Hot swap fuel pre-filters

[keepondancin]

I have quick swapped a Racor filter. I keep an athletic water bottle with a locking top filled with diesel, and squirt fuel into the filter case after changing the element, filling to the top and quickly put the top back on. Works very well.

[Lepke]

Originally Posted by Compass790

Thanks for posting Lepke,
Interested in the dimensions of your filters so i can relate them to ours. Our fuel consumption is way different at less than maybe a 1/4 of a US gallon per hr but if you give me a dimension I can work out a probable lifetime.
Yanmar says to replace their drastically overpriced final filter at 100 hr intervals
So far our 5 micron filter has done over 300 hrs but it is a much larger spin on for 1/2 the cost of a Yanmar filter. I modified the fuel system to my liking & to cut Yanmar out of the equation. Seems to be fine so far but happy to learn more.
We spend a lot more time sailing than motoring but often we anchor 1/2 hr from dive spots so its not worth sailing that is why engine tips are good.
thanks if you can help

I have old (about 1973) Racor 900 housings feeding a manifold. Rated at 90 gl/hr with a 2 micron element. I have a vacuum gauge on my fuel manifold that reads 0 in/hg when element is new and about 7 at 500 hours. Everything runs thru the manifold and each engine has a secondary filter of about 10 microns. The engine mounted filters really never get dirty, but catch a little water the primary misses and serve as a backup to the Racor if an element should come apart. I also treat my diesel every fuel up with Archoil AR6200. I never have fuel problems.
I use Baldwin filters and buy them by the case here: BF Web Express :: Order Baldwin Filters online - Best Prices, Free Shipping
https://www.racorstore.com/racor/turbine-series.html
or on eBay search for "900 turbine fuel filter housing" for a Chinese copy - about $65.

[jhulmer]

I have dual tanks and made my own system to swap between them and prefilters. I like redundancy on mission critical systems. I used a 4 way (6 port) valve to handle the fuel returns but You could easily adapt this to a hot swap filter using the Moeller 3way valve. Valve feeds one or the other filter at a time and the output on the filters run to a "Y" then to the engine. I can't remember if the Racors have builtin check valves but an inline check valve would be required on the outputs. I change the filter and add fuel into the top of the filter before I close the top.




https://www.defender.com/product.jsp...263&id=2178741

[Q Xopa]

Originally Posted by a64pilot

You can change it, but you can’t bleed it.
Now if you don’t drain the bowl etc, then maybe your engine will “eat” what air there is, I think my old 4-JHE would as it’s a self bleeding engine, many are, not all are.
So as long as there is enough fuel to keep it running it will pass the air onto the return fuel line.

But I’ve yet to need to switch filters when running, what are the odds that you need to switch filters and change out the old one without shutting down?

Yes that is exactly my understanding too. But as you say some engines can tolerate a slug of air, and just have a little cough and keep on going ok. I agree on how big the air bubble is and how air bubble tolerent your particular engine is.

Also I agree that you may or may not be able to fill the bowl completely enough with diesel before putting the top back on with as was suggested a squirt water bottle/ syringe/ a cup/oiler can, or something else you come up with. Again this depends on access and what you have etc.

I have often done this sort of thing. Often successfully, often after some messing around. Sometimes you have to try other methods to get that air out.

Some times bleeding a diesel can be straight forward and quick, but others it can be a battle to find and remove that last bubble.

[Q Xopa]

Originally Posted by jhulmer

I have dual tanks and made my own system to swap between them and prefilters. I like redundancy on mission critical systems. I used a 4 way (6 port) valve to handle the fuel returns but You could easily adapt this to a hot swap filter using the Moeller 3way valve. Valve feeds one or the other filter at a time and the output on the filters run to a "Y" then to the engine. I can't remember if the Racors have builtin check valves but an inline check valve would be required on the outputs. I change the filter and add fuel into the top of the filter before I close the top.




https://www.defender.com/product.jsp...263&id=2178741

All true.

My preference is to use 2 x single valves and a T/Y instead of 1 x 3 way valve, to do the same thing.

Cheaper and much easier to find.

[sailingchiro]

Maybe I have been doing it all wrong but anytime my vacuum gauge creeps up, I open the Racor and change the filter with the engine running. I just have a jerry can available and fill the racor to the brim after changing the filter then screw cover on to top. Alittle spills out but have a diaper under to catch spillage. Have I been doing this all wrong?

[Q Xopa]

Originally Posted by sailingchiro

Maybe I have been doing it all wrong but anytime my vacuum gauge creeps up, I open the Racor and change the filter with the engine running. I just have a jerry can available and fill the racor to the brim after changing the filter then screw cover on to top. Alittle spills out but have a diaper under to catch spillage. Have I been doing this all wrong?

You are obviously doing your procedure fine, seeing it works.

Did someone say you are doing it wrong?

In my experience if you open a diesel fuel system and let air in, when it is running it will stop. I've found that unfortunately I cant get them to run on air, and I still have to keep buying diesel.

It sounds like, correct me if Im not understanding you correctly, that you dont let the filter bowl drain so the engine keeps pulling diesel. Im guessing, seeing you didnt elaborate, that you do this quickly enough before the engine drains the bowl. Is this what you are doing?

So thats obviously fine and it serves you well, great.

One other question, if I may, the remaining fuel in the bowl. Is it filtered or unfiltered fuel that has just caused your restriction and vacuum to go up?

Thank for sharing your exprience. Im happy to learn from you.

[a64pilot]

Originally Posted by sailingchiro

Maybe I have been doing it all wrong but anytime my vacuum gauge creeps up, I open the Racor and change the filter with the engine running. I just have a jerry can available and fill the racor to the brim after changing the filter then screw cover on to top. Alittle spills out but have a diaper under to catch spillage. Have I been doing this all wrong?

I would say yes, why do it with a running engine?
The vacuum gauge has a tattletale, there is no reason to look at it with the engine running, either look at it after you anchor, or before you pull anchor.
Fuel in the bowl is unfiltered fuel, its prior to the filter. Idea is of course that any particles are centrifuged out and any water being heavier will go to the bottom.
I believe the water part, but don’t believe most of us pull enough fuel for the centrifuge part.

The Racor 500 is good for 60 gallons an hour, now we all pump more than we burn, but as I burn about .75 an hour, it’s unlikely I’m even close to the fuel flow required to centrifuge the fuel.

[Madehn]

so i have the dual racor setup with the vacumn gauge- i really like it. I also have an electric fuel pump plumbed in that could be used if i have an engine pump failure or can be used to fill the filter bowls on the racors- works great as well. before i had this i had units i put together myself using valves similar to those pictured-- it was a fair amount of work to get a system set up that worked well and i had issues with air leaks -- my system had rubber fuel hoses attached to hose barbs in the valves etc-- overall the factory racor setup took up less room and was much more bulletproof- it was also expensive, you pays your money and you takes your choice

[Q Xopa]

Originally Posted by a64pilot

I would say yes, why do it with a running engine?
The vacuum gauge has a tattletale, there is no reason to look at it with the engine running, either look at it after you anchor, or before you pull anchor.
Fuel in the bowl is unfiltered fuel, its prior to the filter. Idea is of course that any particles are centrifuged out and any water being heavier will go to the bottom.
I believe the water part, but don’t believe most of us pull enough fuel for the centrifuge part.

The Racor 500 is good for 60 gallons an hour, now we all pump more than we burn, but as I burn about .75 an hour, it’s unlikely I’m even close to the fuel flow required to centrifuge the fuel.

Yes correct, the fuel in the bowl is unfiltered. That was what I was trying to hint at.

So IMO, if you do want to hot swap out the elements its best to drain the bowl of the potentially contaminated fuel, install new element then refill the bowl with fresh fuel until air is out.

With a good filter setup its unlikely to be ever needed.

However it could be nice to have if your having a bad day caught in a bumpy bit of weather, trying to motor from a lee shore, with sediment in your tank getting shaken up, and quickly clogging successive filters.

Another reason to have a onboard polishing and priming setup. A lot of people get away without this. Maybe its overcomplicated. I have installed this sort of system on my boat. Each to their own.

As I said if you can do this no probs if we can isolate the one getting changed and then fill it up completelty. With the right setup and procedure no big probs.

As someone has just said it can be done other ways like not draining the bowls etc. IMO there is a risk of letting dirty fuel into the dirty fussy bits like injector pump and injectors.

Yes agreed that with low fuel flows through a filter rated for much higher there isnt going to be optimum velocity to centrifuge water out efficiently. By the same token, the fuel is not getting as mixed so voilently so it can settle to the bottom of the bowl in a gentler fashion.

[a64pilot]

Assuming you have sediment that it takes a seaway to shake it loose, a polishing system isn’t going to get it, as the sediment is sitting on the bottom, until it’s knocked loose by sloshing fuel.
But if you use a boat frequently and turn the fuel often, then sediment isn’t going to be a problem.

Have you seen a tank professionally cleaned? They take what amounts to a pressure washer wand and spray the inside of the tank, because just pumping the fuel around in a circle doesn’t do much, and they have BIG pumps and BIG filters too.

Now if I had a common rail, then I’d polish to 1 micron, but for a different reason.

[NYSail]

I have the racor 500 as my primary with a 30 micron filter for my yanmar 4JH4E. What I love about the 500 series is that you can have the filter changed in a couple minutes tops.... been sailing for 20+ years (newbie) never had a clogged filter.

Good luck

[captnknopf]

I have a system I made that uses two filters per engine (I have two engines) and a pump that can be used to fill the filters and polish the fuel, sucking out of the tank, or even a jerry jug through the Racor in case the fuel is questionable. I have changed one filter while the engine is running. I used three way valves so it took two valves per system. My generator is also hooked into this system.

[Lepke]

In my boat and most boats I've been on have day tanks. The primary filters draw from the bottom of the tank and are mounted so the tops are lower than the typical fuel level. With dual filters, if you want to change an element running, the housing can be flooded by letting air escape at the top.
By drawing from the bottom of the day tank there is never a build up of sediment. If you filter the fuel coming from the bunker tanks, the day tank never gets a load of debris and you catch fuel problems long before the engine.

[HeinSdL]

I have a dual system (basically two Racor filters) which can be selected independently via some valves and a t-piece. There is also an electric fuel pump which can run by itself again via one of the two filters and condition the diesel in the tank via a magnetic filter which some say destroys bacteria. No idea if it's true but with all this talk of diesel bug I thought I'd put it in there. So when my boat sits waiting idle I can run the conditioning system and hopefully that keeps the tank clean. The tank does not have an inspection hatch so I have no idea what's in it and is hard to get to to install a hatch. So far though, no problems.

Having said all that - should one of the filters get plugged by this bug or whatever I can easily switch over to the other which should still be clean and get me home. I don't necessarily need to replace the plugged one while on the move but I like the back up I now have.