase is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 04:31 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012