Mercruiser water separating gas filter cut open

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Comparison between a virgin Quicksilver water separating gas filter , and a used Sierra equivalent, in service for 2 years. The Mercruiser / Quicksilver is part 35-866340K01 and the Sierra is a popular line of marine replacement parts. The Sierra was in service for about 100 hours, or about 1200-1500 gallons of gas. The reason I post this here is because they are almost identical to oil filters. Some observations - Sierra does not seem to have any coating on the inside, while the Merc has a claimed epoxy coating. Very important considering that water builds up in the filter. - Merc internal coating had air bubbles under the paint, and the end-plate was not coated on the inside. So good idea, poor execution on the internal coating. - Sierra external coating was not as good as Merc, and had noticeable rust spots. - Sierra not apparently coated on the inside, but I did not detect any internal rust. There was a tiny bit of water present when I drained the filter into a jar. - Sierra has more filter area, Merc has more water holding capacity. - Sierra had an assembly defect- the black nitrile gasket was offset and probably did not seal 100%, which might let dirty fuel bypass the filter. - Sierra made in Taiwan, Merc in US. - Merc / QS always on left, Sierra on right if 2 pics are side by side. Honestly I was disappointed by both of them, but I would give the Merc a 6 out of 10, and the Sierra a 4 out of 10. I might consider a Racor for such an important part.
 
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[Linked Image] [Linked Image] [Linked Image] The brown smudge is sealer from the filter smeared around. The paint bubbles, which were all on the bottom, numerous and massive- the size of a US 5 cent piece , do not show up well.
 
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Fort Lauderdale, FL
Once you go Racor, you don't go back. The spin on cans are adequate for a gasoline fuel engine, but if you want industrial level filtering and separation, you can't beat a Racor or equivalent. If you get one with a solid metal bowl for USCG compliance, get the water-in-fuel sensor. If you decide to do a low-micron element (2-micron) get a vacuum gauge for the exit port. Both are cheap and easy to set up. You can change your filter and drain water by performance rather than blind assumption.
 
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Upstate NY
Most people change them once a year regardless. Both should do the job. Many Mercruiser carb engines have an additional filter at the carb.
 
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Originally Posted by DoubleWasp
Once you go Racor, you don't go back. The spin on cans are adequate for a gasoline fuel engine, but if you want industrial level filtering and separation, you can't beat a Racor or equivalent. If you get one with a solid metal bowl for USCG compliance, get the water-in-fuel sensor. If you decide to do a low-micron element (2-micron) get a vacuum gauge for the exit port. Both are cheap and easy to set up. You can change your filter and drain water by performance rather than blind assumption.
Racor makes a direct replacement for this filter, with a metal bowl. I had one on my previous boat and was very happy, so I may look into one for my current boat. Good tip on the sensor- I did not realize they had that option.
 
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6,773
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Fort Lauderdale, FL
It's a good way to know when to drain. Very good tool to have. Like most WIF sensors, it's just two contacts that bridge when immersed in water. Just hook it to the ground of a light on the dash, and you're good to go. Honestly, far from a requirement on a small tank that is used frequently enough and kept filled, but it shuts out any pondering of water contamination or when to drain the filter.
 
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I don't have a pro filter cutter but I drain my fuel water separator into a clear vessel. I never see any sign of water ???
 
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