Recent Topics
2004 FZ6 Delo 400
by thestockie1 - 03/30/20 04:34 AM
Turn signals all blinking fast
by JHZR2 - 03/30/20 12:14 AM
New Ram... thoughts by owners?
by wallyuwl - 03/29/20 11:38 PM
It's getting too hot...
by gregk24 - 03/29/20 08:59 PM
What tool do I need?
by 2015_PSD - 03/29/20 08:51 PM
Joe Diffie has passed away
by 53' Stude - 03/29/20 08:33 PM
Heat shield rattle
by spasm3 - 03/29/20 08:16 PM
John Deere 445, was Mobil 1 0w40 a good choice?
by zstand - 03/29/20 07:48 PM
Anyone riding?
by gman2304 - 03/29/20 07:27 PM
Thermostat housing gasket leaking
by motor_oil_madman - 03/29/20 06:58 PM
Redline 75w/110 - UOA Included
by NorCalHD - 03/29/20 06:56 PM
Beet greens. This something new?
by atikovi - 03/29/20 06:24 PM
2018 Ford Edge Oil Question
by Passport1 - 03/29/20 04:52 PM
Help school an engineer
by DriveHard - 03/29/20 04:47 PM
Broken sway bar bolt
by HoosierJeeper - 03/29/20 04:00 PM
can I use it?
by avi1777 - 03/29/20 03:54 PM
Service Champ OF2222 75% OLM, unknown miles
by bullwinkle - 03/29/20 03:50 PM
Gas Buddy Question
by Wolfshead - 03/29/20 03:30 PM
Caliper piston boot
by painfx - 03/29/20 03:25 PM
Graphene the next detailing protection
by Mamala Bay - 03/29/20 02:17 PM
Newest Members
IMSA_Racing_Fan, Warrengk, thestockie1, FrostFire, Richierich56
71046 Registered Users
Who's Online Now
29 registered members (Bailes1992, bachman, bbhero, 1foxracing, avi1777, 25ring, 3 invisible), 741 guests, and 21 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics303,336
Posts5,234,212
Members71,046
Most Online4,538
Jan 20th, 2020
Donate to BITOG
Print Thread
Hop To
Mercruiser water separating gas filter cut open #5131928 06/12/19 01:32 AM
Joined: Jul 2008
Posts: 1,417
R
rubberchicken Offline OP
OP Offline
R
Joined: Jul 2008
Posts: 1,417
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.

Last edited by rubberchicken; 06/12/19 01:48 AM.
Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5131930 06/12/19 01:37 AM
Joined: Jul 2008
Posts: 1,417
R
rubberchicken Offline OP
OP Offline
R
Joined: Jul 2008
Posts: 1,417
[Linked Image]
[Linked Image]
[Linked Image]

Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5131932 06/12/19 01:46 AM
Joined: Jul 2008
Posts: 1,417
R
rubberchicken Offline OP
OP Offline
R
Joined: Jul 2008
Posts: 1,417
[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.

Last edited by rubberchicken; 06/12/19 01:55 AM.
Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5131933 06/12/19 01:47 AM
Joined: Jul 2008
Posts: 1,417
R
rubberchicken Offline OP
OP Offline
R
Joined: Jul 2008
Posts: 1,417
[Linked Image]
[Linked Image]
[Linked Image]

Merc / QS on left, Sierra on right

Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5131976 06/12/19 04:26 AM
Joined: May 2012
Posts: 6,773
DoubleWasp Offline
Offline
Joined: May 2012
Posts: 6,773
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.


07 Lincoln Navigator M1 0w-40/FU
68 Charger R/T / Supercharged 440 VR1/DBL7349
07 Ram 3500 4x4 / Cummins 6.7 /DBL7349
17 Maserati GranTurismo Cabrio
Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5132208 06/12/19 10:37 AM
Joined: Mar 2004
Posts: 24,046
D
Donald Offline
Offline
D
Joined: Mar 2004
Posts: 24,046
Most people change them once a year regardless. Both should do the job. Many Mercruiser carb engines have an additional filter at the carb.


2015 Ford F-250 w/Powerstroke
2016 Subaru Crosstrek CVT (wife's)
Re: Mercruiser water separating gas filter cut open [Re: DoubleWasp] #5132601 06/12/19 07:43 PM
Joined: Jul 2008
Posts: 1,417
R
rubberchicken Offline OP
OP Offline
R
Joined: Jul 2008
Posts: 1,417
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.

Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5134491 06/14/19 10:22 PM
Joined: May 2012
Posts: 6,773
DoubleWasp Offline
Offline
Joined: May 2012
Posts: 6,773
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.


07 Lincoln Navigator M1 0w-40/FU
68 Charger R/T / Supercharged 440 VR1/DBL7349
07 Ram 3500 4x4 / Cummins 6.7 /DBL7349
17 Maserati GranTurismo Cabrio
Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5145847 06/27/19 06:38 PM
Joined: Apr 2009
Posts: 154
gotnogunk Offline
Offline
Joined: Apr 2009
Posts: 154
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 ???


2018 Cadillac XTS 3.6
2014 Ford F150 3.7 supercrew
Re: Mercruiser water separating gas filter cut open [Re: rubberchicken] #5320889 01/12/20 05:02 PM
Joined: Sep 2009
Posts: 465
L
littlehulkster Offline
Offline
L
Joined: Sep 2009
Posts: 465
>So good idea, poor execution

That could be Mercury Marine's motto, honestly.


2015 Mazda3 I 2.0
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™