Oil Leak at oil pressure sensor

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rwbower
Posts: 11
Joined: Sat May 27, 2006 5:58 pm
Location: Anacortes, Washington(Skyline)

Oil Leak at oil pressure sensor

Post by rwbower »

I have developed an oil leak that appears to be at or near the oil pressure sensor. I replaced the original sensor about 2 years ago when one of the electrical tabs broke off of the original sensor I replaced the original sensor by screwing the new sensor into the engine metal to metal without any sealer applied to the threads. It was very difficult to remove and replace the new sensor but we found a tool that allowed a blind removal and attachment of the sensor. All appeared well until recently when we found oil leaking into the pan beneath the engine and into the bilge. The leakage appears to have increased significantly on a recent trip. During this trip I removed the oil from the bilge and beneath the engine with a cup and adsorbent sheets and checked the tightness of the oil pressure sensor. I then put adsorbent sheets beneath the engine where the oil collected and right beneath the oil pressure sensor. I refilled the oil to the appropriate level and started the engine. Oil appeared to collect on the adsorbent sheet below the oil pressure sensor and eventually into pan beneath the engine. We returned home with the boat from the San Juan's, sailing as much a possible, but had to add about 2 quarts of oil to keep it properly filed during the ~2 hours of engine running on this return trip. Thus, the leak has become substantial and the only leak appears to be from the area of the oil pressure sensor. Is it possible that this replaced oil pressure sensor is leaking because the metal to metal threads do not provide a leak proof seal. If so, what type a sealant might be appropriate to stop the oil leakage?
I am interested in purchasing a dingy-davit system for my cat 350. Currently a Walker Bay Genisius and a St Croix 400 Rotating system look like it might be a good choice. Appreciate comments or suggestions
KenKrawford
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Re: Oil Leak at oil pressure sensor

Post by KenKrawford »

Did you check to see if your replacement sensor was loose? I can't imagine loosing that much oil unless the sensor was loose or (perish the thought) it was cross threaded.
Ken Krawford
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C350 # 351
Lake Lanier, GA
rwbower
Posts: 11
Joined: Sat May 27, 2006 5:58 pm
Location: Anacortes, Washington(Skyline)

Re: Oil Leak at oil pressure sensor

Post by rwbower »

When the new sensor was first inserted it felt loose and we tightened it. It now feels very tight. I agree with you that it might be cross treated, which would be terrible. We will have to check to see. A few more questions appear unanswered.
1. Why would the leak only appear 2 years later?
2. Why would it then go from a very slight leak to what now appears to be a heavy leak?
3. Upon inspection of the original sensor, which luckily we still have, the outer threads (toward the body of the sensor appear to have a coating of what might be silver paint of a sealant. Again I wonder if a sealant is required on the threads to prevent leakage of oil under pressure? I agree it seams like a great deal of oil to escape in that short of time, but it seems like a great deal of oil for a cross threat also. Then the delay time before the leakage began also seems puzzling. Also, I can't imagine the sensor diaphragm ruptured because the alarm light and sound still functions properly.
I am interested in purchasing a dingy-davit system for my cat 350. Currently a Walker Bay Genisius and a St Croix 400 Rotating system look like it might be a good choice. Appreciate comments or suggestions
rwbower
Posts: 11
Joined: Sat May 27, 2006 5:58 pm
Location: Anacortes, Washington(Skyline)

Re: Oil Leak at oil pressure sensor

Post by rwbower »

update;
1. original oil sensor failed
2. bought and installed a new sensor which appeared to fix the problem.
3. Then a year later new sensor began leaking.
4. Bought another new sensor, established first new sensor had a ruptured diaphragm.
5. Installed the 2nd new sensor and all now seams well. I will update if problem reappears.
I am interested in purchasing a dingy-davit system for my cat 350. Currently a Walker Bay Genisius and a St Croix 400 Rotating system look like it might be a good choice. Appreciate comments or suggestions
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wcconway
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Joined: Sun Nov 11, 2007 1:39 pm
Location: Pensacola, Florida

Re: Oil Leak at oil pressure sensor

Post by wcconway »

We really like our Kato davits with a stabilizer bar. The support bars are great handholds for getting in and out of the dinghy and the swim ladder.
Wally & Coco Conway
, #467
Pensacola, Florida
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