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2015-08-10

These fuelish things, revisited


While as functional as any daytank/gravity tank, this is too gruesome to endure.
The temporary, if functional "bungee-corded jerrycan half full of diesel" situation being about as far from code as I can bear, work has progressesg on the (at last!) installation of my FilterBOSS fuel cleaning device, and of the decision to either have the 100 gallons of diesel in my keel tanks polished on board, cleaned by a commercial service at the side of the sea wall, or simply disposed of as the cost of keeping my tanks less rusty in the last several years.

The Baja filter is the first step to clean fuel: Capture the bugs, grit and rust flakes before the diesel even enters the hose fill.

It's been some time, more than I would have preferred, since I last thought about diesel. But all things must pass, and when it comes to diesel, passing through a filter is a good idea. Some folk consider pre-filter assemblies an expensive complication, relying instead on physical scrubbing of their tanks and meticulous filtering (usually at the deck fill point via a Baja-type filter funnel) of any fuel they bring aboard. But as Colin Speedie of the long-legged yacht Pelerin acknowledges "if the fuel is dirty, once it’s in the tank, there’s not much you can do except dump it or keep changing the filters – that is, if you find out about it before the engine quits on you." "Dirty" in this sense could include either corrosion or debris from the tank itself, or from growth in the otherwise clean fuel itself.

The original pre-motor fuel filter was a tad basic.
I purchased the KTI Filter Boss unit some time ago at a bargain price. While I now have the skill set to (probably) build one at a cheaper price, I didn't back then, and besides, the Canadian dollar was over par, a situation no longer in effect. Like a lot of boat gear now being installed, it was bought out of sync with the actual progress of the project. Nonetheless, the first job was to mount it in a proper place.

On the aft bulkhead of the engine bay means a long, if shallow, run.
The fairly comprehensive literature from the makers of the filter unit specify that it should be kept as low as possible. With keel tanks, this is a challenge, and it may be necessary to put in, as is seen in Pelerin's installation, a "helper" inline fuel pump for when the lower parts of the keel tanks are being drained. Such a pump is the Walbro FRA-1 Industrial Fuel Pump, a robust little 12VDC diesel lifter.

The Walbro auxiliary fuel pump is on the right. The filter model is different from mine. Photo (c) Colin Speedie/S/V Pelerin
Because I had a spool of it, and because I have gone from a 52 to a 60 HP engine, I decided to change out the original 1/4" fuel supply and return hose to 5/16". This necessitated the purchase of a variety of hose barbs and T- and union fittings in brass for the various connections required. I also needed a whack of AWAB hose clamps, which are my preference when dealing with pretty well anything, but particularly anything that's involving fuel or is beneath the waterline. Being without perforations in their bands, they don't cause the hose material to bulge from the band, leading to wear.
It's ridiculous how many places I had to go to before I found "5/16 to 3/8 inch reducing hose barbs".

After the usual faffing around trying to divine from local chandlers whether they grasped my questions and debating whether I should just order stuff from the States, a local hardware store of vintage layout (Jacob's on Queen West, for the interested) had every brass bit I required, and understood my English, too! Each connection from tank to filters to engine was soon prepped with pipe dope and was carefully torqued.
I'm a dope addict, but only near my nuts.
The fractionally larger hoses required a fractionally larger hole through the forward engine bay bulkhead in order to reach the fuel tank manifold.
That's steel back there.

The big gun was summarily brought out.
I have four or five tradesman-grade Makita power tools. None have failed me. Black and Decker, on the other hand...

The fuel manifold was inspected and checked and (finally) labelled. It's under the steps to the saloon, which I took apart to better access the "taps".
Both taps to the right draws and returns fuel to the forward keel tank, both to the left, to and from the aft keel tank. Etc.
The fuel supply and return lines were secured to the starboard engine stringer, away from its heat and in a relatively sheltered spot.
Yes that area gets rubbishy and needs more janitorial service.

I have a large amount of wire loom aboard, but some of my wire and hose runs may be relocated for better securing once I've finished in here, and so I haven't yet installed in on every run as anti-chafe and related protection. So this setup isn't as anarchic as it looks.
The thick black hose is one of my hydraulic lines. The orange is a work light cord.

The Filter Boss is both easily accessible and visible from above, so filter switching on the fly is not difficult, and neither is reading the vacuum gauge on the front, which tells the skipper how hard the pump is working to overcome obstructions and/or cruddied-up filter to deliver fuel to the diesel.

Part of the "ignore the manual and wire separately" plot.
The manual suggested that power to the unit (which only requires a 5 amp inline fuse) be run through the diesel control panel key. Well, I didn't like this, not only for the longer run it would create, but because I had the main switch and my DC panel, complete with existing spare 5 amp circuit breakers, closer to hand. I also didn't want to have to switch on the key (and have it go BEEP, BEEP, BEEP!) in order to power the unit for "engine off fuel polishing mode". So I phoned KTI and got their blessing to do it via switches. Now, if you want to run the pump, you turn the main switch to "1", flick on the "MAIN" breaker on the DC panel, and flick on the "FUEL PUMP" breaker. Then if you flick the filter unit to "on", it gurgles happily. I also installed a warning light on the DC panel front that indicates when the pump is running and when the increasing vacuum suggests it's time to change filters. I intend to wire in an audible buzzer on that second circuit.


Mounted below the helm, but you get the idea.

This arrangement may seem overly complex. I don't find this hard to remember, but then I built it. I may have to come up with an operator's manual for others, however. I did for Valiente after I rebuilt and rewired the Atomic 4.

Looming disaster averted.
After checking for continuity, I didn't fancy the look of the four loose wires leading up into the DC nerve centre from the filter unit (two for DC power and two for the warning lights circuit), so I covered them in wire loom and secured them under the pilothouse decking.

Yes, forgot to open the bleed/return circuit, yes.
After purging the air from the lines into The Former Fuel Supply jerrycan (bubble, bubble, avoid some trouble), diesel was drawn from the tanks. It's elderly, but it looks no worse for wear. If I can burn what I have after going through the filters, I will be well-pleased.
Purge first, binge on old diesel later.
I will have to monitor the gauge for signs of "strain" and determine whether the extra complexity of the Walbro pump is required. I will also have to source bulk Racor 10 micron filter elements. I sense I may need them.
This is the finished product, running with fuel from the forward (No. 1) keel tank.

So far, so good. I ran the engine for about 15 minutes with varying degrees of RPM (in neutral gear, for the moment. Although I would like to put a three-way valve to allow the filter unit to bleed the system at a convenient point, and I have plans to put in a post-filter daytank so that I always have X litres of "known filtered fuel", that's this job done for now.

More bloody obscure hose barbs lie in my future, I think.

Next up: the mast. Oooh. To actually sail this season? It could happen yet.

UPDATE: 15.08.26:
If one looks three photos up, the rather dangerously high vacuum reading from the forward keel tank to the engine can be seen. I fudged this to test the system, but upon RTFM, I recalled that an "ideal" vacuum is more or less zero PSI and that the integral pump to the Filterboss is mainly there not to act as an auxiliary inline fuel pump, but is to power the engine-off, "polishing" function. Yes, if one's engine fuel pump packs it in, the Filterboss can do the trick in a pinch, but it's not meant to run continuously, as far as I can tell. So a call to "Andy at KTI" suggested, and, barring out too high of a height gap between the engine lift pump (hence "lift") and the Filterboss, it was probably crud in the pickup tube.
Somewhat improvisational approach to fuel line suction issue resolution.
In order to test this, I had to disconnect the fuel line from the pickup tube and run a temporary fuel source (in this case, a sacrificial cup) to the Filterboss and hence to the engine. Well, the needle pinning into the red zone went away with a quickness.
I murmured a Tarentinoesque "that's a bingo!" about here. Filterboss pump on...

This confirmed (as the fuel line end was only about the thickness of the fuel tank lid away from the top of the diesel within) that the pickup tube itself was likely cruddy.

...and Filterboss pump off. That's about zero PSI, meaning the lift pump is lifting as if the filters weren't there, i.e. "nornal operations".
So said pickup tube was removed and examined (for the first time!) and I got a strong sense of how deep the keel tanks are: some 31 inches.
Please ignore disassembled boat part chaos.
It's well-made, however, and looked rust-free, meaning there's little or no water in the tank. I sent a hose to the bottom and sucked out some fuel. Yes, there is some particulate matter there, but not nearly as much as I had feared.

Beware the lumpy goo!
A single chewing gum-like chunk of black goop was extracted, and I reamed out the tube with a wire length and generally cleaned up the threads. I replaced the thread tape (possibly the cause of the goop, it was far too gone to tell) and reassembled the pickup and fuel hose and bled the lines.
PTFE tape is to code for fuel-proximate threads.

While there was a slight increase in pressure, possibly because of the slight drop in fuel pickup level, the results were gratifying. I will do the second tank at my leisure, as the odds of burning 50 gallons of diesel before haulout are very slim, indeed.
Huzzah! Minus 1 PSI with the Filterboss pump off! WITHIN SPEC!
A couple of days ago, Ray Singh of Ray's Marine, the competent local tradesman, mechanic and technician who sold me this Filterboss unit an embarrassing number of seasons ago, pointed out that I should rig Ye Olde Jerrycan lashed down in the saloon one more time, because the sloshing of a proper sail will potentially loosen crud from the sides of the tank, overwhelming the filters and causes an engine shutdown or a pump failure. He suggested a sail followed by a more extensive pump out of the bottom of the tank(s) in order to see if there's more crud to remove, which in turn will dictate whether I polish what I have or replace it entirely.

But for now, I've fixed the problem of Excess Suck.