Fuel Tank Cleaning

[marjui13]

I live in Northwest Pennsylvania and believe our DP that we purchased in September of last year possibly had Algae in the tank after talking to several people. The rig is a 2008 with a Cummins Diesel and only had <13,000 miles when we bought it.

We have put more than 8,000 miles on it since Sept 2013 to January when we put it away for winter. We have experienced power loss intermittently which would either clear after we let it set or would change the filters. I am not a motor head but the problem does seem to be a plugging condition.

Since we have owned it we have had Freightliner in Gaffney completely service the coach which also included the Air Cleaner which wasn't bad but felt it worth the cost.

We took it out last weekend for a Shakedown cruise before a longer one to VA and the problem came back for awhile.

The codes indicate fuel rate is lower than it needs which also indicates a blockage.

I have kept the tank full and treated properly but others feel the algae was already there when we bought it due to sitting a lot.

I have been told I should have the fuel drained and filtered, tank properly cleaned of all sediment, algae, etc and the filtered fuel can then be pumped back into the tank.

Does this sound correct ?

Also does anyone know of a place that can perform this in my area of near Erie, PA

[wolfe10]

You are describing "Fuel Polishing". It is common procedure on pleasure boats-- they also have algae from their diesel fuel being stored. Check with a local marina.

Do you have one or two fuel filters? Are both being replaced if you have two?

What are you finding in the filters when you change them?

Are you using a Biocide such as BioborJF-- available at any marine store?

[BillAdams]

I would not go for a full fuel polishing until I have put the proper algaecide in the tank and run lots of gallons through the system. You might have to change one or both of the fuel filters once or twice (especially if you put some B10+ diesel in there) to get the system clean but if you want to find a quick answer (not necessarily a cure) to your current problem you can have the tank polished in hopes that this is the actual issue.

[marjui13]

I have 2 filters. As I understand it the one is the secondary filter with the Water sensor/drain. The other is the primary filter.

Both have been changed several times. I never thought about cutting them open to see inside.

I have been told that I should only need to change the primary when I suspect a plugging. The "Water in Fuel" has never come on.

As I stated since we bought the coach I have treated the fuel properly but the algae was probably already in the tank.

We have put 8,000+ miles on the unit between Sept and January of last year before parking for Winter.

Tank was filled for winter and treated.

Unit ran good for 200 miles last weekend before Power Loss came back.

[nitehawk]

Last fall, on the way to Texas, we couldn't get over 40 MPH. Limped into a city RV park. Turns out our primary filter was almost totally plugged with algae. Changed both filters, added an Algae eater called Starbrite diesel treatment from NAPA. About $18 for 8 ounce bottle that treats around 200 gallons. It seemed to do the job. I added another bottle about 250 gallons later and haven't had any problems. Was it changing the filters or the additive? Don't know, but all I do know is we haven't had any problems since.

Also, the tank fuel sender unit did not work before I added the additive. The additive must have cleaned the unit as now the dash gage is reading and moving when the fuel sloshes in the tank. I guess the POs parked our coach without filling the tank all the way and algae formed.

[wolfe10]

No, here is the filter order:

Fuel tank

Primary filter/water separator (10-30 micron filter element)

Lift pump/fuel pump

Secondary filter (2-5 micron filter element)

Injector pump/engine

And, when changing filters, both should be changed. Which one will be clogged depends on the particle size of the contaminants. With algae, it can be both as the can clump into slimy black mess that clogs the primary as well as individual bodies that clog the secondary.

You have said that the fuel was "treated properly". What algaecide did you use-- and in maintenance or kill dose?

[Walt2137]

No, here is the filter order:

Fuel tank

Primary filter/water separator (10-30 micron filter element)

Lift pump/fuel pump

Secondary filter (2-5 micron filter element)

Injector pump/engine

And, when changing filters, both should be changed. Which one will be clogged depends on the particle size of the contaminants. With algae, it can be both as the can clump into slimy black mess that clogs the primary as well as individual bodies that clog the secondary.

You have said that the fuel was "treated properly". What algaecide did you use-- and in maintenance or kill dose?

Yes Brett but on most Monaco coaches they installed the filters in the reverse order from what you posted so you have to be careful and trace out your fuel lines, I am going to change my setup one of these days after I use up all my spare filters.

[wolfe10]

Yes Brett but on most Monaco coaches they installed the filters in the reverse order from what you posted so you have to be careful and trace out your fuel lines, I am going to change my setup one of these days after I use up all my spare filters.

Walt,

Your post puzzled me, so I just called Monaco Technical (877-466-6226). Spoke with Jason.

I confirmed that the primary filter/water separator with 10-30 micron element IS first-- and he said was generally a Racor brand.

With the secondary/fine filter being after the lift pump. He did say that some of these engine manufacturer supplied secondary filters could also have drains.

[BillAdams]

I don't know about your coaches, but my coach uses what appear to be 2 identical metal encased fuel filters. However, you can't confuse them as the nipples they connect to are of different diameters. If one of your filters is a Racor you are also not going to confuse that with any other fuel filter so just put the right filters in the same place they are now and life is pretty simple. The filters are generally not hard to find if you look around a bit and once you find them all you will know where they go in the future.

[MadHungarian]

Just for general info, figured I'D contribute my $.02...

Fuel "polishing" very rarely cleans algae out of fuel - unless you have a very large and very tight micron filter assembly, somewhere in the 1-5 micron range, which is relatively unheard of in the automotive industry. The company I work for filters both diesel and jet at places like tank farms and airports in the millions-of-gallons range, and since these types of facilities turn fuel over at a very high rate, algae growth isn't much of an issue. We do, however, get algae growth and water/particulate contamination in some of our mobile equipment tanks from time to time due to inactivity. We usually either treat tanks with Biebor JF or, if the contamination is really bad, we drain the tanks and discard the waste fuel. We have recently begun equipping all of our equipment with drain valves and camlock fittings at the tank drains so that we can connect one of our small filtering units and a pump to the tank and circulate the fuel through a coalescer/particulate filter. This helps remove the moisture that promotes algae growth and also helps clean the tank surfaces inside the tank. We normally drain off the bottom of the tank, filter the fuel, then pump the fuel back into the fill port on the tank, effectively "rinsing" the tank and circulating the contamination particles towards the drain assembly so it can be filtered. This usually results in very clean fuel and tanks for about two years, depending on where one buys fuel and what the quality is.

As a word of advice, I'll say this, although many of you probably know this already: STAY AWAY from "Mom and Pop" stations when you buy fuel, if you can. Their tanks NEVER EVER get cleaned, and as a result they are usually moisture contaminated (along with mud, dirt, gravel, etc.) because their fuel doesn't get turned over as often.