Dual Racors. One or both when running?

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ksceviour

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This has probably been asked too many times to count however my forum search wasn't finding what I wanted so here goes.

Installing a set of Racor Max 75500's this week. How do most people operate with dual filters? Do they run with BOTH or a single filter using the other as backup. My initial inclination is to run on one filter to provide the 'contingency factor' of switching from a suddenly plugged filter to a known clean one. Personal preference or don't be an idiot everyone does it the same way? :nonono:

I'm not concerned about flow restricting my Perkins 6.3544 engine since its been running for several decades on a single Racor 500.
 
My initial inclination is to run on one filter to provide the 'contingency factor' of switching from a suddenly plugged filter to a known clean one.
The whole idea of having duel Racors is to run on one and switch to the other when needed, thus omitting having to change one in the ER when in a rolling sea.:blush:
 
One. I agree with below reply. :thumb:
 
This has probably been asked too many times to count however my forum search wasn't finding what I wanted so here goes.



You are correct, this does get asked and discussed a lot. That should tell you that it is a very good question to ask!

Your inclination is the correct one. Run one filter. Leaving the other as a "just-in-case" filter.

From that point, there are a lot of different ways to manage the filters. On my last boat I had a single Racor filter, now I have twins. I asked the same question you did and finally settled on what I will do as a maintenance schedule. Run on one filter, leaving the other as a reserve. After a year, I change the filter that was being used, and then run on the filter that was unused the prior year. I stick a piece of blue tape on the filter housing with the date it was changed written on it.

I have a vacuum gauge on the filters and have clean fuel. So replacing one filter yearly is overkill. However, the filters aren't that expensive and changing them is easy. I have also seen mixed information from Parker about whether their filter inserts age while sitting in the unused filter.
 
OK excellent. I'll stick to the plan then and I like the blue tape/ yearly switch over idea I'll be doing that.

My only remaining concern is you now have a filter canister with fuel sitting in it for a year although so does the tanks come to think of it. Proper use of fuel stabilizer to take care of that?
 
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My only remaining concern is you now have a filter canister with fuel sitting in it for a year although so does the tanks come to think of it. Proper use of fuel stabilizer to take care of that?


I have never even thought about the fuel sitting in the unused filter for year. I have no idea. My experience over this last year was that there didn't seem to be any issue. As long as the bowl look clear I wouldn't worry about it.

On my sailboat I used fuel stabilizer every time I added fuel to my 50 gallon tank. I happened each July, often only taking 30 gallons of fuel.

I have not used any fuel stabilizer in my current boat. I use more fuel now obviously so the fuel doesn't sit as long. Again I am fortunate to have good fuel quality in my area. However, that is a question that I have been thinking about recently. It may be a good idea for me to use a stabilizer, I just don't know.
 
RACOR - Dual Filters - use them properly

I agree with all above. You run on one.

the only reason to buy the more expensive Dual parallel filter set ups with the special set up of the isolation valveing is to be able to change plugged filters without turning off a single running diesel engine on your boat & leaving you dead in the water while you change a filter out at sea.

Been there & done that & it is not fun & can be messy.

Only time you would go to "both" valve position for more that a few seconds while changing over to the other clean filter when the first one is plugged up, would be if both were plugged up & you had just a very short distance to go & selected that to double the filter surface area to reduce the vacuum draw overload on your lift pump temporarily to squeak in to your slip rather than change the both that are now dirty & plugged up in both filters.

Other wise always run on one. Label the filter your running on with the easily removable painters blue tape with the date you replaced the filter last time to keep track.

I agree with Dhays that you once a year replace that one filter you ran in that year & then switch over to the other one. So no filter is ever over 2 years old.

The last thing you want to do is change a filter at sea in ruff weather while your dead in the water & rolling gunnel to gunnel when you have guest aboard.
Filters only plug at the worst possible time & plug up quickly when your in ruff weather as that is when all the boat movement stirs up the stuff on the bottom of your tanks, it becomes held in suspension in the fuel & gets caught in the filters.

So run on one & the other is your back up standing by for an almost instant ability to be put into action. Your all set for a summer of boating fun.

Have fun boating this summer.

Alfa Mike :)
 
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All these reasons are why I'm installing the dual Racors. We recently aquired this boat and one of the priorities was to upgrade the filter system. The last owners were marina dwellers but we aren't. We've avoided rough water until I can do this modification.
 
Great input everyone. Thanks a bunch.
 
If you ask engine mechanics you will get just as many one way as the other. I always run one at a time because I don't run that much fuel through and the design of the dual set up is to change one while the engine is running off the other one without spilling fuel or shutting down.
 
Run on one, you are nowhere close to max flow through the filter.
 
Concur with the above. We run on one only also. Did have to switch over to the other last year after 160 days of running on the first. Switching over while running was easy and allowed me the opportunity to replace the first while at anchor next day.
Oil filled vacuume gage is an upgrade that I highly recommend.
We have a label maker onboard and we change all labels when doing annual maintenance or as needed for unscheduled items.
I also installed a small dry erase board in the engine room to keep track of other things. My go to for quick reference.
Cheers
 
I run on one filter. I also change from one to the other every now and then..no set schedule. Occasionally I get yellow fuel in one canister and light orange in the other and it bothers me so I change to the other filter.

Also, for me-good to know it works, nothing mechanical likes to just sit there doing nothing.
 
OK excellent. I'll stick to the plan then and I like the blue tape/ yearly switch over idea I'll be doing that.

My only remaining concern is you now have a filter canister with fuel sitting in it for a year although so does the tanks come to think of it. Proper use of fuel stabilizer to take care of that?

It's been my experience that one or even 3 year old diesel fuel is not a problem as long as the system is clean.

Ken
 
If you are concerned about the fuel going stale, just switch over filters for one day about 6 months in then switch back.
 
It's a no-brainer. Run on one at a time.
 
I'd like to see images of the standard dual racor configuration/s. Mine has dual but the way they are plumbed seems overly complex which can lead to confusion. Also with mine, the outlet pipe from one is a smaller diameter than the other. Seems strange.

Ryan
 
Best-but-lacking photo I've got of my Racor filter plumbing. Equal hose size for input and output.

 
I wouldn't steal it, but I might copy it...
 
RACOR - Dual filter with single control - What i run

2666808.jpg
 
Here's an old photo of mine from a couple of years back when I first got the boat prior to having the fuel polished.

Note the outlet pipe from the port side filter is smaller in diameter than the starboard filter. Not why this would be the case as they both lead to the same manifold which feeds the engine and genset. Both filters are the same size.

Perhaps it's just my simple mind but the collection of valves seems to make the entire configuration quite complicated to work through when you want to make adjustments.

Apologies to the OP as maybe I should have started a new thread but the line of inquiry is very similar.

Hope I can figure out how to display an image.

Ryan
IMG_4257.jpg
 
It does seem odd to have the two different diameters in those outlets.
 
"All these reasons are why I'm installing the dual Racors. We recently aquired this boat and one of the priorities was to upgrade the filter system. The last owners were marina dwellers but we aren't."


For a real upgrade relocate the filters out of the engine room , so when one needs to be changes its safer , and easier.

When a filter plugs it is usually bad fuel, or a buildup of crap on the tank walls that is now loose.

Both of these hassles usually require multiple filter changes , underway if thats where you are.
 

I would like to correct one comment, dead in the water in rough seas, the Kadey Krogen engine room is the least rolly part of the whole boat.
I have sat down there for extended periods just to have a little break.
Well, that was also because I had no heat on the boat at the time, so it was the only warm place on the boat too.:dance:

Any pictures of me hugging that Lehman while underway are probably fake news.:lol:

Seriously, I did remove the flame shields:eek: at the bottom of each filter. I weighed the risk and I decided it was more important for me to see exactly what is on the bottom each time I do an ER check.
 
Seriously, I did remove the flame shields:eek: at the bottom of each filter. I weighed the risk and I decided it was more important for me to see exactly what is on the bottom each time I do an ER check.


That was probably a good call. While I hate those shields and wouldn't remove them, in your situation with your recent crossing, I think it was a smart idea.

That is another advantage to FF suggestion of moving them out of the ER. They woudln't need the flame shields.
 
Seriously, I did remove the flame shields:eek: at the bottom of each filter. I weighed the risk and I decided it was more important for me to see exactly what is on the bottom each time I do an ER check.

Same here. The racors are in a trough which is also the bilge. The heat shields made it harder to drain.
 
Flame shields - removal

I think I will join you guys now & also remove the flame shields :eek: at the bottom of each filter.

I Agree that it is probably more important to see exactly what is on the bottom each time I do an ER check.

I agree with the decision weighing the risk and deciding it was more important for me to see exactly what is on the bottom of the fuel filter each time I do an ER check.

The fire danger where I have located my Filters which is a away from the engine is pretty small plus with a Haylon system in the ER fire is less of an issue to worry about compared to fuel filters clogging up.

So glad to hear I am not alone with this decision.

Alfa Mike
 
If you have a fire severe enough to burn through the bowl with out the flame shield, your boat is already toast. Silly feature.
 

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