Secondary Fuel Filter Not Needed

[Jeff652]

I was perusing Catalina Direct web site and I was surprised to see that the secondary fuel filter (Universal filter 48076) is not required. This filter is often sold with the fuel lift pump Here is what they say:

"This pump was used on engines listed below (and the boats that we are aware used these engines... There could be other combinations as well):

• M-25XPB (Catalina 28 MkII, Catalina 30 MkIII, Catalina 310)

• M-35B (Catalina 34 MkII, Catalina 350, Catalina 36 MkII)
  Notes:
  1) Pump comes with an 80 micron filter which is not needed as long as your boat has the fuel filter / water separator installed, standard equipment on Catalinas, between the fuel tank and this replacement pump."

Not a real big deal but it will save me $37 per year.

Jeff
s/v Still Crazy

 

[LeslieTroyer]

Are you confusing the filter inside the fuel pump that should be changed once every 6 years (or so) with the on engine spin-on filter that should be changed every 1-2 yrs??

You can get each of these filters for 1/4 the Universal price on amazon or Napa. Lots of cross reference tables out there

 

[Don S/V ILLusion]

I often wondered how I and the diesel car I put 160,000 miles on over 9 years survived with just a single spin-on cartridge filter. To read all the stuff here and elsewhere regarding the necessity for marine diesel fuel multiple filter stages, it is impossible...

 

[Jeff652]

I don't think I am confusing the two. I am referring to the 80 micron secondary filter that inserts on the lower aft area of the engine (see picture with arrow), not the tertiary spin-on filter that screws on the upper forward part of the engine just before the high pressure fuel pump. This is the only 80 micron filter that I know of on the boat. And the image of the filter that comes with the lift pump looks identical to the filter on my boat (see the two photos below). ???
Jeff

 

[JimInPB]

On systems that I set up, I often have a small downstream semi-permanent filter after my main filter. The downstream filter gets a slightly larger mesh size compared to the main filter, so that it will not tend to clog up over time. It is just there to catch the stray piece of crud that accidentally enters the system when the main filter gets changed.

...But that is just me choosing to wear suspenders & a belt at the same time. A lot of guys just run one filter. I tend to be a little fussy about my fuel quality.

 

[LeslieTroyer]

@Jeff652 typically the spin on is called the secondary (even tho it is the 3 filter in the line). This one is only there to protect the fuel pump. The fuel pump filter can be changed every 6yrs or once a decade —- unless someone moved it upstream of the primary then all bets are off.

Micron ratings on fuel filters can be deceiving. A 30Micron Racor will NOT stop all particles bigger than 30Microns. It only stops about 98% of them so some particles big enough to damage or stop the lift pump can get by. This is the reason for that filter. (Similar percentages for 2 & 10 Micron filters).

I use wix 33390 filters for the on engine spin-on. You can also get these intake screw on filters substantially cheaper at NAPA.

 

[Franklin]

My primary gets changed a lot, but my secondary about once every 5 years. My primary had always been a 10 mic and secondary a 10 as well, but just recently I changed the primary to a 2 mic. Was curious if the suction pump would get the fuel through the 2 but so far so good after a 18 hours of motoring.

 

[Maine Sail]

I don't think I am confusing the two. I am referring to the 80 micron secondary filter that inserts on the lower aft area of the engine (see picture with arrow), not the tertiary spin-on filter that screws on the upper forward part of the engine just before the high pressure fuel pump. This is the only 80 micron filter that I know of on the boat. And the image of the filter that comes with the lift pump looks identical to the filter on my boat (see the two photos below). ???
Jeff

Jeff,

That filter is simply a fuel pump guard screen. The actual Facet spec is 74µM & I don't know why Westerbeke rounds it up to 80µM.. It is a required guard screen for Facet to honor a warranty on those pumps and is why Westerbeke installs them. Also severs to catch any debris induced during filter changes. They way they buy their cube-pumps from facet, it actually comes in the kit..

Your primary filter is the one directly after the tank and the secondary fuel filter is the engine spin-on. You should not need to replace your fuel pump guard filter often, if ever.

Not a real big deal but it will save me $37 per year

The prices Catalina Direct/Westerbeke is selling these guard filters for is rather steep. I do wish I could make that kind of margin but I could not do it with a straight face nor without a guilty conscience.

 

[Jeff652]

Jeff,
That filter is simply a fuel pump guard screen. The actual Facet spec is 74µM & I don't know why Westerbeke rounds it up to 80µM.. It is a required guard screen for Facet to honor a warranty on those pumps and is why Westerbeke installs them.

Yea, that makes a lot of sense. Thanks for the info. I've been changing all three filters every year even though I put on only about 50 hours a season - dock to bay, bay to dock. I've always wondered if I have to change the primary Racor R15P and my secondary spin-on filter yearly since I use the engine so little. It's not so much the money as avoiding a pain in the neck job.
Thanks for the info
Jeff

 

[LeslieTroyer]

Go to a hydrolic store and get a vacuum gauge about $20 with drag needle. Racor has charts on when their filters need changing based an vacuum. Change secondary every other primary change. Check the gauge with ~ same fuel level or see how it changes as that first tank of fuel goes thru - you’ll have more vacuum on empty tank


Les

 

[Tom J]

I installed the Racor vacuum gauge kit. As the primary filter gets clogged, the vacuum level increases, and when the needle gets into the yellow zone, it is time to change the filter. It is best to check the vacuum level at cruise rpm's.