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Cat vs racor fuel filter

22K views 38 replies 17 participants last post by  BIOTEC 
#1 ·
Which is better and why? if I put an adapter on my truck with a cat filter am I going to lose my water separation? Or is water always going to settle to the bottom?
 
#2 ·
We need this as a sticky, gets asked a lot. But its always a good discussion. Racor is best for stock, 7 microns nominal 65% 65GPH I believe. But with the adaptor you can run a better filter that filters more and have higher flow rates. CAT filter is 2 microns absolute at 99%, but it doesn't have a water drain. Also remember that these filters were designed for slow accelerating engines with multiple filters, not the Duramax which can drain the rails and filter, pulling the water out of the bottom of the filter. There is also the Donaldson Fuel Water Separator, 3 microns absolute 99% with a drain and option to add a clear fuel bowl. This is the setup I run and have no issues. The CAT and Donaldson are rated at 95GPH I believe.

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#7 ·
Great info man! I plan to add an air dog and I love the idea of the Donaldson with the water bowl, but I also heard the Donaldson you couldn't push through the filter it could only be sucked through. have you heard this? I've never drained mine and found water believe it or not! Seems weird consistent ing Georgia is more humid than the devils a$$ haha.
 
#3 ·
if your running a lift pump then draining the rails shouldn't be a problem
 
#5 ·
Good topic.

LB7 launches and we’re amazed. Then filter $hock hit$ when it’s time for a new Air or Fuel filter. $50-$60, and neither lasts very long.

Before long, the ‘Injector Saga’ begin$ and we start focusing on the filtration and chasing the cau$e. But $50+ a pop for a filter vs $4k injectors? Hard to take when it’s only $15-$20 for a new Cat filter on the tractor, and twice the media size. The chase is on for an adapter.

Early 2009, the new acDelco filter solution launches. Hard to find, we (users) were educating the Dealer Parts on it’s existence and bulk orders followed;

It’s a highly porous synthetic glass microfiber coalescing media, and unlike the typical pleated filter, with 90-95% of its volume being void, or open, it has a higher surface area available to hold more contaminants, yet it maintains a low pressure drop.
4 micron AND 99% emulsified water removal. But the expen$e! Still worth the outlay, better particulate filtration/water removal and it lasts twice as many miles as the plain pleated filters.

Next we find the acDelco source is Racor and a new door opens to acquire the filter at almost half the price.

Wix (Napa) joins the Fram/Purolator crowd and ends it’s viability for a fuel filter as it changes it’s design and starts producing the inferior plastic filter which can bypass when clogged (defeats the filter purpose).

As the adapter chase progresses, now we’re down to two choices; Racor’s Coalescer filter or the Adapter to Cat/Donaldson.media.

Coalescer Pros;
99% emulsified water removal, 4 micron particulate, with virtually no pressure drop.
Coalescer Cons;
At $35, it’s still more than the Cat,
Debatable conflicting reports as to 2 or 4 micron, absolute or nominal, in it’s rating. We find both sourcing from Racor. Cat proponents have somehow latched onto data stating the Coalescer as 7 microns absolute, then nominal…no backup to this source, but it spreads.

Cat/Donaldson Pros;
A bit better particulate filtration (2-4 micron absolute), cheaper in price.
Cat/Donaldson Cons;
Initial adapter price,
Higher pressure drop, debatable adverse effects to CP3, shortening lifespan.
No water removal without addition of separator.

Adding a lift pump overcomes the pressure drop and CP3 strain, but adding to the conversion cost. Once past a certain tune level, it would’ve been added anyway, but far greater numbers of owners will never see those levels in their DD.

Even with the added separator, how does it measure up to emulsified water removal? Studies show this to be a greater threat than particulates smaller than 4 microns.

How many miles would you have to drive (using the cheaper media) to recoup the cost of the adapter and water separator?
 
#10 ·
Good topic.

LB7 launches and we’re amazed. Then filter $hock hit$ when it’s time for a new Air or Fuel filter. $50-$60, and neither lasts very long.

Before long, the ‘Injector Saga’ begin$ and we start focusing on the filtration and chasing the cau$e. But $50+ a pop for a filter vs $4k injectors? Hard to take when it’s only $15-$20 for a new Cat filter on the tractor, and twice the media size. The chase is on for an adapter.

Early 2009, the new acDelco filter solution launches. Hard to find, we (users) were educating the Dealer Parts on it’s existence and bulk orders followed;

4 micron AND 99% emulsified water removal. But the expen$e! Still worth the outlay, better particulate filtration/water removal and it lasts twice as many miles as the plain pleated filters.

Next we find the acDelco source is Racor and a new door opens to acquire the filter at almost half the price.

Wix (Napa) joins the Fram/Purolator crowd and ends it’s viability for a fuel filter as it changes it’s design and starts producing the inferior plastic filter which can bypass when clogged (defeats the filter purpose).

As the adapter chase progresses, now we’re down to two choices; Racor’s Coalescer filter or the Adapter to Cat/Donaldson.media.

Coalescer Pros;
99% emulsified water removal, 4 micron particulate, with virtually no pressure drop.
Coalescer Cons;
At $35, it’s still more than the Cat,
Debatable conflicting reports as to 2 or 4 micron, absolute or nominal, in it’s rating. We find both sourcing from Racor. Cat proponents have somehow latched onto data stating the Coalescer as 7 microns absolute, then nominal…no backup to this source, but it spreads.

Cat/Donaldson Pros;
A bit better particulate filtration (2-4 micron absolute), cheaper in price.
Cat/Donaldson Cons;
Initial adapter price,
Higher pressure drop, debatable adverse effects to CP3, shortening lifespan.
No water removal without addition of separator.

Adding a lift pump overcomes the pressure drop and CP3 strain, but adding to the conversion cost. Once past a certain tune level, it would’ve been added anyway, but far greater numbers of owners will never see those levels in their DD.

Even with the added separator, how does it measure up to emulsified water removal? Studies show this to be a greater threat than particulates smaller than 4 microns.

How many miles would you have to drive (using the cheaper media) to recoup the cost of the adapter and water separator?
So which one are you saying is better? I bought mine with 40000k on it and the guy was using wix soon as I got the truck changed to racor. So hopefully the wins didn't let to much trash through even though my injectors are the quietest injectors iv every heard. I also run diesel clean in every tank or optilube xpd which by the way makes your injectors smooth and quiet sounding while picking up a 1.5 mpg increase in my truck. I also thought you wanted a DEmulsifier not a Emulsifier?
 
#8 ·
I was also thinking about filter cost as well since I don't have an air dog yet iv been changing my racors every oil change which is 7500 for me
 
#13 · (Edited)
Miles are not a good comparison for use, gallons run would be better.

Primarily all towing miles, my MPG avg is low. Keeping up with gallon usage instead, with the exception of 1 or maybe 2 times with a bad tank of fuel, I see a average life cycle of 1150-1200 gallons with the Racor.

(Do the math with Your MPG factor)
That puts me in the 12-12.5k mile range, Far better than the 7k miles with the Wix (or similar) media.
At those rates (1200 gals), a DD could well see 20+k miles on a Racor. If you're changing the Racor at 7500 miles, that would equate to 6.5 MPG, bad fuel, or changing early with 35-40% life still left.


....I also thought you wanted a DEmulsifier not a Emulsifier?
As a fuel additive, yes. The Racor filter removes Emulsified water.

I'm kind of lost on the post. Is the Cat better or Racor? You want the (best) absolute micron also right? Or is the Racor better since it displaces water? ‘cause I thought water was what you didn't want.
That’s the dilemma. One is better at particulate filtration, the other with Water (yet it’s micron limit isn’t shabby either). Which do you choose?


.

.
.
Another side to the debate?
"Is there really any water to worry about in Diesel?"
 
#9 ·
Hook'em Horns post #5 just stated the actual facts:thumb
 
#11 ·
I'm kind of lost on the post is te car better or racor you want the absolute micron also right or is the racor better since it displaces water cause I thought water was what you didn't want
 
#12 ·
Like everything else it's something of a compromise. Yes the Cat is probably a better particulate filter but the Racor is definitely a better water filter. A Racor engineer was quoted on this forum stating that the Racor is 98.6% efficient at 4 um. Absolute efficiency is 98.7%, by the way, which is an almost meaningless difference. It seems to be an established fact that the particulate size to really worry about is 4 um and above. So I've done a bunch of research and decided for that for myself I'm happier with the Racor. The Donaldson 553203 mentioned above appears to be a very good filter but the water separation efficiency is only rated at 95% and you need the adapter to use it on the OEM filter head.

The reason I believe the Racors get a bad rap is because the pre-2009 versions deserved a bad rap and there's a lot of carryover from that.

If and when I get a lift pump I will add a Cat and keep the Racor.
 
#14 ·
Good deal man I'm doing exactly what u said at the very end of your paragraph now what's better fass or air dog haha
 
#16 ·
Why were racors so bad pre 09
 
#17 ·
I know my buddy's dads business has an 02 lb7 dually it got a pre filter system the day they bought it. which they bought it new as every work truck they have it has 423000 miles as of last month and has not had one injector nor pump installed.
 
#19 ·
So you can pump through I Donaldson I read that you can't pump through them maybe on madjackracingsynthetics.com I think
 
#20 ·
I have never heard that and in fact I just looked on their page and it says that the P553203 is a direct replacement for the FWS on the Fass Pumps. So I would doubt you would have problems pushing though it.
 
#21 ·
But wouldn't the fass be sucking through any filter hooked to it and it would be pressurizing any filter hooked to the filter head
 
#22 ·
How bout this would cat by any chance make a 2 micron filter with a water drain what I was planning on doing was putting a Donaldson set of filters on my lift pump or a set of cats and leaving my racor on my filter head
 
#23 ·
Gah I wished they'd just put three brand new injectors on a test bench with a Donaldson a car and a racor and see which one lasts longer haha
 
#24 ·
Donaldson makes "CAT" filters
 
#27 ·
I run the coalesor... Heard to many nightmare stories about cat adapters and no lift pump. I have not had any issues with the coalesor and have been running them for about 3 years now. I just buy 3 at a time and usually cost me about 33 bucks a filter.
 
#30 · (Edited)
Stock: Donaldson P550833 4 micron absolute Emulsified H2O Efficiency: 95 Percent
Adapter: Donaldson P553203 3 micron absolute Emulsified H2O Efficiency: 95 Percent

https://dynamic.donaldson.com/WebStore/search/cross_reference.html

Done!


C20ELEPHANT said:
...
 
#34 ·
Donaldson fuel filter #P553207. Ebay or Amazon, $18 to $20 bucks. Clear sight glass, about $15. Space your filter headd out 5/8 of an inch. This is a tall filter.
 
#36 · (Edited)
To my understanding the Donaldson p551313 is a direct replacement for the cat 1r-750. I use the p551313 on my lift pump, I get them for just under $7 a piece. If you don't have a lift pump I would advise against the cat adapter unless you get the filter with a water seperator like Malibu SS suggested.

Also the best buy I found on the factory filter is the racor filter from Dmaxstore...just under $30.
On my lift pump I have a Baldwin BF1258 water seperator, I get them under $13 apiece.

So just to clarify I have a fass titanium 150 with a Baldwin BF1258 water seperator, Donaldson p551313 fuel filter, and the racor in the stock location. In the event I get bad fuel I can change all 3 for about $50. Usually I change the stock filter half as often as the ones on the lift pump. And I always have a complete set behind the back seat, and a few sets at home.👍
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#37 ·
Racor, Donaldson and Baldwin available from B-Line filters in Odessa Tx.
Good people to deal with, they also sell or can get adapters for frame and/or remote mount.
Last Racor I bought from them was around $28-29.
The major killer for injectors is water.
Just don't use a Wix, ruined a set of injectors, junk filters.
I run the Donaldson with clear bowl plus a Cummins water filter on my diesel motor home and it is all mounted after the pump, separates the water and gives you the ability to monitor water content and algae.
 
#38 ·
Water seperator should be before the pump, fuel should be pulled thru it not pushed...that only applies to the water seperator, the fuel filter can be on the positive pressure side of the pump.

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