Grand Banks Discussion Forum

[Mike Negley]

Two of the most common engine related replacement parts are Racor fuel filters and zinc anodes for the cooling system. The best on-line sources I have found for these are www.marinefilters.com for filters and seal service kits and [url]www.boatzincs.com [/url]for the zinc anodes. Both offer excellent service and usually the best prices anyplace. MarineFilters.Com no longer requires a minimum order of 12 (case lot) which makes it even better. The seal service kits include the gaskets, washers and check valve necessary to restore the filter assembly to original factory condition after a thorough cleaning. This is not a difficult job and was covered in an earlier article (http://www.gbbeacon.com/phpBB2/viewtopic.php?t=9543).
I also wrote an article on replacing zinc anodes at (http://www.gbbeacon.com/phpBB2/viewtopic.php?t=9496) which explained how to re-use the old brass plugs so you only have to buy the threaded zinc pencil. The savings in comparison to what local chandler's charge is substantial.
At the risk of starting another controversy which is always fun and exciting I continue to recommend using 30 micron primary fuel filters for pre-common rail diesel engines. Actually the Racor Turbine series filters are more valuable to separate out water than remove particles, but they do both very well. Virtually every marine diesel has an on-engine secondary filter ranging from about 3 to 8 micron filtration. Basically this is the manufacturer’s statement as to what minimum level of fuel cleanliness they require.
The primary and secondary filters are all based upon “edge particle” filtration meaning the particles are caught and trapped on the outside edge of the filter element. Interestingly these trapped particles become part of the filter in a process called “caking”. In other words, the particles increase the filter’s efficiency up to the point it gets clogged and must be replaced altho it is possible to clean a filter in place which I will come to in a moment.
In the case of Racor they offer three grades of filtration; 30, 10 and 2 micron. If you use a 10 or 2 micron filter as primary, it will remove so much of the particle count available to the secondary filter that little or no coating will occur. Therefore two unwanted things occur; the primary will clog faster and the secondary will be less efficient than expected by the engine manufacturer.
I am well aware of the argument against this concept in that it is easier to change the primary filter which is valid. However, I am not aware of any engine manufacturer that recommends the primary filter be 2 micron and while most will accept 10 micron, most still prefer 30 micron especially on the large engines because they want particles to get thru the primary filter and cake the secondary.
Now about cleaning a Racor filter in place. You can take a small Par Junior hand pump and connect it to the drain port on the bottom of the sight glass and then pump like mad to create a vacuum inside the filter. You will see the particles start to come off the edge of the filter as they are pulled downward into the pump. However, for less than $8 you can replace the filter if you buy from MarineFilters.com.

[cherr]

Is there a recommended service interval for doing the Racor "overhaul"?
_________________
Chuck Herr
GB-46/17
"Mairead"

[Mike Negley]

I would think in terms of every five years for a typical recreational vessel running 200 hours per year, so we might say every 1,000 hours or five years whichever comes first. However, the sight glass often becomes clouded before this so perhaps every 500 hours or 2.5 years for cleaning the sight glass only and then a rebuild the next time. The only way to get the sediment out of the bottom of the sight glass is to empty the fuel and remove it which is not a bad job especially if you are changing filter elements anyway. The worst part is getting diesel all over your hands and clothes so wear solvent resistant gloves and consider old throwaway clothes.