Well, what an experience. Took the fam out around the islands for a two week cruise during the July 4 celebration. Noticed a more than normal amount of sea water in the main bilge after each shut down. Also, quite a bit of seawater in the bilge beneath the engine that was never there before. Wha sup? Checked all the obvious hose connections, stuffing box, packing glands, etc., etc.., etc. No noticeable water leaks.
After they left for home in Texas, I went back to the boat for a more serious examination. My first thought was the Genset, so ran it for several minutes checking all the points of water connections with a bright flashlight. Nope, zip, nada. Shut her down and fired up the main engine and went through the entire compartment with a bright flashlight. Still nothing. Then I happened to glance above the Genset platform and just by chance noticed water spitting out of the connection where the vacuum breaker connects to the mixing elbow located high up on the starboard bulkhead. Its purpose is to prevent sea water from siphoning back into the main engine after shutdown, since much of it is below the waterline. What I also learned in the process was that the sea water pump brings water in and pushes it through the system; heat exchanger, mixing elbow, exhaust. The vacuum breaker works like a joker valve. It closes when water is pushed through the system and opens to allow air to break the vacuum. Boy was I confused until Jeff Gay cleared things up for me.
To do all this examination I had to remove the front hatch to the engine compartment and even with one long arm I could just reach the vacuum breaker. When I touched it, it just fell off into my hand. The breaker is plastic and the vented loop is one inch SS tubing. The breaker itself was in good condition, but the adapter used to attach the two failed due to age fatigue. I tried an easy out to remove the old piece from the loop, but nope. What if I were to just use some adhesive or epoxy to stick it back on? Easy enough, but just temporary. This fix needs a permanent solution.
Then I began the hunt for a replacement. Rather than name names, some never called me back, even after follow-up calls. At the time it seems a complete new vented loop was in order, one made of Marelon, perhaps, at a cost of between $40 - $70 depending on suppler. But all I really needed was this two step down (5/8" to 3/8") plastic adapter.
Access to the vented loop was another problem. No way from the front, unless I moved the Genset, a major project. Instead, removing the 50 pound Xantrex charger/inverter seems a better solution with rear access. But first the adapter. Jeff Gay at Harbor Marine in Everett has always been very helpful, especially back when I had a Genset water pump impeller problem, and very knowledgeable when it comes to marine systems. He offered over the phone a new Jabsco vented loop, but what about just the adapter? Bring it in and let's take a look see.
Walked back to Jeff's office and presented to him my broken adapter and working vacuum breaker and he said, "follow-me". He went to this rack of bins on the floor looking for this two step adapter and lo and behold he had one in brass for $8. Now it was time to get serious. He gave me tips on how to remove the old broken piece out of the vented loop by using a vice to hold the loop and a small chisel to chip out the old material.
The biggest chore was to remove the charger/inverter. I installed it myself several years ago, so was a bit familiar with what to do. Got it out, which made for much better rear access with two arms rather than one and removed the vented loop. The old material popped right out after chipping out parts of the old broken nipple. Jeff suggested using liquid thread sealer, which I did, when threading on the new adapter to the loop as I also did with the vacuum breaker. Put it all back together and did an engine test. No leaks, period. Then a sea trial was in order just to make sure, so off I went for a week long trial around the islands. What a great feeling. I suppose I could have hired a tech to do the job for maybe $600 to $800 or more. Rather do it myself, so I know what makes all the systems on this P42 beast work. I remember looking at the vented loop over the years, but never paid much attention to it. I always assumed, by mistake, that it was part of the sewage system. Now I know.
Thank you Jeff Gay, Harbor Marine, Everett, WA.
The pic below shows the one inch SS vented loop behind the large black hose.
The pic below shows the vacuum breaker and broken adapter that is connected to the top of the vented loop. The right side of the adapter shows brown stain where the 3/8" threaded nipple was once a part of the adapter, now stuck in the vented loop.
The pic below shows the original vacuum breaker that still works with the new brass adapter.
The pic below shows the vented loop back in place with the new adapter and vacuum breaker installed.
After they left for home in Texas, I went back to the boat for a more serious examination. My first thought was the Genset, so ran it for several minutes checking all the points of water connections with a bright flashlight. Nope, zip, nada. Shut her down and fired up the main engine and went through the entire compartment with a bright flashlight. Still nothing. Then I happened to glance above the Genset platform and just by chance noticed water spitting out of the connection where the vacuum breaker connects to the mixing elbow located high up on the starboard bulkhead. Its purpose is to prevent sea water from siphoning back into the main engine after shutdown, since much of it is below the waterline. What I also learned in the process was that the sea water pump brings water in and pushes it through the system; heat exchanger, mixing elbow, exhaust. The vacuum breaker works like a joker valve. It closes when water is pushed through the system and opens to allow air to break the vacuum. Boy was I confused until Jeff Gay cleared things up for me.
To do all this examination I had to remove the front hatch to the engine compartment and even with one long arm I could just reach the vacuum breaker. When I touched it, it just fell off into my hand. The breaker is plastic and the vented loop is one inch SS tubing. The breaker itself was in good condition, but the adapter used to attach the two failed due to age fatigue. I tried an easy out to remove the old piece from the loop, but nope. What if I were to just use some adhesive or epoxy to stick it back on? Easy enough, but just temporary. This fix needs a permanent solution.
Then I began the hunt for a replacement. Rather than name names, some never called me back, even after follow-up calls. At the time it seems a complete new vented loop was in order, one made of Marelon, perhaps, at a cost of between $40 - $70 depending on suppler. But all I really needed was this two step down (5/8" to 3/8") plastic adapter.
Access to the vented loop was another problem. No way from the front, unless I moved the Genset, a major project. Instead, removing the 50 pound Xantrex charger/inverter seems a better solution with rear access. But first the adapter. Jeff Gay at Harbor Marine in Everett has always been very helpful, especially back when I had a Genset water pump impeller problem, and very knowledgeable when it comes to marine systems. He offered over the phone a new Jabsco vented loop, but what about just the adapter? Bring it in and let's take a look see.
Walked back to Jeff's office and presented to him my broken adapter and working vacuum breaker and he said, "follow-me". He went to this rack of bins on the floor looking for this two step adapter and lo and behold he had one in brass for $8. Now it was time to get serious. He gave me tips on how to remove the old broken piece out of the vented loop by using a vice to hold the loop and a small chisel to chip out the old material.
The biggest chore was to remove the charger/inverter. I installed it myself several years ago, so was a bit familiar with what to do. Got it out, which made for much better rear access with two arms rather than one and removed the vented loop. The old material popped right out after chipping out parts of the old broken nipple. Jeff suggested using liquid thread sealer, which I did, when threading on the new adapter to the loop as I also did with the vacuum breaker. Put it all back together and did an engine test. No leaks, period. Then a sea trial was in order just to make sure, so off I went for a week long trial around the islands. What a great feeling. I suppose I could have hired a tech to do the job for maybe $600 to $800 or more. Rather do it myself, so I know what makes all the systems on this P42 beast work. I remember looking at the vented loop over the years, but never paid much attention to it. I always assumed, by mistake, that it was part of the sewage system. Now I know.
Thank you Jeff Gay, Harbor Marine, Everett, WA.
The pic below shows the one inch SS vented loop behind the large black hose.
The pic below shows the vacuum breaker and broken adapter that is connected to the top of the vented loop. The right side of the adapter shows brown stain where the 3/8" threaded nipple was once a part of the adapter, now stuck in the vented loop.
The pic below shows the original vacuum breaker that still works with the new brass adapter.
The pic below shows the vented loop back in place with the new adapter and vacuum breaker installed.
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