Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: TheBrays on February 09, 2012, 09:50:01 am

Title: Fuel Polishing (was loss of power)
Post by: TheBrays on February 09, 2012, 09:50:01 am
Thread started because of references to fuel polishing in marine environments.
(I'll get to the topic soon)

Algae grows in diesel in the interfaces between the fuel and water. A good inhibitor can minimize this but you can still have some growth. You can 'shock' the tank by adding a lot (probably double the maintenance dose) but you wind up with more dead algae. Over time hard little 'asphaltines' can also accumulate in the tank.

The problem is acerbated by long idle times (no fuel flowing through the system) and condensation due to temperature changes.

Yes, you can find folks with fuel polishing rigs around areas with a healthly boat population.
The marine problem is that the fuel tanks are usually bigger and many boats often tend to not go anywhere.
Or, they putt out of the harbor, raise the sails, and off they go. They may not burn 15 gallons a season.

I had a 550 gallon fuel tank and put ~10,000 miles (at 9 mph) on my boat over 7 years-but that is a different story.

My mechanic buddy built a fuel polishing system we used every spring for probably much less than the service call to the professionals.

Consider:
  1) My (your) tank on the coach is ~150 gallons.
  2) I can run a hose from the fuel tank filler to a filter equipped pump and then run the output back into the tank.
  3) At a relatively slow rate of 10 gal/min The pump can 'turn-over' the entire tank in 15 min.
  4) Pumping directly back into the tank will help turn up the sediment at the bottom.

An example pump - Diesel Transfer Pump - 12 Volt (http://www.harborfreight.com/12-volt-diesel-transfer-pump-66784.html)
(~$130)
This has a 30 min duty cycle but you can run it, stop, go get a few more beers, repeat...

An example of filters to complete the  rig - Amazon.com: Goldenrod Standard Fuel Filter & Cap - 3/4in. Fittings, Model# (http://www.amazon.com/Goldenrod-Standard-Fuel-Filter-Cap/dp/B0000AXE6B)
(two @ ~$30    filters - $10-12 each)

Misc fittings and hose ?


We had two filter sets, one before the pump with either a wire mesh strainer to catch big stuff or a water block filter and one after the pump for fuel.

If the fuel is in bad shape have a good inventory of filters. When I first got the boat we went through 8 filters.

You probably need to enjoy the smell of diesel to go this route but...

HTH

elliott bray


Title: Re: Fuel Polishing (was loss of power)
Post by: wa_desert_rat on February 09, 2012, 01:20:13 pm
Great post! Thanks. I think I'll explore this idea although I did buy my RV from a family that had used it extensively for short runs to and from the mountains in the Puget Sound area. But since it's a 1993 it can't be a bad idea.

I would suggest that a WalMart kiddie wading pool (blue plastic) might be a good addition to catch any fuel that spills out of the filtration system. Would probably make the neighbors feel better about the operation.

Craig
Title: Re: Fuel Polishing (was loss of power)
Post by: Pierce & Gaylie Stewart on February 09, 2012, 04:11:37 pm
I had a lot of algae experience in both cars and boat. Nasty stuff once it gets growing in your fuel tank. With Foretravels, we don't have to worry as much as the fuel tank (at least on mine) does not have an open vent to the atmosphere. When you fuel, there are a couple of pounds pressure on the fuel cap when you remove it. With this arrangement, it's more difficult to bring moisture laden air into the tank. With my Detroit Diesel, over 100 gallons of fuel per hour is circulated with most of the fuel is returned to the tank. With a full fuel, the tank is very warm to the touch and with a half tank, it's too hot to hold my hand on it. Probably too hot to grow any algae. With a strong flash light and a small mirror, you can view the inside and bottom of the tank if the fuel is low. The primary and secondary filters should catch any algae that might be introduced from an above ground fuel tank. Good to have a couple of spares on board just in case. Algae is black nasty stuff, easy to see in the bottom of the tank or in the colored plastic screw on drain assembly at the bottom of the primary filter. Any water in the fuel tank will quickly find it's way to the plastic bowl and can be drained. Good to check if fueling from an station that uses above ground tanks.

Filter installation is straight forward. I leave the filters a couple of turns from being tight and then use the hand pump to fill the filters and get all the air out. Once the air is out, I hand tighten. Need something to catch the excess fuel so it does not go on the ground. Filling the filters before trying to start is very important on Cummins, CATs. No big deal with a Detroit.

Order the filters online, not at NAPA. Will be less than half the price.

Do NOT install a 2 micron filter as a primary filter for normal use. The 10 to 30 micron filter is what the factory recommends. As soon as fuel starts circulating, the 10-30 micron primary filter becomes more and more efficient as the miles go by. For a DD 6V-92TA, the Racor S3202 is the primary and is a 30 micron filter. The Cummins secondary filter available at truck stops is a 2 micron filter and although it looks the same, it should only be used in an emergency on a Detroit as the primary filter.

Pierce
Title: Re: Fuel Polishing (was loss of power)
Post by: Dave M (RIP) on February 09, 2012, 04:55:19 pm
We provide the "Fuel Polishing" service for a few of our customers (Generators) who have large storage tanks and not filled very often, so we put a 1" hose to bottom of tank (Pickup) and a 1" hose return to other end top, let the 3/4 hp pump  w/2 large filters clean (Polish) Love that word.  Let run for 24-36 hours, they are happy and so am I.  ;D

Dave M
Title: Re: Fuel Polishing (was loss of power)
Post by: wolfe10 on February 09, 2012, 06:35:50 pm
Yup,  very familiar with Fuel Polishing from years around the marine industry.  Fuel polishing by sucking high volume off the bottom of the tank and returning fuel to the fuel inlet DOES work.  And at least those in the Gulf coast area charge for the service PLUS how many filters they go through to move all the gunk from your tank.  They have restriction gauges on their filters so they know when to change them.

Brett
Title: Re: Fuel Polishing (was loss of power)
Post by: Merle Hench on February 10, 2012, 06:30:33 am
Excellent info. I was unfamiliar with this process. Thank you for sharing.

Steve
Title: Re: Fuel Polishing (was loss of power)
Post by: Greg and Viv on February 12, 2012, 08:53:37 pm
I just had algae in my fuel tank, clogged up the filter nothing but problems. Replaced the fuel filter and finally found Lucas Oil, Biomedic, additive, that breaks down the algae. Hope  it works.
Title: Re: Fuel Polishing (was loss of power)
Post by: Dave M (RIP) on February 12, 2012, 09:47:02 pm
Jimmy, Hope you carry a few spare fuel filters along, you surely will need them, you will know when the power starts going down, just find a nice place to change filters. Once the Alge starts, it will take a while to remove it from your tank/system, most likely will never remove all of it, it will show up every time you park for a while,  Why I suggest carry extra fuel filters, you will need em.
God luck
Dave M
Title: Re: Fuel Polishing (was loss of power)
Post by: wolfe10 on February 12, 2012, 09:52:45 pm
And, to minimize algae growth, when storing your coach:

Fill the tank all the way-- less condensation. Algae needs water to grow.

Add a BIOCIDE if storing over two months in the summer or 3 months in the winter.

And, I have not heard of anything that will eliminate/break down the algae in the system.  Kill it and prevent future growth-- yes, that is what Biocides do.

Brett
Title: Re: Fuel Polishing (was loss of power)
Post by: Jim Frerichs on February 12, 2012, 09:59:49 pm
Hi Brett,

Any brands you like?

Thanks,

Quote

And, to minimize algae growth, when storing your coach:

Fill the tank all the way-- less condensation. Algae needs water to grow.

Add a BIOCIDE if storing over two months in the summer or 3 months in the winter.

And, I have not heard of anything that will eliminate/break down the algae in the system. Kill it and prevent future growth-- yes, that is what Biocides do.

Brett
Title: Re: Fuel Polishing (was loss of power)
Post by: wolfe10 on February 12, 2012, 10:16:56 pm
Jim

I use Biobor-- mostly because they carry it at the West Marine store down the street from our home:

BIOBOR Biobor Jf 16 oz. Microbicide at West Marine (http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=21835&catalogId=10001&langId=-1&storeId=11151&storeNum=50366&subdeptNum=50396&classNum=50399)

Nothing special about them-- they are just a variant of weed killer.

One bottle will last you years of storing fuel.

Brett
Title: Re: Fuel Polishing (was loss of power)
Post by: Carol Savournin on February 13, 2012, 12:03:28 am

And, I have not heard of anything that will eliminate/break down the algae in the system.  Kill it and prevent future growth-- yes, that is what Biocides do.

Brett

We heard the same thing ... I think from some of the mechanics at MOT ... that the LucasOil product will break down the algae enough that you can eliminate it.  That might be hopeful fiction ... carrying extra filters is a much better idea.  We are not the folks who are going to be changing them ourselves ... but the mechanic we call to rescue us will never be without the proper filter for the job!
Title: Re: Fuel Polishing (was loss of power)
Post by: bbeane on February 13, 2012, 07:05:49 am
I keep mine treated with biocide (Raycor from local diesel shop) at every fill. I have a bigger problem keeping the fuel tank full it burns it faster than I can buy it. Around the house here fuel is creaping up on $4.00 a gallon again, brings a tear to the eye and big empty place in the wallet.
Title: Re: Fuel Polishing (was loss of power)
Post by: Greg and Viv on February 13, 2012, 11:19:58 pm
$4.00 per gallon, here in Ca. its around $4.25 on a good day!