Beneteau First 38 !! High pressure fresh water leak

[windsmaker]

I have a beneteau first 38 (1984) and have a leak in the fresh water pressure line which is leaking about gal /hour into the bilge.
I can't find the source of the leak. The fresh water pump comes on about ever 1 minute to pressure up. It is in one of the water lines leading forward from the aft and is NOT at the hot water heater or the very aft compartments.
The leak is coming from somewhere between the engine compartment and the main cabin under the stairs, if you are familiar with the b38. This in under the fiberglass floor liner which I can't see or get to.

Is there a method to locate the leak?
Is there a schematic of the fresh water plumping / tubing for the B38 that anyone can release?
I was thinking of plugging the hot water line at the hot water heater and determining if the leak is in the cold or hot line. Any thoughts?
I have been working on it for 2 days and I'm complexed as to how to find the leaking fitting.

thanks. Bob

 

[windsmaker]

Found the water leak!! .
The hot water pressure relief value was leaking and the hose was leading to under floor board where there was no fresh water pressure water lines.
The warming of the hot water heater from the engine heat resulted in the relief value leaking badly. So I only observed the leak when the hot water heater was hot. This mainly was when the engine was heating the water after running for over 30 minutes.
This is very tricky to track done as all the high pressure fitting were fine and I could fine the leak when the water heater was cold. I traced the entire system through the boat and pulled lines. A lot of work..
I replaced the pressure releif value with a 150psi / 210 degree and works fine .
However, I am concerned the the Raritian hot water heater pressure releif that was on was 75 psi / 210 degree. The small pressure pump used in the pressure water system can't get above 45 psi so I don't think it is a problem using the 150 psi.
Any thoughts? Also, the high temperature (210) would releive the pressure before the boiling point and prevent the pressure getting to high . Am I thinking this correctly?