Tom Metzger
Sustaining Partner
There have been lots of threads about filters, and lately one starting off about fuel pumps, that referred to the filter ratings of the Universal diesel fuel filter. Most of the info reported is hearsay and peaked my curiosity.
Because I found it difficult to find ratings I believed, except for the 10 micron Wix 33390 (NAPA 3390) I started emailing Universal/Westerbeke “master” distributors asking if 10 microns was the recommend filtering level and if they recommend 30 microns for the Racor primary filter.
My distributor in the Northeast, Hansen, didn’t reply to my email. Some days later I asked a couple of others, one in Florida and one in California and got responses that I didn’t trust.
Today I emailed Westerbeke and got an interesting answer.
“Hello Tom,
10 microns for the on engine spin on filter is fine. Do not go any smaller in micron rating. Our #298854 spin on is rated at 25 micron. Stay with 10 micron in the Racor as well. You want the Racor to be doing the majority of filtering.
Kind Regards,
Westerbeke Corp.”
This does not support the conventional wisdom that the engine mounted filter should finer than the primary filter. It does support my feeling that the engine fuel filter doesn’t need to be changed very frequently.
Because I found it difficult to find ratings I believed, except for the 10 micron Wix 33390 (NAPA 3390) I started emailing Universal/Westerbeke “master” distributors asking if 10 microns was the recommend filtering level and if they recommend 30 microns for the Racor primary filter.
My distributor in the Northeast, Hansen, didn’t reply to my email. Some days later I asked a couple of others, one in Florida and one in California and got responses that I didn’t trust.
Today I emailed Westerbeke and got an interesting answer.
“Hello Tom,
10 microns for the on engine spin on filter is fine. Do not go any smaller in micron rating. Our #298854 spin on is rated at 25 micron. Stay with 10 micron in the Racor as well. You want the Racor to be doing the majority of filtering.
Kind Regards,
Westerbeke Corp.”
This does not support the conventional wisdom that the engine mounted filter should finer than the primary filter. It does support my feeling that the engine fuel filter doesn’t need to be changed very frequently.
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