Fuel polisher question?

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Djoub

Veteran Member
Joined
Apr 23, 2018
Messages
60
Location
USA
Vessel Name
Melody
Vessel Make
Mainship 350
New to marine Diesel engines and fuel polishing and have a question regarding how to operate. Lots of info on what they do but not any info on how to use them .

How do I know if the walbro electric pump is pumping? I do hear a click every 1-2 seconds.

I read never pull un-polished fuel from one tank and return clean fuel to another tank, fear of overflow. I have 2 totally independent tanks. One almost empty and the other less then 1/2. Don’t think it’s possible to overfill.

How long do I run it for? Couldn’t find any info on the pump. Vacuum gauge not moving with it on or off. No idea how long GCF element has been in.

Only had the boat for a few weeks and lots of new systems, confusion, and questions. But I love a challenge and this forum helps.

My thought was to run the low tank (~20 gal)) for a hour thru the polisher, then move the fuel from the 1/2 tank (~75 gal) thru and eventually balancing both tanks. Slight list currently. Then top off both tanks with fresh fuel. Thoughts?

Any help for a rookie is appreciated. This picture is with system shut down. Valves are positioned differently when operating.
 

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I would run it for an hour and check tank levels to get an Idea of flow rate. Your plumbing is a bit of a mess (no offense intended). Lots of excess joints and not terribly logical flow path. Btw, Teflon pipe tape is generally a no no in diesel plumbing.

Depending on flow rate and how close to the bottom of the tank the pickup tube is, polishing is usually measured in hours. If you traveling in sloppy conditions where the fuel is sloshing, running the poliser tends to catch more of the stuff that usually sits on the bottom of the tank.

Ted
 
I'm not an expert, but 1 hour? I have heard overnight or at least 4 hours. Don't know, never had my fuel polished. I would pump all the fuel to one tank. Take a look inside the empty tank. Clean if necessary with a vacuum. Then pump the fuel into the other tank, do the same thing. Look, clean. Then polish the fuel and let it go into one tank. Depending on how much fuel you go thru. I would only use 1 tank unless taking a trip.
Just my opinion, for what it's worth.
 
I’m doomed. I don’t polish my fuel and have not been convinced as to need using the polishing filter setups most rave about. Now I do have a good filtering system and buy from presumably reputable sources.

I am not alone in my thinking. But, it does no harm other than take one’s time from more relevant needs.
 
I’m doomed. I don’t polish my fuel and have not been convinced as to need using the polishing filter setups most rave about. Now I do have a good filtering system and buy from presumably reputable sources.

I am not alone in my thinking. But, it does no harm other than take one’s time from more relevant needs.

Some folks...probably most...don't have polishing capability and, frankly, don't need one. Others do.

Buying fuel of questionable quality in less developed areas? It's often full of water and rust and other crud. Have funky old tanks? Yup, plenty of them out there. Have long periods of time when the boat just sits? That invites water condensation and algal growth. Have a newer diesel in an older boat? The new ones really need the cleanest fuel possible.

It goes on and on like this. Again, the majority (I'm guessing) of diesel-powered boat owners don't polish the fuel. And lots do.

One reason, not to be quickly dismissed, is the peace of mind factor. If I'm far from home and/or far offshore, especially if reliant upon a single engine, the peace of mind of having squeaky-clean fuel and less burden upon the engine filters is priceless.

The boat I used to work on in the Galapagos Islands was a 50-foot trawler-style tourist yacht with a single CAT diesel. Our fuel was siphoned out of old rusty drums that were barged out from the mainland...it was horrible stuff. When would the filters pack up? Of course, when the seas were up and all the crap in the boat's tank was stirred up. We'd have to shut down, draw straws to see who would go down into "the hell" (engine space), and we'd wallow beam-to while swapping out filters. The fuel plumbing didn't include polishing capability nor did it include parallel filters that would have obviated the need to shut down while changing a filter. Either...preferably both...would have made all our lives a hell of a lot easier.
 
My builder said a fuel polishing system I requested was a waste. Nevertheless, the system's pump has been handy in transferring fuel among my several fuel tanks because of the flexibility of the fuel manifold..
 
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I'm not an expert, but 1 hour? I have heard overnight or at least 4 hours. Don't know, never had my fuel polished. I would pump all the fuel to one tank. Take a look inside the empty tank. Clean if necessary with a vacuum. Then pump the fuel into the other tank, do the same thing. Look, clean. Then polish the fuel and let it go into one tank. Depending on how much fuel you go thru. I would only use 1 tank unless taking a trip.
Just my opinion, for what it's worth.

Suck and return to the same tank for as long as you wish. Set it up and go to bed if you wish.

IF you are transferring between tanks, obviously I would not recommend leaving the station.
 
If you ad a fuel conditioner at fueling and you buy from sources that sell clean fuel, you probably don't need polishing. If your engine pumps much more fuel than it burns then you're polishing while running.
Each of my Detroits pump 35 gph, but only burns 4 gph, and returns 31 gph to the tank. So the fuel passes thru the filters many times. If you don't have a high circulation rate you can add an electric pump that draws thru the primary and returns to the tank.
A good fuel conditioner will slowly dissolve tank deposits and also make it easier for the filters to separate out any water. No water in the tank means no organisms, no acid, no tank buildup if the fuel is clean.

Next time you buy fuel, check the fuel pump for fuel filters. See if there's a date or the filter looks like it was changed in this century.
 
New to marine Diesel engines and fuel polishing and have a question regarding how to operate. Lots of info on what they do but not any info on how to use them .

How do I know if the walbro electric pump is pumping? I do hear a click every 1-2 seconds.



I have a Walbro that I use to fill the day tank for my diesel stove. When switched on, it pulses every second or so. When the tank is low, the sound of fuel dropping into the tank confirms that every pulse results in fuel movement. My tank is 2 gal, and that little pump fills it in under an hour. On a recent long weekend, with the diesel stove providing cabin heat, the 2 gal tank was near empty by the end of the second day, then filled once with the Wpump lasted the rest of the weekend.
 
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