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Topic: Algae in fuel (Read 893 times) previous topic - next topic

Algae in fuel

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?
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Algae in fuel

Reply #1 –
You might consider getting a marine service to polish your entire fuel tank and then new filters.  Kieth Risch can also do this.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Algae in fuel

Reply #2 –
Quote from: Rudy –
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?
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Algae in fuel

Reply #3 –
No it does not.
Ken & Peggy
91 GV  U300 40'
DD 6v92
Build #3819
2023 Canyon Denali 4x4 crew cab

Re: Algae in fuel

Reply #4 –
The fuel in the tank is pumped out into a large tank.  It is triple filtered back into the tank.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Algae in fuel

Reply #5 –
Doesn't look like a horrible case.  BioBor treatment might solve it along with cleaning the pre filter a few times.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Algae in fuel

Reply #6 –
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.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Algae in fuel

Reply #7 –
Biobor JF at every fill especially if your going to be setting for awhile. Cheep insurance.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Algae in fuel

Reply #8 –
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
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Algae in fuel

Reply #9 –
Quote from: Pierce & Gaylie Stewart –
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?
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Algae in fuel

Reply #10 –
Quote from: dlkj07 –
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.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020
 

Re: Algae in fuel

Reply #11 –
Quote from: dlkj07 –
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?
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
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)