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vented loop question
I have a Groco bronze anti-siphon vented loop on the raw water line of my exhaust cooling system on the Yanmar. (See image below)
The other day I saw that a little water was tricking out of the small hole on the top of the bronze cap. I removed the vented loop to clean it as best I could, but it now leaks even more. I can't find a replacement part in Brazil, so I'm left with 2 options if I want to use the boat over the next months (as I wait for a replacement from abroad):
1) Repair the vented loop. Does anyone know how to service these things? Any advice for me? I tried to clean the rubber diaphragm, but it doesn't look like one can take the whole thing apart to get at the guts inside to effect a proper repair.
2) Remove the bronze cap and anti-siphon diaphragm on the top of the vented loop and attach a hose to vent overboard. This is what Groco says: "Cap is threaded 1/2" NPT to accept a barb fitting if you wish to vent overboard.". Also, my Nigel Calder book mentions the same option of attaching a hose to the top of the vented loop and bringing the hose to a place well above the waterline to vent. Calder seems to say that you remove the diaphragm before attaching the hose. This option seems the best for me as it should be the most reliable way to get a siphon break without all the fussy problems of delicate diaphragms and valves. Is it as simple as it seems to be? Do I just unscrew the top, pull out the guts and screw in a bronze hose barb and run a hose to a higher location to vent? How high above the waterline does it have to be and does it have to exit the boat or can the hose terminate inside a locker?
Thanks in advance,