Fuel Polishing

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Properly engineered premium spin on filter which does the job £14.

Vs some pleated paper in a tin can, 1950's technology with bolts and rubber o ring seals, as much use as tow bar on a Reliant Robin. 1/10th as effective for £6.

I use these.....

www.ssldieselparts.co.uk/filter-filter-delphi-hdf496a-p-453.html
and
this is what is on my fuel line at the moment....

www.ebay.co.uk/itm/BOX-OF-10-FUEL-F...ols_Construction_Tools_ET&hash=item2ebc9b6a7d

Box of 10 = £5,71 each ??

Tom
 
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Cheers Tom,

I might give one of those a try when I've used up my two spare Fleetguards (after the one that's already in use).

I was rather hoping I have enough to finish the job now, although my tanks are rather dirty. 24 years of accumulated crud and no facility for draining the tanks means it needs a really good sorting.

Each tank to be done in two halves because of the baffle.

At last it feels like progress though:)
 

Tom,

Get real none of this stuff is any use as primary for your main engine and certainly no use whatsoever for fuel polishing.

Stop thinking about price and consider the job in hand.

These filters were made for little puddle jumper engines. Trundlebug has taken sound professional advice.

FS 1221 is probably equal to 10 of these tiddlers, so Trundlebug is saving £43 and doing the job properly
 
How do you know when to change the filter, out of interest?

When the flow stops going back to the tank.

I can hear the fuel dropping back into the tank from the breather hole, which helps. But also you can hear a slight change in the sound of the fuel pump.

I even noticed the pump note change when the filter was digesting some rather large chewy bits, although it soon settled down again if left to its own devices.

The idea of using clear hose on the inlet side was so I could see what was going on without the need for flow meters / switches etc.

KISS. "Keep it simple, stupid"
 
How do you know when to change the filter, out of interest?

The best way is with a vacuume gauge. I have one of these on the main engine filter, but have not bothered on the fuel polishing filter. If it clogs it won't damage anything other than, possibly the pump, which is cheap. A gauge would be useful, however, to worn of a bug problem developing. The polishing filter has much more fuel going through it than the main engine filter.
 
The best way is with a vacuume gauge. I have one of these on the main engine filter, but have not bothered on the fuel polishing filter. If it clogs it won't damage anything other than, possibly the pump, which is cheap. A gauge would be useful, however, to worn of a bug problem developing. The polishing filter has much more fuel going through it than the main engine filter.
OK.. but at 100lph, this is going to take quite some hours to clean a tank, so sitting there watching the pipes seems a little dull. Can you offer a link to the sort of gauge you mean, if you suggest using that as the "window" to the stae of play? Maybe its a sensible upgrade to this idea?
 
OK.. but at 100lph, this is going to take quite some hours to clean a tank, so sitting there watching the pipes seems a little dull. Can you offer a link to the sort of gauge you mean, if you suggest using that as the "window" to the stae of play? Maybe its a sensible upgrade to this idea?
Something like this
http://www.parker.com/literature/Racor/14396_Rev_-_RK11-1669_Gauge_Kit_Instructions.pdf
The gauge will fit on top of the Raycor turbine filters, it just screws in place of the T handle.

You can find cheaper non Raycor gauges if you hunt.

The gauge will only needed to checked occasionally.

For good fuel polishing the tank volume needs filtering many times. Even with my small polishing pump I put through the equivalent of the full fuel volume most weeks. I think the greatest benefit is when the tank is agitated so during and after a passage the polishing pump is left on for 12 hours, or more.
 
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Fuel polishing posts sometimes get confusing because there are two types of fuel polishing

1. Uses a high volume pump to stir up the tank contents together with a mobile pickup that is moved around to suck up debris from the tank floor and sides. This type of polishing is only done infrequently, usually when there is a problem, or once a year. The fuel is filtered over a few hours.

2. Perminant fuel polishing. This uses a smaller pump and a fixed pickup at the lowest point of the tank. It is used frequently, often daily. The volume of fuel filtered is much greater than 1, particarly over a year, but it filters all the fuel rather than targeting the dirtiest parts, which can only be done with a mobile pickup.it has the advantage that dirty fuel, or fuel with water in is is introduced it will be filtered immediately.

Both systems are effective, although if the tank is very dirty mechanical cleaning with rags etc may be needed
 
Something like this
http://www.parker.com/literature/Racor/14396_Rev_-_RK11-1669_Gauge_Kit_Instructions.pdf
The gauge will fit on top of the Raycor turbine filters, it just screws in place of the T handle.

You can find cheaper non Raycor gauges if you hunt.

The gauge will only needed to checked occasionally.

For good fuel polishing the tank volume needs filtering many times. Even with my small polishing pump I put through the equivalent of the full fuel volume most weeks. I think the greatest benefit is when the tank is agitated so during and after a passage the polishing pump is left on for 12 hours, or more.

As you know I am no Racor convert. As you rightly point out there are other sources, better and less expensive....http://www.designatedengineer.com/

In addition I have sourced restriction gauges from hydraulic hose suppliers, however you need to remember that most filter heads are tapped 1/8th NPT, not BSP.

Leaving a filter pump running vessel unnatended is recipie for flat batteries which is why I advocate using a timer or solar power, all simple stuff.

Once you get much more than 5 inches Hg restriction the flow delta at the filter begins to drop, double that and filter should be considered full.

Not sure why fuel polishing is considered normal on vessels in the US and why people make such a meal of it here. Picture is of a fuel transfer polishing set up with timer, now that is KISS
 
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Ok, but No2. is somewhat obsolete if you simply burn through the stuff using your normal filters? !

No the main engine filter will not do anything to clean the tank, the amount that is filtered and sent back via the return is small.
Diesel has some precipates and there is always some debris and water, so the tank gradually gets dirtier. Bio fuel and desel bug problems make this worse.if not cleaned the tank eventually becomes so dirty that it overwhelms the main engine filter. With a desel bug problem a new main filter can clog in minutes. These problems first show up at the worst possible time, when the boat is in rough sea conditions
Polishing the fuel cleans the tank and filters out water reducing the chance of a bug problem. Desel engines need clean fuel and some debris always gets past any filter. A clean tank and fuel will keep the engine healthier and reduce the risk of a nasty surprise when the going gets rough.
 
As you know I am no Racor convert. As you rightly point out there are other sources, better and less expensive....http://www.designatedengineer.com/

ye gads, my eyes are bleeding!

i think, from that site, i'd want something like the following:

# 601 BUILT IN BRACKET 3 1/2" PORTS
2 outlet 1 inlet $115.00
Filter Restriction Gauge with Drag Pointer
second pointer stays at highest reading $55.00

the seamax head with the nice drag pointer guage?
 
.if not cleaned the tank eventually becomes so dirty that it overwhelms the main engine filter.
Surely that should read "could"?

I quite like this idea, but if I put in half a tank and burn through it in two weeks, am I really going to be building up a soup? Cleaning 1 I can grasp; I am struggling with the need for cleaning 2.
Bouncing about at sea presumably stirs up the soup, and if your Racor paper filters are clean after 3000 litres, quite what are you achieving with cleaning 2?
An open question, that is all.
 
Surely that should read "could"?

I quite like this idea, but if I put in half a tank and burn through it in two weeks, am I really going to be building up a soup? Cleaning 1 I can grasp; I am struggling with the need for cleaning 2.
Bouncing about at sea presumably stirs up the soup, and if your Racor paper filters are clean after 3000 litres, quite what are you achieving with cleaning 2?
An open question, that is all.

Good point gigm, it would be interesting to learn how many boats actually have problems and how old the boats are and just how much if any diesel they have used in the two years preceding the problem.

I realize the 2 method picks up from the bottom of the tank and your engine pick up should be a few inches from the bottom but i have only ever had fuel problems once.............

boat was 15-17 years old.
Fuel gauge was bouncing between empty and reserve (I had about 19 gallons left in a 150 gallon tank)
and it was very rough ( 3 maydays in progress due to sea state)

I changed one prefilter and that was the end of the problem.
I didnt polish my tanks. I just filled them up and carried on to the channel Islands and Back to the Humber without further issue that year or subsequent years.
 
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Good point gigm, it would be interesting to learn how many boats actually have problems and how old the boats are and just how much if any diesel they have used in the two years preceding the problem.

I realize the 2 method picks up from the bottom of the tank and your engine pick up should be a few inches from the bottom but i have only ever had fuel problems once.............

boat was 15-17 years old.
Fuel gauge was bouncing between empty and reserve (RN&S yacht club fuel berth was closed)
and it was very rough ( 3 maydays in progress due to sea state)

I changed one prefilter and that was the end of the problem.
I didnt polish my tanks. I just filled them up and carried on to the channel Islands and Back to the Humber without further issue that year or subsequent years.

Pete,

Further to this post you just made, would appreciate some thoughts on my new thread (Sprint fuel related) Thanks.
 
Surely that should read "could"?

I quite like this idea, but if I put in half a tank and burn through it in two weeks, am I really going to be building up a soup? Cleaning 1 I can grasp; I am struggling with the need for cleaning 2.
Bouncing about at sea presumably stirs up the soup, and if your Racor paper filters are clean after 3000 litres, quite what are you achieving with cleaning 2?
An open question, that is all.

I think you have a fair point here.

The reason cars don't require frequent fuel filter changes is because the fuel doesn't hang around long enough to build up any bug. It only stays in there for probably a month at most, but in many instances a few days before being used and refilled.

So I think the same would apply in boats; frequent usage must be one of the healthiest preventive treatments you can apply, problems will only occur where the fuel in the tanks remains idle for long periods.

In my case the tanks hold 60 gal each. At normal burn rate of 5L/hr it would take 109 hours running to empty them completely. That's about a year's use for me. Even in our recent week long holiday we only did around 35 hours.

Of course if I had more leisure time I could turn it over more quickly...
 
Surely that should read "could"?
l.
IMHO its more a matter of when. The crud just continues to builds up in the bottom of the tank. The length of time will vary a lot depending on many factors, particuarly the quality of fuel. The fuel pickup is raised off the bottom so it's not untill it reaches this level, or the tank is stirred up that you will notice a problem.
Unfortunatly more builders are putting in tanks which are very difficult to clean and have no standard access to the bottom to drain off water.
 
IMHO its more a matter of when. The crud just continues to builds up in the bottom of the tank. The length of time will vary a lot depending on many factors, particuarly the quality of fuel. The fuel pickup is raised off the bottom so it's not untill it reaches this level, or the tank is stirred up that you will notice a problem.
Unfortunatly more builders are putting in tanks which are very difficult to clean and have no standard access to the bottom to drain off water.

I guess I am concluding-personally- that if you boat at sea in mixed sea conditions,and you check your filters and they are always clean then you are not going to gain much by polishing your fuel.
But I accept that if you are having a bug problem, or like Trundlebug,use little fuel over a long period, the set up might have more use.

My engines burn fuel faster than the suggested pump flow rate, so I will have burned all fuel before it polishes it all.
Not knocking the set-up.. just wondering what I personally would get out of it. I would also like to be able to check how much muck the process was picking up.. that doesnt seem immediately obvious to me unless you pull up a chair for most of the day. With the normal set up, I can unscrew and check the paper filters and drain off fuel/water from the bottom of the housing.
 
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