Improvised fuel polishing system

[Sven]

When we got the diesel "service" a week ago the mechanic advised us that we have an algae problem. He said there was mud in the primary filter and we should take care of it before any major excursions.

A built-in fuel polishing system is definitely on the to-do list, but I didn't want to tackle that right away. I don't want the list of projects to get out of hand.

As far as I know, there are no tank inspection ports or any other holes into the tank other that the fuel pick-up, air vent and the fuel filler hose. If anyone knows this to be wrong I'd love to hear where there might be other access holes in a tank on a 39B.

What I am considering doing as a stopgap is the following, and advice would be welcome:

1/ disconnect the fuel pickup before the first filter (shut off the fuel first)

2/ get an electric pump suitable for diesel and prolonged running (any suggestions for such a pump ?)

3/ plumb the pump temporarily to the fuel pick-up line

4/ plumb the outlet of the pump to a hose which is long enough to reach the fuel filler cap (any cautions for what kind of hose it should be ?)

5/ get one of WM's new Baja filters (the ones practical sailor said is even better than the original Baja filters)

6/ turn on the pump and let it cycle the diesel through the Baja filter, checking and clening it as needed

7/ add a biocide while running the cleaning process

8/ hope that a day of polishing gets rid of the worst stuff and that the biocide has killed off anything that remains in the tank

Any better ideas ? After reading Calder's diesel book I don't even want to add biocide until the fuel has been polished as I gather that could really gum up the works. I can't think of any way of stirring up the tank contents while running the cleaning. Would I be better off finding a mobile fuel polisher to do the job ?

Thanks,


-Sven

 

[MarkA]

Ditto

I have the same questions, and I'm eager to hear people's opinions.

 

[Tom Plummer]

Here is a drawing of how I plumbed mine in permantly.

 

[newgringo]

Sven,
Another boater I know got into trouble after some very rough water sailing. Apparently the junk got dislodged by the fuel sloshing around. He had had no problem for many years before. So my 2 bits is a built in polishing setup may help after you have a good clean system to start with. On our E32-3 with a very convenient 6 inch access port, cleaning the tank was easy with rags and a long arm. Putting in an access port may be worth while. Looking at my tank, which has a nice flat top surface, installing a port could be done with the tank in the boat. At least that is what I would try to do if it were my project. It always the unknowns that get us, isn't it?

 

[rwthomas1]

Here in RI there are fuel polishing services that are quite reasonable. They come to you with a mobile filter setup, tap into your fuel system and clean out the whole thing. They will get you completely cleaned out. RT

 

[Sven]

Hi Tom,

Here is a drawing of how I plumbed mine in permantly.

So it is wired to either recirculate (filter) and fill (bleed) regardless of the engine running, or to turn on whenever there is oil pressure ? Did you wire that to an existing oil pressure switch or did you add that extra switch too ?

I assume the check valve is there to reduce the need for bleeding after long periods of not running ? Is that standard ?

Where did you get the pump and do you remember what model it is ?

Did you hook it up to a single filter or did you rig parallel filters so you could switch easily ?

Is the valve V2 there to provide the bleed pressure ?

Would the standard lift pump (P1) pull fuel through the electric pump if it was not on ?

Did you wire the DPDT switch at the main circuit breaker or did you place the switch near the engine ?

Sorry for all the questions but I want to understand what I'll be getting into when we do the permanent installation.

Thanks !



-Sven

 

[Sven]

Rob,

Here in RI there are fuel polishing services that are quite reasonable. They come to you with a mobile filter setup, tap into your fuel system and clean out the whole thing. They will get you completely cleaned out. RT

In the short term that would be the easiest, by far, if they are affordable. I did find at least one mobile polisher in the general vicinity of the bay and guess we should give them a call.

Thanks,


-Sven

 

[Loren Beach]

Straining out the gnats

Regarding "fuel polishing" we have some experience with this in the NW. Here in Oregon our river sailing is placid enough that the problem of plugging filters presents itself during a rough Columbia Bar crossing for a trip north up the Washington coast -- and that whole trip can be rough for 48 hours, all by itself. I am sure that the Vikings in Puget Sound have their own stories of big slamming seas in any of their several straits.

The sludge in the bottom of the tank will sit there for years and then the hard sloshing will stir it up and repeatedly plug filters and kill the engine. Meanwhile the Skipper is crouched over the engine changing filter elements and trying to bleed out the system for a quick re-start while the boat is rolling beam to beam in 7 foot seas 7 seconds apart.
An excellent to revisit your most recent meal!

The solution would seem to be a "polishing" scheme that taps into the tank exit and draws out fuel and runs it thru whopper-size filters... This can work only if the sediment is mobile enough, at the dockside, to get it to flow thu the fuel hose.
And, any sediment that will cling to the tank bottom at rest will still be there, waiting for enough motion to break loose the clumps.

Now the professional polishers can indeed do a complete cleaning job IF they can get their pressure hose inside the tank to spray the whole interior with the nozzle blasting the crud loose with diesel under pressure. This can often be done thru the gauge sender opening in the top... but then usually not into the other half of the tank beyond the baffle.

The *only* good solution is to have a clean-out port installed in the top of the tank, one port for each separate section inside. That way all the inside sludge can be easily pumped/wiped up and out and shiny interior restored.

I know of Ericson owners (among many other brands of boat) that have done this. Down side is that the tank must usually be removed and taken to the shop... On a twenty-year-old boat that is often a good idea anyway to clean it up and do a new pressure test.

So, my main caveat about fuel polishing is just not to expect *all* interior sludge buildup to be gone after the fuel in the exit line is filtered and returned to the inside via the return fitting. This would only work well if... you do this regularly on an already-clean tank. i.e. as a preventative measure.

Opinions rendered weekly (weakly?), and well worth the payment rendered.

Loren

 

[e38 owner]

Fuel Polishing

We bought a system from defender and it works quite well. We bought the portable system (although they have both)
A few of us on the dock chipped into to buy one. Every spring a polishing we go.

http://www.defender.com/product.jsp?path=-1|311|302335|7364|939820&id=921468

Algae-x

 

[Tom Plummer]

Sevn,

Yes you are correct it is wired so that there are 3 switch positions.

Fill/recirculate Used to either fill/bleed the system or recirculate which filters the fuel.

Run Used as a boost pump for normal operations. The Yanmar OEM fuel lift pump only has a lift capability of 4 inches and needed help. The reason for this position is that it shuts down the pump if there is no oil pressure. Had a very bad experience once with my dad’s Chris Craft and an electric fuel pump and was taking no chances.

Off Note the Electric feed pump has a flow through capability.

In order to make the system work power to the switch is not routed through the ignition switch.

I replaced the OEM oil pressure switch with a single dual contact switch. It has both N/C and N/O contacts.

The check valve was OEM. When I replaced the old leaking tank I removed it from the system. Per Ericson the valve was there because they used the same tank/plumbing for the gas and the diesel variants and it was only necessary for the gas variant.

Valve V2 was originally there to provide for fuel polishing. With the engine off and V2 open and S1 in the run position fuel is circulated from the tank through the filters and back to the tank. When I do this I change the filters to 30 microns initially to boost the fuel flow then work my way back down. Later when my tank sprung a leak I used it to pump the tank dry.

The DPDT switch is located at the fuel filter station.

All of the parts were purchased at Harbor Marine in Everett, WA.

 

[Sven]

Yes you are correct it is wired so that there are 3 switch positions.

So there is also an "off" position.

I replaced the OEM oil pressure switch with a single dual contact switch. It has both N/C and N/O contacts.

Are running without an oil pressure gauge ?

Valve V2 was originally there to provide for fuel polishing. With the engine off and V2 open and S1 in the run position fuel is circulated from the tank through the filters and back to the tank.

It probably only runs through the first filter according to your diagram ? Do you need to close V2 when running or are you continually recirculating while running ?

Thanks for the great info,



-Sven

 

[rwthomas1]

It would be a simple thing to build your own on board fuel polishing setup. A Holley "blue" fuel pump, AFAIK, is diesel compatible and relatively cheap. Racor 900 series filters are commonly available in marine consignment shops. Some brass valves, fuel hose and you are on your way. I would set it up so that the system can be operated while under sail. That way the agitation would keep the debris in suspension so that the system would suck it up. Regular use should take care of any possible issues.

That said, when I cut my leaking original tank out of my E38 there was a dark discoloration at the bottom. No sediment to speak of and the discoloration was not a film, goo, or anything else. RT

 

[Sven]

It would be a simple thing to build your own on board fuel polishing setup. A Holley "blue" fuel pump, AFAIK, is diesel compatible and relatively cheap. Racor 900 series filters are commonly available in marine consignment shops. Some brass valves, fuel hose and you are on your way. I would set it up so that the system can be operated while under sail. That way the agitation would keep the debris in suspension so that the system would suck it up. Regular use should take care of any possible issues.

That was exactly my thought, probably mounted so the filters are visible without lifting the companion way stairs and engine cover out of the way first. I'm thinking the filters could be in a hinged teak enclosure behind the stairs, above the engine enclosure.

I was also talking to a powerboater friend back in Sweden who suggested that some power boaters use daytanks, never drawing fuel directly from what could be a very dirty agitated tank.


-Sven

 

[Ray Rhode]

Sven,

I read Passagemaker and these trawler guys are anal about fuel polishing. The June 2007 issue had a very detailed article on the subject. You might be able to get a copy on-line.

The two things I took from the article are:

first, if the tank has been in use you should clean it. Years of accumulatioin are hard to remove with a polishing system because you need to break the sludge loose first.

second, you need a big pump to move a lot of fuel. This stirs up the crud and moves it through the filter quickly.


Ray Rhode
S/V Journey
E35-III, 3189

 

[Loren Beach]

"Tanks for a New Idea!" Ya Sure Youbetcha...

I was also talking to a powerboater friend back in Sweden who suggested that some power boaters use daytanks, never drawing fuel directly from what could be a very dirty agitated tank.
-Sven

Hmmm... I wonder if this idea could also provide one with a really well-filtered outlet line for one's heater / furnace? Those devices like really clean diesel, as well. Maybe something like a 10 gallon day tank with a large capacity dual filter and electric pump set-up leading to it from the main storage tank.

Interesting idea.
Thanks,

Loren

 

[Tom Plummer]

Quote:
Originally Posted by Tom Plummer
Yes you are correct it is wired so that there are 3 switch positions.
So there is also an "off" position.

That is correct.
Quote:
I replaced the OEM oil pressure switch with a single dual contact switch. It has both N/C and N/O contacts.
Are running without an oil pressure gauge ?

That is correct I am running without a pressure gauge. The Yanmar 3GM30F instrument panel has no provision for a gauge.
Quote:
Valve V2 was originally there to provide for fuel polishing. With the engine off and V2 open and S1 in the run position fuel is circulated from the tank through the filters and back to the tank.
It probably only runs through the first filter according to your diagram ? Do you need to close V2 when running or are you continually recirculating while running ?

That is correct F2 is the OEM filter and it located between the OEM lift pump and the injection pump. The injection pump is the reason that the bypass line with V2 had to be installed as its design will not allow fuel to free flow through it.

I have never tried running the engine with V2 open and I would advise against it. There is no check valve on the inlet to the fuel tank for the return line and the fuel dumps back into the tank at the top of the tank. If for any reason the feed pump hiccups you would more than likely get air drawn into the engine supply line. On my Yanmar this would air bind the injection pump which would then subject me to the very time consuming and tedious process of manually bleeding the engine fuel system.

 

[Sven]

Is the valve V2 there to provide the bleed pressure ?

Would the standard lift pump (P1) pull fuel through the electric pump if it was not on ?

After having looked at the diagram (and others) I wonder if you wouldn't want V2 to be or have a check valve in series ?

To my eye it looks like IF you don't turn on your pump and happen to leave V2 open you would actually bypass the primary filter and suck from the fuel return line (path of lowest resistance).

Note: IANPE (I Am No Plumbing Engineer).


-Sven