How often do you change Racor Filters

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So, here is a question for those with vacuum gauges. Why do some of you change the filters when the gauge is not even close to indicating that a change is necessary? Kinda obviates the need for the gauges, doesn't it? I don't have Racors. I have Davcos, the filters of which are changed when the fuel in the clear top portion of the housing begins to approach the top. Simple, no gauges required, no guesswork, no changing filters just in case, only when necessary.
 
I run day tanks and have dual Racors for each engine. I have probably changed those filters at 18-24 month intervals, although the vacuum gauges have not indicated it as necessary.

My day tanks are filled from the fuel polisher only. The filter on that is in the pic below. The gauge for it was only about half way to the red line, so on that basis it did not need changing. But I figured why not do it. Sure, it does not look all that great, but that is after 7.5 years and 9,560 gallons of fuel!


:flowers:Our temperments are vasty different!! I would not leave the harbor knowing the filter was in that condition.:socool: Just looking at that and reminiscing on grumpy water has me in a uncomfortable level of sweat! However, I am sure you and others can cope with knowing running a single smaller yet, adequateRaycore for a smaller boat/diesel, gives such cause. Hence, the small dollars involved and the established schedule will be understood.:dance:
 
So, here is a question for those with vacuum gauges. Why do some of you change the filters when the gauge is not even close to indicating that a change is necessary? Kinda obviates the need for the gauges, doesn't it? I don't have Racors. I have Davcos, the filters of which are changed when the fuel in the clear top portion of the housing begins to approach the top. Simple, no gauges required, no guesswork, no changing filters just in case, only when necessary.

It also depends on the engine manufacturer's lift pump. Some models such as the Cummins C series don't tolerate a lot of vacuum. Check the engine specifications page for maximum allowable lift or vacuum at the lift pump. Make sure you calculation is based on a nearly empty fuel tank.

Ted
 
back in the 80s, when we always got fuel with lots of dirt, water, etc, it was imperative to change your filters on a strict regimen, one year or 1 to 200 hrs, whichever came first.
Then we had the mandated switch to low sulfur diesel (LSD) and suddenly changing filter frequently was no longer necessary, unless you had some other source of filth in your fuel system. With the next change, to ULSD, filter changes any more frequently than when your bowls show crud, your vac gauges reach high readings, or your engines stop reaching higher rpm became overkill.
 
Our temperments are vasty different!! I would not leave the harbor knowing the filter was in that condition.

Al

The filter Brian shows is from his day tank filter system if I'm reading his thread correctly. It looks pretty good for 7 years and nearly 10,000 gallons. Plus no blockage as indicated by the vacuum gauge.

Koliver's post says a lot. Today's fuel as compared to a decade or more ago really make the difference. We're lucky, our tanks are new enough that no high sulfur fuel has intruded and the filters are remarkably clean after a few thousand gallons, mostly Alaska fuel to boot!
 
When the vacuum gauge says to. Every oil change I drain the bowl to remove water and sediment, I have a dual filter setup.
 
I change my racors at about 250 hours or so, or once a year, whichever comes first. They are usually pretty clean, (though not as clean as Jleonard's...that element looks new) and don't really need changing. I just do it out of force of habit I guess. My stupid vacuum gauges don't have drag needles, so they aren't much use unless I climb down into the ER with the engines running pretty hard, which I do occasionally but not often enough. When I check them they are always right on zero. I've thought about changing to ones with drag needles, but it always falls to the bottom of my to do list.


On the other hand, I seldom change the filters on my engines. I prefer to run 10 micron elements in my racors and monitor them closely. The racors are easy to change, available everywhere and cost $10. The on engine filters take more time, are messier, hard to find and cost $20 each. This thread made me feel guilty about that though so I looked back in my maintenance log to see when I last changed them. It was August of 2014.


So I changed them tonight. After 5 1/2 years, 750 hours, they were super clean and there was no grime on the paper towels I used to wipe out the inside of the housings.
 
TBH, I change mine probably too often. We do two big trips a year. And I change them before each trip. I do about 200 hours a year so that would be every 100 hours.

Also we keep talking hours. It really has nothing to do with hours. It has everything to do with how much fuel has gone through them. 100 hours for me at 20 gallons an hour. Also, my engines pump about 4 times more than they use. So not onlly is the fuel getting polished, that means about 8000 gallons goes through them every 100 hours.
 
If you are using your boat a great deal i.e. cruising I suggest the following. Install a vacuum gauge with telltale needle on the top of each secondary filter. You will know when the filter is starting to plug us as the vacuum will increase. You will have advance notice. Install a pressure gauge on the output of the secondary filter.
 
When the vacuum gauge right there at the helm starts to rise. That was once several years on my trawler, and no black slime either. And I do not let a filter sit on standby soaked in fuel but rather shift throughput once in a while to ensure all is well should I have to swap while underway.
 
I change at 250 hours or when the gauge is in the top half of yellow.

I always use a maintenance dose of biocide (Biobar Jr) at each fill. My previous boat had under its first owner developed badly fouled tanks. It was a nightmare. Never again. Note that Valspar fuel has a biocide already in it so if you get Valspar occasionally there’s no reason to add additional biocide. If you haven’t been using biocide, have your tanks professionally cleaned before starting.

Finally, I use 2 micron filters even though Yanmar specs 30 micron. This started when I was caught at night mid-Gulf Stream with a Racor that looked fine but the on-engine Yanmar filter was clogged. Somehow the Bahamian fuel had something fine enough to get past 30 microns but not the 5 micron on the Yanmar filter. Changing that filter in a rolling sea at 3AM was another “Never again”.

I would not recommend this for someone with big engines. I use 4gph and the Racor 500 is rated for 60GPH. So it has lots of extra capacity for me. For the first year I carefully monitored the pressure reading and it was no higher with the 2 micron than it had been with the 30 micron. An advantage is that I now only change the expensive Yanmar filter ever two years. The 2 micron Racor is finer so catches everything first.
 
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I change at 250 hours or when the gauge is in the top half of yellow.

I always use a maintenance dose of biocide (Biobar Jr) at each fill. My previous boat had under its first owner developed badly fouled tanks. It was a nightmare. Never again. Note that Valspar fuel has a biocide already in it so if you get Valspar occasionally there’s no reason to add additional biocide. If you haven’t been using biocide, have your tanks professionally cleaned before starting.

Finally, I use 2 micron filters even though Yanmar specs 30 micron. This started when I was caught at night mid-Gulf Stream with a Racor that looked fine but the on-engine Yanmar filter was clogged. Somehow the Bahamian fuel had something fine enough to get past 30 microns but not the 5 micron on the Yanmar filter. Changing that filter in a rolling sea at 3AM was another “Never again”.

I would not recommend this for someone with big engines. I use 4gph and the Racor 500 is rated for 60GPH. So it has lots of extra capacity for me. For the first year I carefully monitored the pressure reading and it was no higher with the 2 micron than it had been with the 30 micron. An advantage is that I now only change the expensive Yanmar filter ever two years. The 2 micron Racor is finer so catches everything first.

I agree and the way you're using the 2 mics makes perfect sense. When I bought my boat it had 2M filters on it, but the fuel was rather old and had a lot of asphaltanes in it. So of course after a bumpy passage I started to get fuel starvation on one side. Change filter, proceed. But it led me to 'you better clean those tanks'. It turns out I had NO water in either tank which was a blessing. Now that the tanks are pretty clean, I use 10M filters and the 6M on engine secondaries do the rest.

Ken
 
I use a Baldwin 12-micron filter for my engine-mounted filter on my 315 HP Yanmar engine and 2-micron elements in my Racor 500 filter bodies rated at 60 GPH. The engine at speed sucks 21 GPH (returns about 12) which means I might actually be getting a bit of the advertised turbine action in them. No sign of water in five years on my bottom draw tanks. Power Service Kleen and Biobor always.
 
TBH, I change mine probably too often. We do two big trips a year. And I change them before each trip. I do about 200 hours a year so that would be every 100 hours.

Also we keep talking hours. It really has nothing to do with hours. It has everything to do with how much fuel has gone through them. 100 hours for me at 20 gallons an hour. Also, my engines pump about 4 times more than they use. So not onlly is the fuel getting polished, that means about 8000 gallons goes through them every 100 hours.

Wow! The Coot only consumes less than 2 gallons an hour, yet changes filters once a year.
 
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Two Cummins 6bt5.9M 210 HP. Runs at 1500 rpm and 3.5gpm combined. Have Changed the 900 racor on each engine twice in 2500 hrs. The vac gauges stay in the green. Filters were sightly dirty on the two changes. Bowls clean, no water. Change engine fuel filters every 500 hrs. My guess is to days fuels are clean. I use biocides every other fill up. I rotate biocide products, because I read they are different.
My 2 CENTs FWIW.
 
You should rely on the vacuum gauge to drive replacement, that's the ultimate arbiter for filter condition. If you need to change filters before using 1,000 gal of fuel, that's a sign of a tank contamination problem. Hours are a less reliable yard stick as it's really a function of how much fuel has passed through the filter, which is different at different rpm.

If you have a polishing system it's conceivable you'd never need to change a filter, but of course you should not leave them in place indefinitely. Having said that, and having changed a lot of filters, I've never seen one deteriorate even those that haven't been changed for years. Every time you change a filter you reduce its efficiency, as a filter traps some dirt, it becomes more efficient. I'm not suggesting anyone violate Racor or engine manufacturer instructions, just pointing out relevant details.

Install a good vacuum gauge, I'm partial to these https://dentmarine.com/

More on vacuum gauges https://www.proboat.com/2012/04/the-vacuum-gauge-tool/

More on filter service https://stevedmarineconsulting.com/fuel-and-air-filter-service-protocols/
 
depends on the micron size, ie, white/brown, or red...clyde
 
It amazes me that anyone actually used a product called "sea foam" or "marvel mystery oil".
Reeks of quackery and snake oil to me.

Is there any actual science behind any of them?

Yes, there is. It's called the placebo effect.
 
A fully clogged filter is good for 0 microns. Can't get better than that.
 
Well, in 8 years on my GB 36, I have not changed my Racors (10 micron) even once and never had the vacuum gauge elevate above zero. I change my on-engine 2 micron filter annually (converted to a screw on, so easy to change) with my annual oil change. I only drive something between 50 - 100 hours per year, and I use Biobar Jr. at each refill, but that has only happened 3 times in these eight years. This is a single Lehman 120, which burns about 1.7 gallons/hour. I bug my mechanics (very well-respected but curmudgenly) about this, but they say there is no need to change if there is no vacuum developing, and the filters do look clean under a flashlight through the bowl. I have no fuel polishing system, which they pooh-poohed because they report the baffles in the tanks pretty much negate the chances of polishing doing anything measureable to the fuel in said tanks. So, I am not advocating any of this, but just saying my guys apparently think it is way overkill. I'm type A enough to question it with them, but do defer to their well-known track record. Whaddya think?
 
And that's pretty much what I said when I asked the question "Why change filters before the vacuum gauge indicates a change is necessary?" Waste of time and money but it's your money to waste. My boat has Lehman 120s which return virtually no fuel. I know the burn rate to be about 3.5 gallons per hour (two engines). Gallons filtered is just simple arithmetic. Last change was at about 1,600 gallons. Filter is 10 microns.
You should rely on the vacuum gauge to drive replacement, that's the ultimate arbiter for filter condition. If you need to change filters before using 1,000 gal of fuel, that's a sign of a tank contamination problem. Hours are a less reliable yard stick as it's really a function of how much fuel has passed through the filter, which is different at different rpm.

If you have a polishing system it's conceivable you'd never need to change a filter, but of course you should not leave them in place indefinitely. Having said that, and having changed a lot of filters, I've never seen one deteriorate even those that haven't been changed for years. Every time you change a filter you reduce its efficiency, as a filter traps some dirt, it becomes more efficient. I'm not suggesting anyone violate Racor or engine manufacturer instructions, just pointing out relevant details.

Install a good vacuum gauge, I'm partial to these https://dentmarine.com/

More on vacuum gauges https://www.proboat.com/2012/04/the-vacuum-gauge-tool/

More on filter service https://stevedmarineconsulting.com/fuel-and-air-filter-service-protocols/
 
Well, in 8 years on my GB 36, I have not changed my Racors (10 micron) even once and never had the vacuum gauge elevate above zero. I change my on-engine 2 micron filter annually (converted to a screw on, so easy to change) with my annual oil change. I only drive something between 50 - 100 hours per year, and I use Biobar Jr. at each refill, but that has only happened 3 times in these eight years. This is a single Lehman 120, which burns about 1.7 gallons/hour. I bug my mechanics (very well-respected but curmudgenly) about this, but they say there is no need to change if there is no vacuum developing, and the filters do look clean under a flashlight through the bowl. I have no fuel polishing system, which they pooh-poohed because they report the baffles in the tanks pretty much negate the chances of polishing doing anything measureable to the fuel in said tanks. So, I am not advocating any of this, but just saying my guys apparently think it is way overkill. I'm type A enough to question it with them, but do defer to their well-known track record. Whaddya think?

Beware curmudgeonly mechanics, I find many stopped learning long ago. Hopefully yours are different.

To dismiss all fuel polishing systems because baffles inhibit fuel movement is simply incorrect (see aforementioned comment regarding curmudgeonly mechanics). A properly designed and installed polishing system draws fuel from the bottom of one side of a tank and returns it to the bottom of the other side of the tank, thereby promoting movement of fuel across the tank bottom, and through baffle limber holes.

If your vacuum gauge has never moved, I'd test it, I occasionally encounter gauges that do not work. You can do this by slowly closing the fuel tank supply valve while the engine is idling, you should see the gauge begin to move almost immediately.

Clearly what you are doing seems to work, but you can overdoes on biocides. In your low use application, I'd be using a fuel stabilizer rather than a biocide. If you have no water in the tank (can you drain water?), you can have no biological growth, making the use of a biocide like BioBor unnecessary.

While I'm an advocate of condition based maintenance, i.e. changing filters when they need it rather than based on the calendar, 7 years is a long time to go without replacing a filter. Manufacturers say annually, and I've seen filters go a very long time without being replaced and have not seen deterioration, but I think I'd cap that at 3 years. Again engine and filter manufacturers say annually, but they do sell filters.

I'm curious, why replace your secondary and not primary?
 
Just a quick plug for fuel stabilizer/biocide, I use Pri-D, a gallon lasts forever and I've been using it for years in four of my boats, truck and tractor.
 
Just a quick plug for fuel stabilizer/biocide, I use Pri-D, a gallon lasts forever and I've been using it for years in four of my boats, truck and tractor.

And then there's those of us who use none.
And have no issues either.
 
And then there's those of us who use none.
And have no issues either.

Having owned a boat with fuel-sipping FL120 engines which returned little fuel, large tanks, and that had sat around a lot before I owned it, I would have to say that owners who brag about having no tankage issues and forever clean filters are coming from a whole different experience, or like me, are they blissfully unaware? Let me explain my point of view. People who regularly cruise longer distances than say a local day on the water once in a while have the advantage of running a lot of fresh fuel all the time. I had owned my boat for about 12 years when I joined the Trawlers and Trawlering email list in 1998. There I began to acquire knowledge like it was coming from a fire hose as compared to the information available to me before that. I learned at the knee of Captain Wil about these tankage issues. My four tanks were all bottom draw, but I had been seeing no issues what with changing fuel filters every year. I was always careful to properly dose with Biobor. The 2-mike filters removed were dark but not goopy and there was never any water in the Racor bowls. I, like you thought, "I am among the fortunate few with no issues." However, after reading enougries on the email list I one day took a hand pump and a length of tubing and sampled the bottoms tanks from the deck fill. What came up shocked me because although my sight gauges on all the tanks never showed anything but cherry red clear fuel, what I drew out into my glass quart jars was a murky purple liquid that even after a week never settled out. Since the tanks all "veed" to a point on their inboard sides, and the draw point was an inch or two from the bottom, I can only assume the purple stuff was at the part inaccessible via the bottom draw, until it was shaken and stirred anyway. That was when I installed a polishing system and spent a week changing its filters every four hours of running until they finally came out of the polisher clean. Because I am NOW running 20 gallons an hour through my current engine using 2-micron Racor filter elements from two 75-gallon bottom draw (draws at aft ends) tanks which get tilted well up at the bow in this semi-planing boat, I believe I do not need a polisher, but I continue to use Biobor and an anti-sooting additive. - belt and suspenders.
 
I don’t use any additive either. But I am burning a lot of fuel and I use the boat very often. On top of that, my marina sells Valvtect...so I guess I am using additives when I buy from there. Not enough history on current boat but never an issue with the previous one.
 
Well, in 8 years on my GB 36, I have not changed my Racors (10 micron) even once and never had the vacuum gauge elevate above zero. I change my on-engine 2 micron filter annually (converted to a screw on, so easy to change) with my annual oil change. I only drive something between 50 - 100 hours per year, and I use Biobar Jr. at each refill, but that has only happened 3 times in these eight years. This is a single Lehman 120, which burns about 1.7 gallons/hour. I bug my mechanics (very well-respected but curmudgenly) about this, but they say there is no need to change if there is no vacuum developing, and the filters do look clean under a flashlight through the bowl. I have no fuel polishing system, which they pooh-poohed because they report the baffles in the tanks pretty much negate the chances of polishing doing anything measureable to the fuel in said tanks. So, I am not advocating any of this, but just saying my guys apparently think it is way overkill. I'm type A enough to question it with them, but do defer to their well-known track record. Whaddya think?

"Well, in 8 years on my GB 36, I have not changed my Racors (10 micron) even once and never had the vacuum gauge elevate above zero."
A new perfectly clean filter will read above zero - even removing the filter will read above zero.
There remains some resistance in the lines and fittings for fuel flow even with a new filter.
I would start with why you are not seeing zero vacuum.
 
As I said in my contribution to the thread, I was not advocating an approach, but merely describing my experience so far. I thought Steve D'Antonio's remarks were on the money, and mentioned that I would adopt his recommendations as soon as possible, including testing the vacuum gauge. Great idea.

However, my response was in the form of the "Quick Reply", and it doesn't seem to show up in the conversation. What gives? Apparently I need to post my response at the head of the thread for it to be included? I hope some one will take the time to explain. Thanks. Tim
 
Dual Racor 1000's. I change them every 100 hrs. LOL!!!

I'm in New England and only boat about 5 months out of the year. I work full time, so it's really weekends and a few weeks a summer. I'm lucky if I get 100 hours a year at this point. I change them in the spring when the boat is launched.
 
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