Changing Racor & On engine fuel filter?

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Streff

Senior Member
Joined
Oct 13, 2019
Messages
135
Location
USA
Vessel Make
Californian 45 MY
I was sitting in the engine room ready to change Racors and secondary fuel filters and I started thinking maybe I don't need to change them yet on 3208TAs. Last season we only cruised for about 100 hrs last season. The vacuum gauges on the Racors is half way to the yellow section (if that).

What is the experience and recommendations of this forum on that subject?

Manual recommends changing the filters every 200-300hrs or yearly. I was told that the yearly recommendations is a CYA statement.

I never skimp or miss changing oil filters and oil in all vehicles and boats. But in our diesel motorcoah, I may go 18months between fuel filter changes.

I would very much appreciate any input and experiences from the group.

Thank you in advance.

Streff
 
I change mine at 500 hours and use 2 micron on twin Detroits.
 
I don’t change them nearly that often. But mine don’t get dirty either.
 
Your vacuum gauges tell you when to change the primary Racors. Half way to yellow means they are half way to used up. You have answered your own question. Folks without gauges change filters on a schedule that fits their requirements.
 
Whatever makes you comfortable?

I change my filters, all of them yearly, after about 100 hours (700Nm) We travel a long ways from home and I hate to think of changing filters in a gale on our lakes. Filters do not get dirty while sitting idle, they do not "time out." If the primary is building up a lot of fuzz and strings in its see-through bowl, think hard about it, regardless of the hours, vacuum gauge readings, etc. Keeping your tanks quite full slows you down just a bit, but prevents some of the sludge from getting loose and into your system.
 
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You can buy and install a vacuum gauge on or near your filter housing that will show and record the vacuum cause by restrictions in the filter. Once you notice a performance problem, you will know it's time to change the filters.

Since you now have a record of the vacuum level that cause the performance problem, just change your filters before the gauge gets to that level.

Racor sells the gauge.
 
I had dual Racors for my primaries. I phoned Racor and was told that leaving my "backup" filter full of clean fuel (and not using it) for even 2 years was not a problem. (Switching to the "backup" in the 3rd season).

I changed my "in use" primary once per year which usually averaged about 200 hours. I also had a vacuum guage and have never seen the vacuum rise into the red.
So, my guess would be if your bowl looks clean, and your vacuum level is not rising, with only 100 hours you can leave them for a while yet. Depending on your hours, maybe the whole season this year.
 
Thank you all for the thoughtful input. As usual some posts trigger more questions. All in pursuit of knowledge. I will probably wait another 25-50hrs or so before replacing racors..right before taking off on our planned longer trip out. In terms of the secondary filters, i would think they are stay on for another 100 hrs.. Not sure yet.

Back to the racors. The bowls definitely show a smattering of black deposits. I am not sure what that the deposits indicate in terms of racor health?

On another note, when we purchased the boat, I found several new 2 micron racors that were left by the PO. I was advised to install 10micron filters instead. It kinda made sense to me. Racors at 10u then secondary CAT filter which are 2micron. But now, I am wondering if 2micron racors would be OK? Possibly with 2micron racors, secondary filters may not need replacing as often.

As a side note, the last time I was in Vancouver, I changed the oil and took it to a non-profit disposal. They claim that the oil is still good and that they get the oil cleaned/reconstituted then sell it or donate it. Interesting.

Thank you all again for the input.

Streff
 
For more (maybe more than you actually want) info on fuel filtration, I suggest checking out Tony Athens' website sbmar.com under both his "Tony's Tips" and the various forums.
The "gold standard" for fuel filtration would be a multi-stage setup. In a "perfect world" you would start with a "mud" filter of about 30 microns, followed by a second level filtration of 10 microns, with the "on engine" filter being the filter of last resort, and especially if your engine is common rail, a 2 micron filter. Most boaters don't go that far, however, under a setup as described, the on engine filter would probably last a very long time before becoming "a problem".
Several members on TF have said they have had good results using 2 micron Racors. Just be aware that you will have to change them more frequently than the 10 or 30 micron ones.

My thoughts are it depends on your engine and what level of filtration is required. For example, if I remember correctly my OEM on engine filter (Cummins 6BTA) was rated at 20 microns. Normally my Racor was a 10 micron filter and for $30 I just changed it annually (around 200 hours). I cut apart both Racors and on engine filters (and never found any major "plugging") to check how things were going.
Another huge factor is how clean your tanks (and fuel stored in them) are.
 
I'm one of those who believe in multi stage filtration. 30 micron to 10 micron Racors then to the on engine filters which are 7 micron I believe for the Lehman 120.
I typically change the 10 micron annually, and the others every other season.
The 10 micron elements usually look like the picture below.
I have vacuum gages but they rarely show anything but I am just a creature of habit and believe in prevention.
The other pic shows the multi stage Racor setup.

Using the 2 micron elements should be ok, but if they start to clog up and give you trouble just switch to 10 micron.
And whatever you do learn how to change them yourself and have the tools handy in case you need them in a hurry.
 

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Racor says their aquablock coatings on the filters have a life, measured in calendar months not engine run hours. And for this reason you should change them yearly and use fresh filters not 3 year old ones. Now that could be a requirement from their sales department to increase sales, I don't know. Keeping the water out of the injection system is mildly important on mechanically injected engines but can be critically important on newer common rail engines. The 30,000 psi pump doesn't like water.
 
I change mine every year regardless of hours, except last year which was a really low engine hour year.

pete
 
I have Racor vacuum gauges built into the T handle. Very convenient.
 
...........
On another note, when we purchased the boat, I found several new 2 micron racors that were left by the PO. I was advised to install 10micron filters instead. It kinda made sense to me. Racors at 10u then secondary CAT filter which are 2micron. But now, I am wondering if 2micron racors would be OK? Possibly with 2micron racors, secondary filters may not need replacing as often.

Streff

When I bought my boat, the PO was using 2 micron Racor filters as well as the 2 micron filter on the engine. I have continued to use 2 micron Racor filters for about 2,000 hours with no clogging problems.

I suppose buying fuel in the USA from mostly high volume sources helps. It's really your choice.
 
I have not heard of an engine-mounted (secondary) fuel filter on 2-micron filtering capacity before. Because my total fuel capacity is only 160 gallons or so, and my typical return rate is 11-12 GPH, and because changing the secondary is both more expensive and troublesome, I use 2-micron in my Racors. The only secondaries I can find for my engine are 10-12 micron.
 
Rich, on my Lehman 120s, I long ago converted the sometimes problematic CAV clamshell filter heads with spin-on capability. In the picture you will see first a Donaldson (#P551615) then a Racor (#S3216S). The Donaldson is three microns. The Racor is two microns. Both, especially, the Donaldson, are much larger than CAV filters. I also installed a Tony Athens sequential filtering system. The first filter is a 20-micron "mud" filter. The second filter is 10 microns. Both are very large. Changing the Tony Athens filters is a breeze. Shut off fuel supply, spin filter off, spin new filter on, open fuel supply valve, open bleeder on filter head until no bubbles (5 seconds), close bleeder, start engine. Much easier and less messy than when I had Racor primaries.

In about 1,000 hours of operating this boat I have never seen ANY water and just a few bits of visible debris. My tanks feed from the bottom rather than from a dip tube. It is my opinion that any boat (many do not) that has the capability to feed fuel from the bottom ought to do so. Any water and crud will continually be flushed through and filtered thus keeping fuel tanks clean.

I also wonder why we even bother with on-engine filters. Set up a 20/30-10-2 micron filter assembly, all with vacuum gauges, and eliminate the on-engine filters. If I had a common rail engine I would do this. In fact, I am wondering why I shouldn't do so for my Lehmans.
I have not heard of an engine-mounted (secondary) fuel filter on 2-micron filtering capacity before. Because my total fuel capacity is only 160 gallons or so, and my typical return rate is 11-12 GPH, and because changing the secondary is both more expensive and troublesome, I use 2-micron in my Racors. The only secondaries I can find for my engine are 10-12 micron.
20210411_170438.jpeg20210201_142145.jpeg
 
Rich, on my Lehman 120s, I long ago converted the sometimes problematic CAV clamshell filter heads with spin-on capability. In the picture you will see first a Donaldson (#P551615) then a Racor (#S3216S). The Donaldson is three microns. The Racor is two microns. Both, especially, the Donaldson, are much larger than CAV filters. I also installed a Tony Athens sequential filtering system. The first filter is a 20-micron "mud" filter. The second filter is 10 microns. Both are very large. Changing the Tony Athens filters is a breeze. Shut off fuel supply, spin filter off, spin new filter on, open fuel supply valve, open bleeder on filter head until no bubbles (5 seconds), close bleeder, start engine. Much easier and less messy than when I had Racor primaries.

View attachment 117069View attachment 117070

Thanks for the information. Your setup is excellent, and that FL120 gleams. I ran 2-Micron Racors and changed my twin FL120s to spin-ons as you did. Ran 'em that way for twenty nine years. My current engine is a VERY different animal, a 315HP turbo with a monstrous throughput compared to the FLs, and I am doing fine keeping VERY clean fuel and tanks with the 2-mic Racors and whatever capacity the engine spin-on has. It would be far from simple to change this spin-on because it has a built-in water alarm, something I added to my Lehmans and my generator with the special bowl and sensors you can get from Parker. I consider that the engine-mounted filter is just along for the ride (except for the water alarm) and that all real filtration is handled by the Racors.
 
The pressure gauges work just fine and show you when to change the filter. The issue with them is that you need to go see them when the engine is working and preferably working hard (above your normal cruising RPM) when the engine is turning around the most amount of fuel in order to asses the actual filter condition.
0-5000psi_Kobelt-e1601097759256.png

AcrossOceanSystems.com has interesting new solution especially designed for Racor Filters that replaces the T-Handle with NMEA2000 pressure sensor that reports to your MFD the vacuum building up in the system when the filter starts to get plugged in.
You can read more on Panbo.com:

At the moment they offer free replacement T-Handle designed to accommodate the NMEA2000 sensor and provides incredible easy installation when you purchase one of their sensors.

The sensors are with standard 1/4" NPT so they can be installed on any type of filtration system, not only on RACOR filters.

Here are the recommended negative pressure values from Racor:
Safe zone (green or no color)
from 0 to -7 in/Hg or from 0 to -3.5 PSI



Warning zone - time to replace filter
from -7 in/Hg to -10 inches of Hg from -3.5 PSI to -5PSI .



Danger zone (red)
Negative pressure more than -10 in/Hg or -5 PSI could cause the engine to stall.
 
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GIGO

Back in the day running the ICW, around the Great Loop, going to the Bahamas in our big DeFever, at the high volume marinas, we would pump directly to the tank. At the sketchy marinas we would start by putting a little diesel in a clean white bucket. Stop and look for crud. If we saw crud, we'd pass.

On the loop, we carried an external fuel filter to clean the diesel before it went into the tanks. That kept the racors pretty clean.

Bob Smith suggested 10 micron primaries down to 2 micron secondaries. But since we had our fuel professionally polished in a way the cleaned the crud off the bottom, tanks were then inspected, we ran 2 microns on the primaries as well. Only cleaned the secondaries twice in six years.

We changed the primaries when we changed the oil or when the pressure gauge suggested, or when we were at a marina that would take the filters.

Bob
 
"The pressure gauges work just fine and show you when to change the filter. The issue with them is that you need to go see them when the engine is working and preferably working hard (above your normal cruising RPM) when the engine is turning around the most amount of fuel in order to asses the actual filter condition."

Seawater, true to a point. However, if you have a vacuum gauge with a drag pointer, you can determine the health of the filter at any time including when the engine is not running. Simple, effective and no need for expensive Bluetooth indicators.
The pressure gauges work just fine and show you when to change the filter. The issue with them is that you need to go see them when the engine is working and preferably working hard (above your normal cruising RPM) when the engine is turning around the most amount of fuel in order to asses the actual filter condition.
0-5000psi_Kobelt-e1601097759256.png

AcrossOceanSystems.com has interesting new solution especially designed for Racor Filters that replaces the T-Handle with NMEA2000 pressure sensor that reports to your MFD the vacuum building up in the system when the filter starts to get plugged in.
You can read more on Panbo.com:

At the moment they offer free replacement T-Handle designed to accommodate the NMEA2000 sensor and provides incredible easy installation when you purchase one of their sensors.

The sensors are with standard 1/4" NPT so they can be installed on any type of filtration system, not only on RACOR filters.

Here are the recommended negative pressure values from Racor:
Safe zone (green or no color)
from 0 to -7 in/Hg or from 0 to -3.5 PSI



Warning zone - time to replace filter
from -7 in/Hg to -10 inches of Hg from -3.5 PSI to -5PSI .



Danger zone (red)
Negative pressure more than -10 in/Hg or -5 PSI could cause the engine to stall.
 
I was sitting in the engine room ready to change Racors and secondary fuel filters and I started thinking maybe I don't need to change them yet on 3208TAs. Last season we only cruised for about 100 hrs last season. The vacuum gauges on the Racors is half way to the yellow section (if that).

What is the experience and recommendations of this forum on that subject?

Manual recommends changing the filters every 200-300hrs or yearly. I was told that the yearly recommendations is a CYA statement.

I never skimp or miss changing oil filters and oil in all vehicles and boats. But in our diesel motorcoah, I may go 18months between fuel filter changes.

I would very much appreciate any input and experiences from the group.

Thank you in advance.

Streff
To determine when was time to change filters, while cruising I closed the fuel valve between the tank and the Racor and observed as the vacuum meter needle indicated increasing vacuum. At some point, the engine began to quit and I marked the amount of vacumm on the meter. As the engine lost power slowly, I had time to reopen the fuel valve. This is how I determined and marked in the meter the amount of vacuum that tells me when I am close to time to change filters.
 
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To determine when was time to change filters, while cruising I closed the fuel valve between the tank and the Racor and observed as the vacuum meter needle indicated increasing vacuum. At some point, the engine began to quit and I marked the amount of vacumm on the meter. As the engine lost power slowly, I had time to reopen the fuel valve. This is how I determined and marked in the meter the amount of vacuum that tells me when I am close to time to change filters.

SeaMaster101 is wrong in my case. My T-handle gauges have three needles. One you set as a warning point that stays put. One that senses your vacuum and one that follows the vacuum needle and is left behind. At the end of a trip I can and do check the position of the needle left behind and an indication of maximum vacuum experienced.

My previous boat had gauges plumbed to the fly bridge.

My gauges read negative at rest so I don't believe the markings. I did clog and lose one engine underway soon after I bought the boat. The engine was quitting in the yellow zone. So I marked it. Never thought of shutting off the fuel flow and marking it that way. Great idea. Thank you.
 
I change no later than when maximum RPM can't be reached.
 
SeaMaster101 is wrong in my case. My T-handle gauges have three needles. One you set as a warning point that stays put. One that senses your vacuum and one that follows the vacuum needle and is left behind. At the end of a trip I can and do check the position of the needle left behind and an indication of maximum vacuum experienced.

My previous boat had gauges plumbed to the fly bridge.

My gauges read negative at rest so I don't believe the markings. I did clog and lose one engine underway soon after I bought the boat. The engine was quitting in the yellow zone. So I marked it. Never thought of shutting off the fuel flow and marking it that way. Great idea. Thank you.

I will never say the gauges never work. What I was trying to elude is that there are so many things one need to watch on a vessel. Humans are not very good cat that. How often you look at the gauges? If the answer is "every 5 min" then 5 min is enough time to seize your engine or fry something. In today days and age I rather let dedicated device monitor my systems and I enjoy boating rather well, and not behave like a watchdog constantly looking at the gauges and waiting for something to happen during the trip. Of course that is personal choice. I speak only of one Atlantic and one Pacific crossing. My approach has saved me well. I hope your does too...
 
Vacuum gauges do not need constant monitoring. Once a day would be a lot. In fact, the only time one would want to watch the gauges closely is after taking on a new load of fuel.
I will never say the gauges never work. What I was trying to elude is that there are so many things one need to watch on a vessel. Humans are not very good cat that. How often you look at the gauges? If the answer is "every 5 min" then 5 min is enough time to seize your engine or fry something. In today days and age I rather let dedicated device monitor my systems and I enjoy boating rather well, and not behave like a watchdog constantly looking at the gauges and waiting for something to happen during the trip. Of course that is personal choice. I speak only of one Atlantic and one Pacific crossing. My approach has saved me well. I hope your does too...
 
"The pressure gauges work just fine and show you when to change the filter. The issue with them is that you need to go see them when the engine is working and preferably working hard (above your normal cruising RPM) when the engine is turning around the most amount of fuel in order to asses the actual filter condition."

Seawater, true to a point. However, if you have a vacuum gauge with a drag pointer, you can determine the health of the filter at any time including when the engine is not running. Simple, effective and no need for expensive Bluetooth indicators.

Agreed, but so were paper charts: simple, effective and no need of expensive devices.... Don't tell me you still use these?
 
Not the same thing comparing electronic charts and monitoring the vacuum gauge on the Racor filters. I check the Racor drag occasionally, when I think about it, but when cruising we are using the electronic charts constantly.
 
I never thought of myself as being particularly fastidious on filters, but I am a bit surprised by the responses here. I've never waited until a filter was clogged to change it, and never waited until the vacuum was significant at the Racors. I usually change alternate ones yearly (on the dual Racor), a very small expense on a boat, and switch the selection lever. Maybe my tanks are extra clean or the fuel suppliers special. How many people are waiting until the engine dies or the vacuum gage is pegged before changing?
 
I like the n2k sensor. I can let signal k record the history and check and see the trend, not just today’s reading. Gonna have to order a couple of those up.
 
Not pegged and into the red. Change when needle goes into the yellow. Anytime before that is just plain waste. But, this is America. Do what you think is best for your boat and wallet. I am not a cheapskate but neither do I like throwing money away. Same reason I don't change my oil every 100 hours, a collosal waste.
I never thought of myself as being particularly fastidious on filters, but I am a bit surprised by the responses here. I've never waited until a filter was clogged to change it, and never waited until the vacuum was significant at the Racors. I usually change alternate ones yearly (on the dual Racor), a very small expense on a boat, and switch the selection lever. Maybe my tanks are extra clean or the fuel suppliers special. How many people are waiting until the engine dies or the vacuum gage is pegged before changing?
 
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