Fuel Filters

[Mariner]

Either way, the first filter should be at least as fine as the on-engine filter.

[jleonard]

I read Tony's article some time ago and fashioned my current system based on that article's principles.
When we bought the boat last year (an older 40 Albin single diesel) I could only get about 6 running hours out of a Racor 500 element. The PO was using 2 micron filters.
I added a Racor 900 at 30 micron as the primary, then went with 10 micron in the secondaries (a dual unit), both with vacuum gages.
The engine's last chance filters are 7 micron.
Last season I got 80 hours out of a set of filters...still had zero vacuum, but I changed filters this spring.....new season..new filters and all that.
So far this season still at zero vacuum (maybe 50 hours so far).
The "multi-stage" principle works well. I highly recommend it.

[N4QC]

For Racor 500FG users built before 1998, be noticed that the new filters for the older 500FG units require a retrofit spacer, otherwise you will see your engine filter clog real fast...

The spacer is available free from Racor tech support and is packaged with replacement filters shipped in the last nine months or so... The spacer is not expected to be shipped with the new filters after a year or so.

A vacuum gauge is a good instrument to have. I found the gauge and the Racor filter notice on the following site:

http://www.designatedengineer.com/

Good luck,

[Merry Kate]

Jay -

I've used the on-filter Racor vacuum guage for years on my single 900MA and works well, but don't completely trust them when they read 'zero':

Was bringing a year-old Searay 56 up from FLA to VA which had 1050 MANs, each with 2 giant Racor 1000MAs & switchable plumbing with vacuum guages. Got all the way to Hampton Roads and in 4-5 ft 'square' seas, started loosing RPM and electronic guages showed engine loading way up. OK, no-brainer - check filters, right? So they send me down to the engine room with a bucket to puke in. Both engines showed '0' on filter vacuum guages. Switched to each primary filter in sequence, still '0' vacuum, still losing RPMs. WTF? So limp into Reedville at idle rather than dealing with it in those conditions. After much perplexing, changed all primary filters, which were completely black & crudded, and - bam - motors making 1000 HP again.

Never found out what the problem with the guages was: installed wrong, something clogging them, or what. But it led us down a stray path checking all sorts of other things. Now I don't completely trust them unless I know the installation. You know yours work, but keep an eye on them & make sure they eventually register some restriction to be sure all's right.