10 micron OR 30 micron for diesel pre-filter

sharpness

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I'm about to buy some spare pre-filters for the Racor 900 series i have fitted and i can't make my mind up wether to go for 10 micron or 30 micron. The engines are Volvo Tamd61a and they have two fine filters (5 micron i think) prior to the injection pump.

Logic tells me the 10 micron for pre-filter would be good as if these were to block, then the engine fine filters should be ok, but if i fitted 30 micron and these were to block then i would most likely have to change the engine fine filters aswell (access not that great, and more hassle to prime etc). Access to the pre-filters is reasonable. Pretty certain the boat is currently fitted with 30 micron for the pre-filter, but do any of you know any reason why i couldn't change to the 10 micron version - i.e issues with fuel flow, or would they block up too easily etc ?

Thanks in advance for any replies.
 
Sharpness,

Not sure of layout of your last chance filters, if as you say you you have tandem 5 micron then you need rock stoppers so previous owner had sizing correct. If you have 10 micron your filter restriction will rise in a trice should you bunker some contaminated fuel.
 
Thank you both for your replies. Looks like an easy decision, will stick with the 30 micron.

For sourcing Racor fuel filters, the best prices i can find are either from ASAP or Phoenix marine solutions. Are there any other suppliers that would be recommended ?
 
Logic tells me the 10 micron for pre-filter would be good as if these were to block, then the engine fine filters should be ok, but if i fitted 30 micron and these were to block then i would most likely have to change the engine fine filters aswell (access not that great, and more hassle to prime etc). Access to the pre-filters is reasonable. Pretty certain the boat is currently fitted with 30 micron for the pre-filter, but do any of you know any reason why i couldn't change to the 10 micron version - i.e issues with fuel flow, or would they block up too easily etc ?
The first thing I would do is check if the engine manufacturer has any recommendation for the primary fuel filter. The second thing to consider is which filter is more easy to change in a lumpy sea and with hot engines. Normally that would be the primary filter. IMHO, a 30micron primary filter would very likely lead to the engine fine filter blocking first before the primary filter which is probably the wrong way round so for that reason, I'd go with 10 micron primary filters and carry plenty of spares. However, as I say, if the engine manufacturer has a recommendation, you have to go with that
 
I'm about to buy some spare pre-filters for the Racor 900 series I have fitted and i can't make my mind up wether to go for 10 micron or 30 micron. The engines are Volvo Tamd61a and they have two fine filters (5 micron i think) prior to the injection pump.

Logic tells me the 10 micron for pre-filter would be good as if these were to block, then the engine fine filters should be ok, but if i fitted 30 micron and these were to block then i would most likely have to change the engine fine filters aswell (access not that great, and more hassle to prime etc). Access to the pre-filters is reasonable. Pretty certain the boat is currently fitted with 30 micron for the pre-filter, but do any of you know any reason why i couldn't change to the 10 micron version - i.e issues with fuel flow, or would they block up too easily etc ?

Thanks in advance for any replies.

On Play d'eau, Racor advised me to use 10 micron, and preferably 2 micron. I was told that whether you use 30,10, or 2, there's no reduction in fuel flow. The argument was simple. If you are going to have a filter blockage at sea, do you prefer changing the Racor or the engine filter? If the latter, you'll probably have to bleed it as well. Your Racors are probably more accessible, easier to change, and don't require bleeding.

As I said, I use 10 micron and have done for years.
 
If you buy from chandlery they will charge a fortune, I change pre filters 3 times a year and used to get them from Volvo agent at £25 each for the same filter in a blue box. Now I get them from http://stores.ebay.co.uk/Hyphose?_trksid=p2047675.l2563 I buy 6 at a time and postage is good, you can collect as well
Why on earth do you change th filters so often.. have you got mucky tanks?
Tempting fate, but mine are almost clean at the end of the whole season .
 
On Play d'eau, Racor advised me to use 10 micron, and preferably 2 micron. I was told that whether you use 30,10, or 2, there's no reduction in fuel flow. The argument was simple. If you are going to have a filter blockage at sea, do you prefer changing the Racor or the engine filter? If the latter, you'll probably have to bleed it as well. Your Racors are probably more accessible, easier to change, and don't require bleeding.

As I said, I use 10 micron and have done for years.
Yes, agree entirely. I've just checked some Cat literature and they seem to recommend 10 micron primary filters as well
 
On Play d'eau, Racor advised me to use 10 micron, and preferably 2 micron. I was told that whether you use 30,10, or 2, there's no reduction in fuel flow. The argument was simple. If you are going to have a filter blockage at sea, do you prefer changing the Racor or the engine filter? If the latter, you'll probably have to bleed it as well. Your Racors are probably more accessible, easier to change, and don't require bleeding.

As I said, I use 10 micron and have done for years.

Piers,

With all due respect Racor are as usual talking complete caca. Racor do not publish Beta ratios so you cannot separate fact from fiction, which is the very reason I avoid them on new installations. However I accept most builders suffer from Racoritis (a form of filteration blindness)

Given up trying to convince people to adopt multi stage filteration, however principal of filtering down in steps 30, 10, 5, 2 etc still applies.

I would expect you to have Fleetguard FS1280 last chance filters. FS1280 is a two pass 20 micron first pass 10 micron second pass filter with 96% efficiency.

Putting a 10 micron primary in front of a 20 micron last chance filter makes no sense whatsoever. As to the comment regarding being easier to change just confirms that Racor people are from the planet zog!

As to Volvo Penta, I was trying to design a super safe multi stage filteration system for Volvo D4/6 with WIF sensor in the primary NOT in the last chance or in the case of common rail 'too late filter'. Filter is VP proprietary only and I wrote asking for the technical spec rather than guess that it conformed to normal Bosch common rail requirements of 2 microns. Reply was that this is 'commercial in confidance'. Ho hum........
 
Piers,

With all due respect Racor are as usual talking complete caca. Racor do not publish Beta ratios so you cannot separate fact from fiction, which is the very reason I avoid them on new installations. However I accept most builders suffer from Racoritis (a form of filteration blindness)

Given up trying to convince people to adopt multi stage filteration, however principal of filtering down in steps 30, 10, 5, 2 etc still applies.

I would expect you to have Fleetguard FS1280 last chance filters. FS1280 is a two pass 20 micron first pass 10 micron second pass filter with 96% efficiency.

Putting a 10 micron primary in front of a 20 micron last chance filter makes no sense whatsoever. As to the comment regarding being easier to change just confirms that Racor people are from the planet zog!

As to Volvo Penta, I was trying to design a super safe multi stage filteration system for Volvo D4/6 with WIF sensor in the primary NOT in the last chance or in the case of common rail 'too late filter'. Filter is VP proprietary only and I wrote asking for the technical spec rather than guess that it conformed to normal Bosch common rail requirements of 2 microns. Reply was that this is 'commercial in confidance'. Ho hum........

You've got me thinking, Latestarter. The engine fine filters on Play d'eau are the FF5285. Doing a quick google shows this to be a 10 micron - it that correct?
 
. As to the comment regarding being easier to change just confirms that Racor people are from the planet zog!
What's not easy about changing a Racor type turbine filter, especially the dual type? Certainly far easier than changing a fine filter on a hot engine and trying to bleed it with the boat being chucked around in a lumpy sea. Agree though that ideal would be a multi stage primary filtration process but I've never seen this on a mainstream production boat although I'd happily pay extra money for it
 
What's not easy about changing a Racor type turbine filter, especially the dual type? Certainly far easier than changing a fine filter on a hot engine and trying to bleed it with the boat being chucked around in a lumpy sea. Agree though that ideal would be a multi stage primary filtration process but I've never seen this on a mainstream production boat although I'd happily pay extra money for it
I was wondering if the chosen design is something to do with the amount of fuel being used. We arent talking about industrial clobber running 10,000 hours...
Most boats probably dont do a hundred hours a year.
 
You've got me thinking, Latestarter. The engine fine filters on Play d'eau are the FF5285. Doing a quick google shows this to be a 10 micron - it that correct?

Piers,

FF5285 is automotive filter unlike marine FS1280 with water separator. I would be relaxed regarding use of FF5285 inexpensive, well under a tenner and I expect you chage them frequently. FS1280 is a tad more expensive at just over a tenner.

My issue with using a primary which is too small is that it will plug quickly. Racor statement regarding restriction with 'clean' filters is blindingly obvious. I would expect a decent system regardless of micon rating to represent a restriction of under 3 inches Hg when clean. Engine will tolerate at least 10 inches and possibly 15 inches Hg before motor starts to stutter. If your primary is too fine, filter life will far shorter. What you need is a filter/filters to protect your last chance filters from boulders, crud and muck WITHOUT hitting more than 10 inches of Hg. As to last chance filters plugging before primary, it will never happen if primary filteration in good shape. Stuttering engines always happens at the wrong moment.

No such thing as too much filteration.
 
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Why on earth do you change th filters so often.. have you got mucky tanks?
Tempting fate, but mine are almost clean at the end of the whole season .

Cause when I bought the boat the agent (won't mention names) came from totnes begins with s ends with an o and has imc in middle. They filled the brand new tanks with diesel on one side and 8 inches or crud, sh@t in bottom in the starboard tank, have got rid of most but I'm still getting muck out 4 yrs later. Have tried to empty tank and ensure only quality fuel goes in, even put a pump sucking out fuel through a filter and back in, which got rid of most,
 
Cause when I bought the boat the agent (won't mention names) came from totnes begins with s ends with an o and has imc in middle. They filled the brand new tanks with diesel on one side and 8 inches or crud, sh@t in bottom in the starboard tank, have got rid of most but I'm still getting muck out 4 yrs later. Have tried to empty tank and ensure only quality fuel goes in, even put a pump sucking out fuel through a filter and back in, which got rid of most,

Might it be possible to use a mobile fuel polishing company to resolve it once and for all?
 
Might it be possible to use a mobile fuel polishing company to resolve it once and for all?

All that is required in these instances is to add a a 'gatekeeper' in front of the Racor, say FS 1218. FS 1218 will absorb twice it's own weight of crud before representing serious restriction, expensive at around £35 a pop and may need replacing twice before fuel in tank polished. Drop Racor to 10 micron and with this set up 'last chance' filters will go at least two years before change is required and Racor filter bowl will stay clean. By putting simple but large capacity spin on filter in front of Racor in the unlikely event of the 1218 being overwhelmed with crud change can be made in a trice, far quicker than messing with Racor.

Saves calling in fuel polishing company and you have insured against bukering dirty fuel in the future.
 
Thanks for the info, about 3 yrs ago at SIBS I spoke to a company who were going to call me and make appointment to clean the tanks, I chased them and they made an appointment and didnt turn up. I chased them and they said they would get back to me, and never did that put me back.

Then I made my own filter using an inline pump a swimming pool filter and an air line. Rigged this up out of the sender unit hole and through the pump back into the fuel filler, stirred up by the air line for a few hours. Have to be honest the fuel seems better and I have not had the issues of blocked filters but they are black when changed so its still a cheap thing to do that takes 1 min in a marina rather than do it at sea.

So I still do it.
 
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