Posted by CaptGoodSail@… (CaptGoodSail@…)
You missed my point… adding a series of filters in line creates additional negative pressure (“vacuum” in the vernacular) for the fuel pump to overcome (and small Yanmars have notoriously small pumps I might add). Essentially by installing a bunch of filters in series you are actually simulating a clogged filter element as far as the fuel pump is concerned.
That’s why your filter elements appear clean when you need replace them… they probably are still quite useable… but three filters @ 75% capacity would probably stop your engine whereas two @ only 25% capacity will probably still run fine because of the fluid dynamics involved in suctioning fuel through the multiple filters. Do you really think the 30mic Fram filter is saving you from replacing the 2 mic Racor filter?
“Illogical Capt’n”, says Spock.
BTW, The paper element mounted on the engine is really meant primarily to block water from entering the high pressure pump. Once the paper element is wet it will not pass water or fuel either. That’s how its designed. So if you have had a water problem replace the paper element immediately. Your 2 micron Racor does the serious fuel cleaning chores. Also Racor elements of different filtering abilities – 2 micron and 10 micron for the popular small diesel filters. Most older engines will be happy with the 10 micron.
Posted by Paul McFadden (pwhitmac@…>)
And that’s why I install a separate boost pump as close to the fuel tank as possible, up stream of everything! PWMCaptGoodSail@… wrote: You missed my point… adding a series of filters in line creates additional negative pressure (“vacuum” in the vernacular) for the fuel pump to overcome (and small Yanmars have notoriously small pumps I might add). Essentially by installing a bunch of filters in series you are actually simulating a clogged filter element
as far as the fuel pump is concerned. That’s why your filter elements appear clean when you need replace them… they probably are still quite useable… but three filters @ 75% capacity would probably stop your engine whereas two @ only 25% capacity will probably still run fine because of the fluid dynamics involved in suctioning fuel through the multiple filters. Do you really think the 30mic Fram filter is saving you from replacing the 2 mic Racor filter? “Illogical Capt’n”, says Spock. BTW, The paper element mounted on the engine is really meant primarily to block water from entering the high pressure pump. Once the paper element is wet it will not pass water or fuel either. That’s how its designed. So if you have had a water problem replace the paper element immediately. Your 2
micron Racor does the serious fuel cleaning chores. Also Racor elements of different filtering abilities – 2 micron and 10 micron for the popular small diesel filters. Most older engines will be happy with the 10 micron. __________________________________________________Do You Yahoo!?Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com