I've had this coach around the 3-year mark I never had this issue until maybe the last 6 months or so. I'm getting what I believe to be black algae in my pre- filter.
When I initially saw this I purchased some biocide and introduced it to the tank but I've only driven it once since. So I'm hoping if I use the biocide as directed this algae will subside.
Any thoughts on if this is for sure algae or something else?
You might consider getting a marine service to polish your entire fuel tank and then new filters. Kieth Risch can also do this.
Does a polish involve removing the tank?
No it does not.
The fuel in the tank is pumped out into a large tank. It is triple filtered back into the tank.
Doesn't look like a horrible case. BioBor treatment might solve it along with cleaning the pre filter a few times.
No question. Whether or not you have the fuel polished (very common in marine diesel areas) or not, immediately put in a kill dose of Biobar JF and run engine and generator enough to circulate it.
And, correct, fuel polishing is with the tank in place.
Were it me, I would also, just start by buying 3-4 primary fuel filters. That may be enough filtration to clear it up. But (OK large BUT) be sure to check several times a day while driving because you don't want to starve the fuel injection system for fuel.
Biobor JF at every fill especially if your going to be setting for awhile. Cheep insurance.
I like just changing the primary filter with the clear bottom so any additional algae can be detected. Know how to do this on the road so you don't get stuck by the side of the road with air in the system. Keep at least two spare primary and secondary filters on board. I use our hand pump to push diesel through the new primary all the way to the secondary filter which I loosen a turn to get all the air bubbles out.
Polishing the fuel only transfers money from your wallet to the shops. A pristine clean tank is only good until the next fuel stop where more algae may be introduced. With an additive, any new algae can be killed before it multiplies and will find it's way to the filter.
Remember that your generator uses the same fuel (if diesel). I installed a larger filter with a clear bottom for the primary. While the electric fuel pump has a built in serviceable filter, I like catching anything before it gets to the pump. See my generator photos on older posts. Know how to service the electric fuel pump's small internal filter if it's the round type. Carry a spare also.
Never a bad idea to start the engine after fueling and watching the primary clear bottom for water and/or algae. Algae loves to grow in the interface between water and diesel, especially if it's warm. At least check it when you stop for the evening or in the morning before you head out.
Pierce
Thanks Pierce, Is the clear bottom to the primary filter a separate part or can I source the filter and the clear bottom as one piece?
Available either way. My suggestion is to have 2 of the clear bowls and gaskets. Put one on the new filter so filter change goes easier. Then remove and clean the clear bowl you are taking off and install it on the next filter to be used.
Dylan,
There are many primary filter styles with quite a few having a "sight glass" either incorporated into the primary filter or a clear plastic base at the bottom. In the attached photos, the Racor S3202 is threaded for the plastic sight/drain in the next photo. You just have to search for the combination you are happy with and will fit into that location.
In the last photo, the generator is shown with the additional fuel filter. This is the one I tapped for pipe fittings. I also used one of the ports for the new diesel heater directly above and under the sofa. The clamps are not "Euro" style but do wrap all the way around.
Anytime you have a gasket, it's an opportunity for air to leak in after time has degraded the gasket so good to check for leaks. I installed a filter with the same kind of glass at the bottom for our generator but didn't like the metric fittings with "O" rings as they failed my MityVac test so I tapped all the ports to pipe thread and now it's leak proof. Good to use Euro style hose clamps as the Autozone generic clamps my not clamp the hose all the way around and may be a point where air is introduced.
Good point Brett. The see through bottom in the photo is my extra one as well as the filters.
Pierce