Pictures of your twin filter installation please

[Nicholson58]

Originally Posted by Tillsbury

Ok, so now I have one wall of the engine room clear for putting my new pair of racor filters into the fuel system. Does anyone have any suggestions as to layouts, schematics, thoughts about electric priming pumps, that sort of thing? I would like to get the plan fixed in my head before starting work, so it ends up as neat an installation as possible.

Advice about mistakes made also welcome, and how you would ideally like it.

Primary objective is to have the ability to clean/change filters on the go, of course. Any other things I should be considering?

Dip tube #1 to the selector valve for the electric boost pump or bypass, dual Racor (PARKER) filters and selector valve, engine filter and boost pump. I added: Dip pipe #2 to a DC circulating pump, Franz 1 micron polishing filter, dual discharge of filtered oil to the inlet of the PARKER filters and the Racor of the generator. Excess filtered 1 micron oil returns to the tank by dip pipe #1. Circulating pump is 10X the rate of the main engine consumption. The polisher runs if an engine is running.

In this way, no engine ever sees anything but 1 micron filtered fuel. I have not changed a Racor in four years. The Franz is changed annually.

[sailah]

Originally Posted by skipgundlach

My apologies - but I wonder if you have the PNs for both the housing and filters?

Mine are T-handle where yours are bolts, it appears, mine are 30 and 10 micron, and mine have a petcock on the bottom in place of a bung, but otherwise alike; I frequently refer folks to the polisher and dual racor solution, but don't have the PNs to tell them what to buy...

Thanks.

L8R

Skip

The filter housings are Shelco FOSBN-786-316 which translates to 9 3/4" filter length and 3/4" NPT fittings and 316L stainless. T handles would be nice, although I only remove them 1/year. I have petcocks on the bottom as well I think although I need to check.

https://shelco.com/wp-content/upload...-FOSBN-FOC.pdf

The filters that I use are from McMaster: PN 9982t13

https://www.mcmaster.com/9982t13

I use (1) 10 micron and (1) 5 micron. Even polishing all season, which for me is 150 hours and with a 72 gph pump which I'll derate to 50 gph, that's 7500 gals. They don't even look used although I change them anyways, same with my Racor. That used to get dark after 1 season. Now it looks great after 1 season. I'm impressed with your 3000 hour change though lol



The filter housings are great, although severely overkill. I would use the 5" tall versions or use spin on diesel fuel cartridges. Also 3/4" NPT needs to be bushed way down for normal boat diesel fuel line size. I think I use 3/8" on my boat. But I paid $14 for them so whatever.

[kapnd]

Originally Posted by SailRedemption

We have Fleetguard filters on Redemption. We bought a double kit with better filtration than a Racor 500 would have done for cheaper. Purchased from Seaboard Marine (Sbmar) who sells the filter housings with gauge and sells the Fleetguard filters. The filters have two stages each. So we have filtration from 20 to 10 micron on the first filter then 10 to 5 micron on the second. No water gets passed, not even emulsified.


Link for filter housing kit:
https://www.sbmar.com/product/smx-do...iltration-kit/

Links for filters
https://www.sbmar.com/product/fleetg...ilter-w-drain/

https://www.sbmar.com/product/fleetg...ilter-w-drain/

I'll have to snap a picture of our setup when I get to the boat.

Also on sbmar.com is a section titled “Tony’s Tips” with tons of practical information written by a top notch mechanic who is willing to share.
After going through a lot of fuel problems, I bought the “double double” system and the squeeze bulb primer, and was finally able to get clean, water free fuel to the motor, in spite of badly contaminated tanks. (I finally cut ports in them and got the tanks clean!)
My takeaway from my experience is that the Racors are not really the best available product, just a long standing habit in the marine community, and that overkill in fuel filtration systems is worth every cent.

[skipgundlach]

Originally Posted by sailah

The filter housings are Shelco FOSBN-786-316 which translates to 9 3/4" filter length and 3/4" NPT fittings and 316L stainless. T handles would be nice, although I only remove them 1/year. I have petcocks on the bottom as well I think although I need to check.

https://shelco.com/wp-content/upload...-FOSBN-FOC.pdf

The filters that I use are from McMaster: PN 9982t13

https://www.mcmaster.com/9982t13

I use (1) 10 micron and (1) 5 micron. Even polishing all season, which for me is 150 hours and with a 72 gph pump which I'll derate to 50 gph, that's 7500 gals. They don't even look used although I change them anyways, same with my Racor. That used to get dark after 1 season. Now it looks great after 1 season. I'm impressed with your 3000 hour change though lol



The filter housings are great, although severely overkill. I would use the 5" tall versions or use spin on diesel fuel cartridges. Also 3/4" NPT needs to be bushed way down for normal boat diesel fuel line size. I think I use 3/8" on my boat. But I paid $14 for them so whatever.

Mine are the standard 3/8 for fuel; I'm sure there is a series of that model housing.

As inexpensive as the filters are (and I change by vacuum reading, not anything else), I'd say that a bigger one is better. I don't recall the price of the housings, but the entirety, including hose and backing plate, was $500, so your $14 could certainly stand reducers' cost

BTW, I use the petcock to lower the fuel level before I drop the canister beyond the point of allowing air in. I pour the effluvia into my waste oil bottle on the first and then use portions of the second to rinse the first. The remainder of the second filter housing gunge is easily swirled up to loosen anything sticking, and use the petcock to drain out the heavier junk. A swirl and pour like the first takes care of the remainder.

My refill of those is accomplished via the suction pump I have at the end of the line; when the canisters are full, it resumes pumping as intended, and there's no bubble.

To say we like it would be a gross understatement. We run it any time the aux is on, and in lumpy seas when sailing, the better to pick up anything sloshed loose - though I very much doubt any such situation exists, now, after 12 years of use - and what goes into the Racor is already filtered to the degree of the Racors - so they don't get a lot of work

[exMaggieDrum]

I just diagrammed my fuel system:

[ben2go]

Originally Posted by exMaggieDrum

I just diagrammed my fuel system:

Nice work. Looks like a sound plan.

[Beau.Vrolyk]

We often change filters while running using the RACOR 75500. One simply switches to the standby filter and the engine never misses a beat. You can change the clogged filter leisurely.

The reason for changing a filter as soon as it clogs is that the next filter may clog unexpectedly, thereby putting your boat in danger. We never wait around for the last filter to clog. That would be unseamanlike.

[a64pilot]

How do you bleed the air from the filter you changed with the engine running?

[ben2go]

Originally Posted by a64pilot

How do you bleed the air from the filter you changed with the engine running?

An inline 12-volt pump with a momentary switch or a primer bulb like an outboard uses.

[exMaggieDrum]

Originally Posted by Beau.Vrolyk

We often change filters while running using the RACOR 75500. One simply switches to the standby filter and the engine never misses a beat. You can change the clogged filter leisurely.

The reason for changing a filter as soon as it clogs is that the next filter may clog unexpectedly, thereby putting your boat in danger. We never wait around for the last filter to clog. That would be unseamanlike.

If there is air in the lines to the filter on standby, in the filter housing itself, or from the filter to the "tee" to the engine, a quick flip of the valves to the standby filter may not keep the engine running and may mean a complete re-bleed of everything. It may be OK but what I do is always keep the standby completely bled before I turn its valves off and put the one I currently want to run on.



At least make sure all the air is out of the filter housing of the standby at all times.

[a64pilot]

Originally Posted by ben2go

An inline 12-volt pump with a momentary switch or a primer bulb like an outboard uses.

Won’t work, because since the engine is running the other filter is connected to the fuel supply, the one you changed is not, not until or unless you switch over to it, then the air goes to the running engine of course.

Without making a system complex you have to have the engine off to bleed the system, so you can change a filter when the engine is running by having the other filter selected, but you can’t bleed it, and if you can’t bleed it, then it’s not available for use.

My 4JHE is a little unusual in that it self bleeds so I’d bet that as long as I didn’t drain any fuel from the bowl and just swapped out a filter I could get away with it, maybe but not all engines self bleed.

However if your engine starts to droop in RPM due to a clogging filter and for whatever reason you need to keep going for awhile and can’t switch to the other filter, maybe you don’t have one or whatever, if you turn on the boost pump that you use to bleed your filter, almost certainly now that you have 10 PSI or so pushing fuel through the filter and not just the engine driven pump sucking it through, you can drive on for awhile until it’s safe to drop anchor and deal with the filter.

I would not use a squeeze bulb myself as none that I am aware of are certified for below deck use, and I guess Diesel must over time soften them cause some have split open.

The boost pump isn’t enough pressure to tear the filter medium and push trash into the injection pump, so it’s safe to do.
Most fuel filter systems, cars for instance have the filter on the pressure side of the pump, boats are unusual in that they don’t.

[model 10]

[QUOTE=a64pilot
Most fuel filter systems, cars for instance have the filter on the pressure side of the pump, boats are unusual in that they don’t.[/QUOTE]


What? The airplane I'm working on, almost at this moment, has a fuel strainer before the pump.

[a64pilot]

Originally Posted by Ecos

What? The airplane I'm working on, almost at this moment, has a fuel strainer before the pump.

Automobiles outnumber airplanes thousands to one, and every fuel injected car I know of has the fuel pump in the tank, and a filter downstream, even most carbureted cars same way, many carburetors had filters in the carb, but off hand I can’t think of a car that sucks fuel through a filter.
But yes, airplanes have the strainer, not filter, but strainer at the lowest point and all I have worked on also were drainable for water.
Often there is a screen in the fuel tank on the fuel line too. However it’s very important to understand that these are Airframe parts, not part of the engine.
Most often the fuel system on an engine is the responsibility of the engine manufacturer, so an airframe manufacturer doesn’t mess with it, Certification becomes a real bear if you do as the engine is Certified under a separate TC. It could be done, but why would anyone bring that kind of pain down on themselves? I would assume even as a manufacturer you would have to seek an engine STC. So no engine mounted fuel filters after the pump. Unless the engine manufacturer put it there.
However oddly the exhaust system is the responsibility of the Airframe manufacturer, and on Pratt turbines we installed the Starter / generator and prop governor, and on a couple of prop governors we modified them removing the synchronizers as we were single engine.
I had to often supply a set of drawings to whoever overhauled the governors so that they didn’t have to reinstall the synchronizer as without the drawings they had to return the governors to build spec.
However can you imagine clogging a fuel filter in an airplane? That is why the ones that do have fuel filters also have bypasses in the filters.
Turbines are only ones I know of with actual filters.

So, airplanes are not boats, many similarities, but also due to regulations many differences.
I’ve not seen a fuel filter bypass on a boat, they just shut down

A large reason to push fuel through a filter is it’s not hard at all if necessary to develop a 20 PSI pressure differential, 20 PSI isn’t high pressure, but even if you could pull a pure, prefect vacuum, something that no fuel pump is going to even come close to, your stuck with a max pressure differential of less than 15 PSI.

Now that I think about it, at least gasoline powered boats aren’t allowed to have pressurized fuel lines inside of the boat, that makes fuel injected outboards interesting to say the least, on my Mercury Verado there was a tank on the back of the engine that was kept full with a low pressure fuel pump and a float switch to keep it full, then in this tank the HP electric fuel injection pump sat so that it could provide HP fuel for injection.
Apparently USCG regulations don’t allow a HP pump in the tank like on a car, reason is a pressurized fuel line can leak or spray fuel into the boat, where if under a vacuum it can only suck air.
So from a safety perspective having a leaking hose result in an air leak and engine shut down is safer than filling the bilge with fuel, especially gasoline.

[Tillsbury]

Originally Posted by jwoytek

The previous owner/builder of our boat installed a dual Racor filter system (photo attached--apologies for the low resolution). It has valving to allow for the filters to be changed individually. It is simple and does not involve a lot of fittings. I like the idea of the vacuum gauge that some here have mentioned. The way everything is situated in our boat, there is no separate lift pump to our Volvo Penta 2002. The fuel tank is immediately to the side and above the engine, so there's not a lot of line to prime and not a lot of friction to overcome.

That’s a lovely neat example of the simplest possible arrangement. Now I need to think about how I include a vacuum gauge, and fuel pump for priming ideally.

[Q Xopa]

Originally Posted by a64pilot

Won’t work, because since the engine is running the other filter is connected to the fuel supply, the one you changed is not, not until or unless you switch over to it, then the air goes to the running engine of course.

Without making a system complex you have to have the engine off to bleed the system, so you can change a filter when the engine is running by having the other filter selected, but you can’t bleed it, and if you can’t bleed it, then it’s not available for use.

My 4JHE is a little unusual in that it self bleeds so I’d bet that as long as I didn’t drain any fuel from the bowl and just swapped out a filter I could get away with it, maybe but not all engines self bleed.

However if your engine starts to droop in RPM due to a clogging filter and for whatever reason you need to keep going for awhile and can’t switch to the other filter, maybe you don’t have one or whatever, if you turn on the boost pump that you use to bleed your filter, almost certainly now that you have 10 PSI or so pushing fuel through the filter and not just the engine driven pump sucking it through, you can drive on for awhile until it’s safe to drop anchor and deal with the filter.

I would not use a squeeze bulb myself as none that I am aware of are certified for below deck use, and I guess Diesel must over time soften them cause some have split open.

The boost pump isn’t enough pressure to tear the filter medium and push trash into the injection pump, so it’s safe to do.
Most fuel filter systems, cars for instance have the filter on the pressure side of the pump, boats are unusual in that they don’t.

Yes agree mostly with what you are saying. Being a 'suction' system its normally not going to work.

I think with a header/ day tank setup it should work.

The head should be enough pos pressure to get air out of your filter housing with freshly replaced element.

There is obviously some 'ifs'' here. But assuming you have-
a day tank with some 'head',
Parallel filters, with
Bleed ports/ valve at, ideally at highest point on filter housing run, and
in and out ball vaves for each.

You should be able to-
Leave empty housing 'out' valve closed,
Open bleed port,
Open 'in' valve to the empty housing.
Wait for fuel to come out of filter housing bleed port.
Close bleed port.

If you have clear bowls you should see if filter housing is filling or emptying. So watching this as you open the 'in' valve.

As you correctly suggest with the engine sucking it may be the easiest path is for the air to be sucked into the filter through the open bleed port. This would depend on pressure 'head' from your day tank compared to suction force from engine pump.

If this was an issue, a, or a couple of check valves to stop the flow going backwards through the filters should fix it. As you say there is possibly some extra complexity.

I know a lot of the commercial guys, fishing boats etc do change filters on the go.