Oil filter vs Fuel filter - Mercruiser filter cut open

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I decided to cut open a popular water-separating fuel filter used on my boat, mostly out of curiosity and to see how they work, and to compare with typical oil filters. This model - Mercruiser / Quicksilver 35-802893Q01 is very common on Mercruiser engines.
The media is supposed to be different from typical oil filter media, and has the reported capability to block out water, but many owners debate how well this works. The primary method to separate out water is by gravity: there is plenty of space below the filter media so that the heavier water sinks and does not reach the filter media.
The filter is constructed almost identical to an oil filter, as you can see by the pics. The major differences you can see are: inside of the can is painted to combat rust, but not the end plate; extra space below the media; the spring is held in place with some sticky asphalt-like adhesive; the spring is very thick; the can is fairly thick- much like a good oil filter.
 
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This is an unused filter. Some other notes: there is no ADBV ,which makes sense; there is a nitrile-looking gasket similar to a ADBV that seals the filtered side from unfiltered; the filter potting compound is fairly clean, but you can see a few small smears; the inside filter element has a date code along with the can itself. I will probably cut the media later, do some water drop tests and see how the media reacts. Any idea who actually makes this filter ?
 
Wix filters list 33226 as the comparable, but also a long version, 33225

33225 is on RockAuto for $8.50, plus probably $2.99 shipping...

Quicksilver 35-0078M9962 is even longer...
 
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Originally Posted by Donald
There may be a secondary filter at the inlet to the carb. Not sure what the newer FI boat engines have in the way of fuel filters.


The older carb engines, if using a Quadrajet, would have the carb inlet filter. The EFI engines do not.
 
Originally Posted by mattwithcats
Wix filters list 33226 as the comparable, but also a long version, 33225

33225 is on RockAuto for $8.50, plus probably $2.99 shipping...

Quicksilver 35-0078M9962 is even longer...


Good info, I checked on the Wix 33226 and it seems an exact match for the Quicksilver 35-802893Q01. A longer filter might work but sometimes there is not enough clearance. Its possible that Wix is the manufacturer of the OEM filter: can anybody tell by the base plate or date code who made the filter ?
 
It looks like it was made by Champion Labs.

I have a new NAPA/WIX (in the next size longer) for my boat - but I think it was $15 and I'm not cutting it open!
 
Excellent cutting post. Don't bother with the water drop test. These separators can only effectively separate water that is immersed in gasoline.

Personally, I prefer a good Racor installed before one of these filters in line. I have watched water droplets falling off the media down into the clear bowl on a racor separator as the engine was running. Those things are no joke.

the larger the filter separator media the better as well. The larger that the media is, the less velocity and suction will be on any approaching water droplets. Greater possibility of them simply falling out and into the bottom even before coming into contact with the media.
 
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