Diesel Fule Filter Micron Choice?

[Dave100456]

Hi
I have what I presume is a 'fine' fuel filter on my VP engine block (Part Number 31261191). Anyone know what its micron rating is?

I'm replacing a 'pre filter' Racor element; any suggestions as to what the best micron rating for this, presumably coarser than the VP one?

Thanks
Dave

 

[superheat6k]

I would suggest the on engine filter is likely to be 10 micron, and I would use 30 micron on the pre-filters. However what size filter and what size engine ?

A Racor 500 on a 25 HP engine would be just fine with 10 micron, but for likely for ever blocking on a 200HP.

My engines are 255 HP and I have 30 micron 900 size pre-filters. The cyclone effect separates out any heavier muck and I find an annual element change (~70 - 100 hours) removes a partially blackening filter where the main fuel is flowing, but not yet had a blockage, but I routinely polish my fuel, especially after a re-fuel.

 

[RichardS]

Hi
I have what I presume is a 'fine' fuel filter on my VP engine block (Part Number 31261191). Anyone know what its micron rating is?

I'm replacing a 'pre filter' Racor element; any suggestions as to what the best micron rating for this, presumably coarser than the VP one?

Thanks
Dave

Don't intend to start an argument but I suspect the engine filter is likely to be 2 microns and the preferred Racor filter on an auxiliary engine would usually be 10 micron.

Richard

 

[Heckler]

e

Don't intend to start an argument but I suspect the engine filter is likely to be 2 microns and the preferred Racor filter on an auxiliary engine would usually be 10 micron.

Richard

Not arguing either but IIRC then CAV 296 is five microns
S

 

[Heckler]

I would suggest the on engine filter is likely to be 10 micron, and I would use 30 micron on the pre-filters. However what size filter and what size engine ?

A Racor 500 on a 25 HP engine would be just fine with 10 micron, but for likely for ever blocking on a 200HP.

My engines are 255 HP and I have 30 micron 900 size pre-filters. The cyclone effect separates out any heavier muck and I find an annual element change (~70 - 100 hours) removes a partially blackening filter where the main fuel is flowing, but not yet had a blockage, but I routinely polish my fuel, especially after a re-fuel.

With the greatest of respect but, the fuel should be clean, if you are getting black on the filters then it suggests that you have some bug in the tanks!
S

 

[Dave100456]

Thanks for suggestions.
The engine is D3 110hp but on a yacht so not often working frequently at high rpm. Max consumption is litres per hr hour is 18 but usually a third of that. Is there a spec for the flow rates of the various racor filters?

 

[nigelmercier]

My filters are 10 and 2. Don't be misled by the litres/hr that the engine uses, the fuel flow is many times that.

I've got a Racor 120 on my 50HP (I think) MD22P-B, it is just big enough.

 

[superheat6k]

With the greatest of respect but, the fuel should be clean, if you are getting black on the filters then it suggests that you have some bug in the tanks!
S

No doubt, but the boat is 29 years old with inaccessible 600 lt tanks for proper cleaning. I am confident there is no loose sludge anymore, but small traces of prior bug debris are inevitable (I replaced the ridiculous Harwood spinners with the Racor 900 style filters in 2013 along with Magnetic filters). I polish monthly for an hour each side as mentioned, don't find any free water, plus I keep the boat warm throughout winter, avoiding condensation in part full tanks, and I have not suffered any fuel blockage problems, but a slow gathering of dark / black patches where the fuel flows hardest I can live with, as the residue finds it way out over time.