Diesel polishing- any body had it done????

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markspark7

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Just had my engine and heating system serviced has the engine would cut out at anything higher than tickover and the heating wouldn't start at all.Turns out the tanks have the dreaded diesel bug. The fuel filter even had its own fur coat...
I've been advised to have the tanks pupmed out and the fuel polished. Has anybody had this done and did it work??
The diesel is more of a brown colour than red so I'm wondering wether it's worth while just dumping the fuel and buying some fresh? There's approx 300-400 litres in each tank.
The fuel has been in the boat for some time has it came with the boat which had been moored up for around 18 months and even then I dont know how long its been in there.
Is there a live span for diesel where it reaches it's sell by date??

Regards
Mark
 
markspark7 said:
Just had my engine and heating system serviced has the engine would cut out at anything higher than tickover and the heating wouldn't start at all.Turns out the tanks have the dreaded diesel bug. The fuel filter even had its own fur coat...
I've been advised to have the tanks pupmed out and the fuel polished. Has anybody had this done and did it work??
The diesel is more of a brown colour than red so I'm wondering wether it's worth while just dumping the fuel and buying some fresh? There's approx 300-400 litres in each tank.
The fuel has been in the boat for some time has it came with the boat which had been moored up for around 18 months and even then I dont know how long its been in there.
Is there a live span for diesel where it reaches it's sell by date??

Regards
Mark
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I have a few friends who works with tank cleaning and such. They often keep the diesel that they work with and it contains a lot of shit :)
They put the diesel in tanks that that you can see thruu. The water and dirt seperates and they use the good part. Don´t know if it works the same when having bugs in the diesel
 
Firstly you need to treat the tanks with a shock dose of a good diesel Biocide such as Grotamar 82 and leave it do its work for three or four days to kill the bug.

You have water in your fuel if not the fuel bug would not have grown. From what you say it sounds fairly bad but without seeing it its hard to be definite. You need to clean out tanks and drain them of fuel bug and water, fuel lines and pick ups will need to be blown through backwards and fuel filters units dismantled and cleaned and new filter elements fitted. I would also keep three sets of spare elements on board fro the dead remnants that will come through with the fuel in the future.

If you have good access to the tanks with lids you can clean them out by hand if not filtering and returning to the tank is your only option, but you need to get out all fuel and water that you can.
 
Bandit said:
Firstly you need to treat the tanks with a shock dose of a good diesel Biocide such as Grotamar 82 and leave it do its work for three or four days to kill the bug.

You have water in your fuel if not the fuel bug would not have grown. From what you say it sounds fairly bad but without seeing it its hard to be definite. You need to clean out tanks and drain them of fuel bug and water, fuel lines and pick ups will need to be blown through backwards and fuel filters units dismantled and cleaned and new filter elements fitted. I would also keep three sets of spare elements on board fro the dead remnants that will come through with the fuel in the future.

If you have good access to the tanks with lids you can clean them out by hand if not filtering and returning to the tank is your only option, but you need to get out all fuel and water that you can.
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Would it be wise to throw the existing fuel them and replace it with fresh ?? what causes it to change colour??
 
I am in the process of fitting my own polishing system as it cost about the same to have it polished. At least this way i have the system installed for future use.

I bought it from a company called Hyphose in southampton, product is Racor so good reputation.
 
as had been said manytimes eradicating diesel bug is amatter of getting rid of your water bottom in tanl(s) and then treating with biocide. if you can find away to drain of pull out /suck out /drain the sediment so much the better.

A fuel polisher will only work if you can agitate the fuel in the tank sufficiently well to stir up any sediment, this entrained bug and fuel mix can then be passed to the filter so that it can do its job.

Any diesel fuel fliter could be used to polish the fuel, by recirculation, as a rule of thumb you need about 10 passes of the whole tank contents to achieve a polished state.
 
Mark, some people do it themselves and others employ a specialist company. As Bandit has said if a DIY job then you need Grotomar or an equivalent to kill the bugs before polishing.
 
markspark7 said:
Thanks.:encouragement: do you mind me asking how much you paid for it?
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Cant remember how much i paid for the polisher itself as i also bought a load of parts / pipe work etc, I had quotes for fual polishing of around £600 and know that its cost about that in bits, the only benefit is that when i replace the filters its only going to be a fraction of the cost next clean.
 
A simple and effective polishing rig can be put together for around £220. Ebay Fuel Separator filter - there is a Racor equivalent 500 series filter for about £80, a Holley 12 v fuel pump around £125.

Pump from one tank to the other several times, but pump the dregs from the tanks into 20 lt clear containers and use a flexi hose to get the clumps of bug waste out. The fuel in the clear tanks can be filtered again after it has settled.

Once the majority of the gunk is removed then a hefty dose of Fullest or Grotamar.

Then finally once it is clean a regular polish will keep it that way.
 
I had mine done about 2 years ago they polished about 600L for fuel and used a seperate tank /bowser to hold the fuel whilst polishing was in progress.
Then cut 3 access hatch into top of tank approx 125mm dia , started with 1 hole, but due to internal baffles had 2 cut additional holes.
This gave them access to clean the tank and remove the heavy **** that lays on the bottom of angle baffles plates.
I was surprised how hard the heavy slit and was and need scraping.

Once the tank was cleaned they removed the fuel pick up pipes and cleaned them, the one on the port engine was found that the end had been burred when it had been installed restricting the overal area available of the pick up.
The port engined always slightly lagged the starboard engine once over 3300RPM but reached 3700/3800 WOT but now it not lagging
They installed round plastic removal disk into the hole with mechanical fixing, which can be removed for future inspections, and do not leak.
Fuel was returned to tank, fuel filters changed and additives added.
They recommend fuel filters changed after 10hrs . During bleed off from the filters very small particle could be seen in the fuel.
Fuel was run down and after about 3 refuels the fuel was running clean no small particles primary filters where changed every 20hrs until clear .
 
Bazzer said:
Cant remember how much i paid for the polisher itself as i also bought a load of parts / pipe work etc, I had quotes for fual polishing of around £600 and know that its cost about that in bits, the only benefit is that when i replace the filters its only going to be a fraction of the cost next clean.
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I'm getting mine done for £95 a side ( 2 tanks) by a contracting company , not entirely sure what I'm going to get for that though..
My engineer is organising it all and he's sorting out a service , filters and additives etc..
 
markspark7 said:
I'm getting mine done for £95 a side ( 2 tanks) by a contracting company , not entirely sure what I'm going to get for that though..
My engineer is organising it all and he's sorting out a service , filters and additives etc..
Click to expand...

Wow thats very cheap, hyphose rent out the equipment alone for about £100 plus the filters per day, depending on how bad the fuel is depends on filter use.
 
We do this In Guernsey.

My advice is to treat the fuel with a shock dose of Grotamar 82 well in advance of filtering min 3 days, preferably a week before filtering, mix it with a half a gallon of diesel in a gallon can before adding it to your fuel to aid dissipation.

If you have inspection hatches all well and good, use them , most don't, cutting new hatches in the top of your tanks if you can get to them is another option.

Stripping out all water and crud wherever possible with the filtration unit or with a Pella type vacuum pump is also good.

keep several sets of spare pre filter elements for later use and always treat your diesel with a Biocide such as Grotamar 87, annually strip out water and crud from the bottom of your tank if you can ( I have sumps and stripping lines built in).
 
I've often wondered about a polishing system for Play d'eau but haven't done anything for the following two reasons,

1) In my mind I see a requisite of polishing as needing the tank contents to be thoroughly stirred up to lift the rubbish from the bottom of the tank to be removed by polishing. So the output from a polishing system needs to have a powerful jet pointing at the base of the tank to throw the muck up into the fuel as the suck side of the system pulls the dirty fuel out of the tank, filters it, and forces it out of the return jet to keep stirring the muck until there's nothing left in the tank but clean fuel. Doing this on a Fleming is hard to plumb since there are baffles which 'hide' areas of build up.

2) It's also very likely that the engine overspill of diesel as it passes through the primary and fine engine filters before being returned to the tank is in fact a polishing system in its own right.

Most of the issues in the UK are from diesel 'bug' which has multiplied, died, and fallen to the bottom of the tank forming a brown/black sludge. Without a powerful jet to scour the bottom of the tank, it'll be left there until such time that you are in rough seas with low fuel in the tank at which point the muck is stirred up ready to start clogging the filters.

The next issue as you say, is a growing water content in diesel. Thankfully in Guernsey we don't have bio-diesel so it's less of an issue than the UK and other areas. But again, the water separates and goes to the base of the tank, hence the continuing need to 'stir' the tank. Of course, having a poor O ring around the filler cap to allow water in, won't help!

Having said all this, there are powerful biocides available to us that not only kill 'bug' but are supposed to disperse water as well. Hence, most UK boaters simply dose fuel at every filling and end and start of the season.

So for Play d'eau, until a good plumbing system can be devised, we stick to biocide and hope....
 
Hi I just had a load of water enter both my tanks due to badly fitting fillers and a heavy sea. The Volvo agents tried to spin the fuel but after 4 hours and three or four filter cartridges they gave up and we dunpled the fuel. The water had gone through bulkhead filters and engine filters and affected the engines. Repair coat about £10k per engine, so the loss of 250 litres of fuel was no significant in the scheme of things.
Message : Make sure your filler cap seal properly. Put a ball of kleenex in the filler nozzle, put on the cap and run a hose over to 5 minutes - damp tissues + bad filler seals. DONT LEAVE ANY TISSUE BEHIND! Peter
 
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