Possible Leaking Holding Tank

Biggin

.
May 31, 2010
26
Hunter Legend 37.5 Midland Bay Sailing Club
I have a 1990 37.5 Hunter. I have noticed very dark brown water in the bilge. No odour but very dark colour.
I fully realize the issue with the aluminum tankage in these boats.

What I am after is has anyone has actual experience replacing the tank as it is a VERY tight fit and I can't imagine removing the tank...

If it is the tank I am considering an all in one head with a smaller (6 gallon) tank. We are on the ocean to pumping out every few days is not an issue.

Interes
 
Nov 6, 2006
10,244
Hunter 34 Mandeville Louisiana
Check holding tank for sure, but... brown water and no odor could be rain water leaching through deck or cockpit floor coring ..
 
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Sep 25, 2008
7,724
Alden 50 Sarasota, Florida
You have a 36 year old aluminum holding tank and asking if it could be leaking? Reminiscent of an old Clint Eastwood movie quote.
 

BrianQ

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Jan 10, 2024
51
Hunter Legend 37.5 Havelock
While I have no direct experience removing the holding tank, I know it is possible as mine was replaced by the prior owner.
I do have direct experience removing and replacing the fuel tank through the access panel in the aft berth. The holding tank is a bit smaller than the fuel tank so removing it should be much the same, perhaps easier.

For removing the fuel tank, I emptied the contents and removed all the hoses, sending unit, and removed the four fasteners holding it down. With a little help through the access panel in the cockpit lazarette I was able to slide the tank out through the aft berth access panel without too much difficulty. Getting it back in was a bit more difficult than removing it for some reason. IIRC there is just under 3/4" difference in the height of the fuel tank and the opening in the aft berth.

For your holding tank I would recommend removing everything from the starboard cockpit lazarette to gain access to the top of the tank and to help turn and push the tank out through the aft berth access panel. For the new tank I would recommend getting one about an inch shorter to make the install easier. To make up the volume lost by going shorter you can add a few inches in depth, fore and aft as there is a bit of space aft of the tanks.
 

Biggin

.
May 31, 2010
26
Hunter Legend 37.5 Midland Bay Sailing Club
Thank you folks. After a lot of squeezing, prying as it turns out it is a small leak from the hose to my 'Y' valve.
BrianQ thank you. After reading your message I took some measurements and yes with some wrangling I think I could get it out through the access panel...tight tight..
 
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Likes: JamesG161