Twin fuel filters - what microns?

Robert Wilson

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I'm about to fit a new twin filters assembly (for 13hp Kubota).
I have in stock from previous purchases:-
One MannP917x which I believe to be 18 microns
Four VolvoPenta 3581078-7 10 microns
Three Fram C1191PL 4 microns

I know the first filter should be of greater micron filtering than the second (in line)

What does the panel think would be the best (better) combination?
Or something else?

TIA, as usual
 

PaulRainbow

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I'd fit the 18micron as a primary filter and the 4 micron as a secondary. That assumes no additional filtering on the engine.
 

Robert Wilson

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You could go 10 to 4 if you wanted, with a small engine. If there was any crap in the fuel the 10 obviously blocks up a little quicker, but still an acceptable combination.

That's good, thanks.
At least it means that is one less £outlay for the next three seasons! :encouragement:
(Unless there is a ingestion of crap!!)
 

pvb

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Yes, I bought it from ASAP. Their part no. 302009
edit: two filter housings fitted side by side with integral connecting pipe. Very neat.

OK, I used one of those on a DIY fuel polishing device. As I recall, the 2 filters are plumbed in parallel, not in series, so fitting filters of different micron sizes won't achieve what you were hoping for.
 
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Robert Wilson

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Ah! :(
If I have that set-up I'll be very annoyed.
I haven't the unit to hand so I can't check it at the moment.
I'll contact ASAP - and post their comments

Thanks

UPDATE: Just spoken with ASAP and they confirm that (as shown by the arrows on the unit, apparently) they are in "series".
i.e. from tank to first filter, then into second filter and thereon to the pump/engine.

Certainly looking at the unit when it arrived that was what it looked like to me (from memory).

I'm interested to hear if anyone has indeed a unit that filters "in parallel" - which seems to defeat the need for two filters (in my ignorance) :confused:
 
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scottie

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Ah! :(
If I have that set-up I'll be very annoyed.
I haven't the unit to hand so I can't check it at the moment.
I'll contact ASAP - and post their comments

Thanks

UPDATE: Just spoken with ASAP and they confirm that (as shown by the arrows on the unit, apparently) they are in "series".


I'm interested to hear if anyone has indeed a unit that filters "in parallel" - which seems to defeat the need for two filters (in my ignorance) :confused:

If it had a change over valve allowing you to remove and replace a choked one then it would be extremely useful!
 

pvb

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Ah! :(
If I have that set-up I'll be very annoyed.
I haven't the unit to hand so I can't check it at the moment.
I'll contact ASAP - and post their comments

Thanks

UPDATE: Just spoken with ASAP and they confirm that (as shown by the arrows on the unit, apparently) they are in "series".
i.e. from tank to first filter, then into second filter and thereon to the pump/engine.

Certainly looking at the unit when it arrived that was what it looked like to me (from memory).

I'm interested to hear if anyone has indeed a unit that filters "in parallel" - which seems to defeat the need for two filters (in my ignorance) :confused:

I think the moulded arrows on the housing merely identify which are inlets and which are outlets.

ASAP list the single-element filter (their part number 302001) as having a max flow rate of 45 LPH, but say the twin element unit (part number 302009, as you have bought) has a max flow rate of 90 LPH. The only way it could have double the flow rate is if the filters are in parallel.
 

Lodesman77

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Is this the same item ? It has a flow diagram that appears to show a parallel flow...

https://www.inlinefilters.co.uk/Filters-Fuel/Housings/Complete/FDE-5874010

Or this one that looks similar with an inline flow?

https://www.inlinefilters.co.uk/Filters-Fuel/Housings/Complete/FDE-5845B520

ASAP site does not show manufacturers part numbers (that I can see) but if you're in contact with ASAP they could confirm?


Alternative version with glass bowl??

https://www.ebay.co.uk/itm/Case-Int...456416?hash=item2ef943a860:g:3nEAAOSwQItUIzuO
 
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Robert Wilson

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Sadly the 'sales person' you spoke to might not have been the 'expert' you expected. pvb sounds to be spot on there.

I guess that your engine is not one of those super refined beasts that require a 2micron filter?!

To give the SP his due he did go away for quite some time to speak to "someone" so I presume it was a tech-bod.

And no, my old Kubota is in no way refined!
In fact, if it wasn't because I can't easily :( reach the aft filter of the existing pair then I would not have looked for the apparently perfect double set-up
 
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Robert Wilson

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Is this the same item ? It has a flow diagram that appears to show a parallel flow...

https://www.inlinefilters.co.uk/Filters-Fuel/Housings/Complete/FDE-5874010

Or this one that looks similar with an inline flow?

https://www.inlinefilters.co.uk/Filters-Fuel/Housings/Complete/FDE-5845B520

ASAP site does not show manufacturers part numbers (that I can see) but if you're in contact with ASAP they could confirm?


Alternative version with glass bowl??

https://www.ebay.co.uk/itm/Case-Int...456416?hash=item2ef943a860:g:3nEAAOSwQItUIzuO
Thank you.
Definitely not the first one. I paid c.£65, not the £219 as listed there.
The second one doesn't have a "flow" diagram, so I can't tell.
The ebay one may well be similar, but again, no flow diagram. I wish I'd seen it 'though - £28 WITH a glass bowl :(

I'll get in touch with ASAP tomorrow (email or letter) and see what they are prepared to put in writing.

Watch this space!!
 

black mercury

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The double cav type filter has a gallery in the top aluminium housing that supplies both filters at the same time, they are in parallel. They are usually fitted to engines over 100hp, or to increase service life of the filter. You can also get a triple filter housing. To have two filters in series you would need to install two single filter housings with a fuel line going out of one and into the other.
 
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