New Fuel polishing system - your advice needed...

[dansand]

Hello we are putting in a new fuel polishing system on our lagoon 500 and could use some expert advice on a couple aspects.

The two 120 gal tanks are about 25’ apart. We have run dedicated pickup lines to a racor 500 filter then to a small 12v Reverso 60gph pump then onto dedicated return ports on each tank.

We have installed three way valves so the system can work as a single tank polisher or a tank transfer solution. The pump and filter are about 4’ higher than the tanks.

My questions are:
- should we install antisiphon valves on the pickups or returns so the system doesn’t loose prime between runs?
- how have you solved the priming issues without the need for a separate fuel pump given the distance and lift issues I have?

I understand that this solution won’t be the silver bullet but it may help to remove crud on choppy days as the pickup is all the way to the bottom of the tank

Would appreciate any guidance or best practices you may have...

[Kenomac]

Here's a previous thread on the subject:

http://www.cruisersforum.com/forums/...on-132030.html

[1paulg]

I have a polishing system for each tank (500l) - the system pumps the fuel up to a holding tank located in the saloon where it either diverts back to the tank or supplies the motor(s) by gravity feed - the tank supplying the holding tank is easily switched . The system works really well as you should never get dirty fuel with it being continually filtered plus the fuel being supplied to the motors isn’t having to be pumped up 1.5 metres first

[Lepke]

The Reverso gear pumps I have used in the past are self priming to about 5' once the gears are wet. So if you've primed it or used it once, it should reprime itself.
The way I do fuel cleaning is to use the regular fuel lines, place the aux pump inline after the racors and vacuum gauge, but before the lift pumps and secondary filters. That way you have a backup emergency lift pump. With a small diesel, you add a pressure relief valve after the pump going to the return line. With bigger diesels with high flow rates, I just let it go thru the system.
I have Detroit mains that flow 70 gallons an hour when running. Both have an electric pump inline besides the normal lift pumps. If I run the electric pumps when the mains are stopped, the fuel flows thru both the primary and secondary filters and then back thru the return lines. Makes filling filters easier (you don't have to bleed DDs). But on the generators, it makes bleeding very easy.

[LongGone]

Originally Posted by Kenomac

Here's a previous thread on the subject:

http://www.cruisersforum.com/forums/...on-132030.html

Kenomac — just wondering if you have made any additional changes to your system since adding the separate Racor for the generator? Any observations on the effectiveness, performance, maintainability, reliability, etc.?

[blueazimuth]

Your statement that "... it may help to pick up crud on choppy days..." implies your tanks may not be spotlessly clean.
No fuel polishing system is going to be effective unless you start with absolutely spotlessly clean tanks.

Fuel polishing systems are just that - they polish the fuel but they will not clean a tank with crud on the bottom, and it is foolish to think that they will.

[GordMay]

Greetings and welcome aboard the CF, LongGone.

[Kenomac]

Originally Posted by LongGone

Kenomac — just wondering if you have made any additional changes to your system since adding the separate Racor for the generator? Any observations on the effectiveness, performance, maintainability, reliability, etc.?

Nope. Everything’s been working fine and as it should since I made the change. Having both the genset and engine on the same dual Racor was the source of the fuel starvation problem.

Now we just polish fuel on the day we purchase it, then polish once a week. The fuel filters actually stay very clean from the more frequent polishing, opposite to what you might think. The tanks remain spotless and free of growth.

[captainwireman]

Has anyone tried agitating and blasting the sides and bottom with a wand shooting compressed air? If you have the ability/room for this I would think it would be most effective but I thought I would see if anyone tried and had problems before I was going to try. New filters are on the way and I sure would like them loaded with slime before I changed them.
Another Question, will slime grow where the fuel doesn't reach as in a 1/4 full tank?