Fuel tanks again

[Despacio]

Guess my old photos aren't viewable anymore. I had a request to repost them, so here they are.

Wood patterns made from Luan plywood, 1 x 1 pine, and sheet metal screws. New tanks are about 50 gallons each and are manifolded together on each side. They fit through the space at the front of the engine, and will come out if necessary.

Put in sight gauges with a valve at the bottom, and a small "T" (third photo) where I connected the two sides together with a small pump and a Racor filter. I can pump my fuel around side to side. Moving it keeps it from separating into sludge.

Cut the old tanks out in about 3 hours of hard labor. Total cost was about $3000.

I'm happy with how it all turned out, but if I were doing this again I might use pre made plastic tanks and put them on a welded aluminum frame. It would be far easier, cheaper, and in some ways, better.

[jleonard]

So you have 4 50 gallon tanks ? I think that is easily enough fuel capacity. Looks good.

[cct]

Thanks for the pics. Visuals are always worth 1000 words. I'm going to cut mine out over Thanksgiving break (leaks into the bilge weren't going over very well with the local authorities this summer).

Here's my plan. Feel free to add your inputs. I'll take all the suggestions I can get.
- Note: Our normal cruises are under 100nm round trip (Lake Ontario)

- I'm leaning towards building a wooden shelf then installing a bank of pre-fab 23 gallon Moeller poly tanks
- Part #: 032623 (23 Gallon Permanent Boat Fuel Tank, 24"L X 20"W X 12"H - Moeller)
- Initially I would install 2 tanks (1 on each side) on a rack large enough to hold 4 tanks per side
- Several benefits to this:
- I can keep the day tanks full (reducing condensation) and isolate the tanks I have no need for at that time
- I can better maintain a fresh fuel supply
- I can minimize gunk buildup because the same fuel will never be in there more than one season
- If a tank does gunk up, I can drain it then remove it and deal with in on land
- It opens up the engine room for more available working space

- The down side:
- These tanks are very limited on the ports / fittings
- The fuel distribution manifold would require a pump to move the fuel from one tank to the other since there are no ports on the bottom of these tanks

- The key is in the fuel distribution manifold. Any takers on how it should look?

[psneeld]

I just did 2 -58 gal Moeller tanks and plumbed the 2 tanks through the 2 Racor 500s I had on hand (previously one for my single engine, one for genset). The return manifold is above the main and based on the amount of returned fuel from both engines being so small is returned to the nipples on the outboard ends of the main manifold pointed up.

The center nipple on the lower manifold is just a tap for clean fuel.

[Despacio]

I think you have a good plan, those tanks look perfect.

The fuel gauge shown in the photo probably isn't necessary as you might be able to see the fuel in the tank, those gauges are not very reliable, and I have had one leak at the screw holes.

I like running the engine off of one tank, designated as a day tank, then pumping it from the others into that tank. If you do this you don't need a fuel distribution manifold.

The day tank has the pick up for the engine, and the fill where you can "T" for the return (if one isn't provided). All of the other tanks have the pickup to attach to the fuel transfer pump system (cheap electric pump, and a small Racor) All you need is a multiple position valve to select which tank to fill the day tank from, or maybe several small valves in line. The biggest challenge will be how to fill them all at the fuel dock.

The danger is overfilling the day tank and having a fuel spill. For that reason I'd consider using a larger tank for the day tank to make it hard to overfill. You won't be sitting in the engine room watching it, you want it to be fail safe.

I would also install a vacuum gauge in the fuel line, after the main Racor filter, where you can see it when the engine is running. Gives you a lot of warning to change the filters. You can get a Racor gauge, with the proper markings, at West Marine.

I'll suggest a welded aluminum angle platform, like a picture frame, which can trap the tanks securely, and will not ever rot. But wood will work fine too. Having a fuel tank come lose in rough seas would ruin your day.

I do not keep my tanks anywhere near full, and condensation hasn't been a factor, I occasionally drain out a cup of fuel to see how it looks and in eight years since I put in the new tanks I have not had any water in them.

Please post some photos so we all can admire your work.

[N4QC]

Be aware that the Racor 500 filter unit may need a retrofit in order to handle the new filter elements properly. The upgrade consists of what looks like an oversized, in thickness, “o” ring.

Check the web site at http://www.designatedengineer.com for details as well as gauges for the Racor…

"Racor 500 Series Built 1997 and before may need
a Spacer if using the new Racor element 2010 S T
or P This Filter can be easy identified by the
recess at the bottom of the filter.

If not used the filter may go far down into the
housing past the hole in the suction pipe and the
filter will be bypassed. Racor Part # 15424"

Have fun,

[cct]

Thanks for the inputs guys. I'm coming up with a plan drawing right now.

Despacio:
- Can you remember the type pump you used (volume, head pressure, manufacturer, etc?)
- Great idea on the aluminum frame. I always strive for a professional looking installation on my projects. That would help alot.
- Starting with the basic frame with a raised base lip, how much more support do you suggest? The tanks are already designed for stainless straps across the top for tie downs.
- Great idea on the extra large day tank.

Jay:
- Thanks for the pic on the manifold. I'm not sure if these tanks have a return line built in or not. I have to verify.
- How much fuel is unusable in the bottom of each tank? I.E., roughly how high off the bottom is the pick up tube.

Joe:
- Thanks for the info. Actually, I've thrown out my doughnut because the filters I use won't fit in there with it in place. Good info though.

[Despacio]

Marty here (Boat name, Despacio)
The pump is a Purolator "Facet" #40109, which I got from an auto parts store, 15 gallons per hour @ 3 psi (or is it 7?), the filter is a Racor 120A, also 15 gallons per hour. I have become aware that the Racor 500 we all have is way oversized for our engines, and that 120A is a more appropriate size, cheaper, and far easier to deal with. A Ford Lehman will never use 15 gallons an hour.

A stainless steel (or plastic) strap across the top of the tank would be plenty with the raised lip all around.

The photo:
The top hoses run to the different sides, where the lines are connected with the fuel return fittings, the valve selects which side it goes to, the hose leading down has a "T" to pick up the fuel from either side. That is selected by a small brass valve where each hose attaches to the tank. I can move the fuel anywhere, including in circles if I want to run it through the filter.

That water tank is the one I had a leak in, so the tiles have been removed by the previous owner doing a failed attempt at repairing it. No, not very attractive.

A thought:
With diesel you don't want to suck up any air, and that pickup might do that with low fuel level and the boat rolling. Are the tanks baffled for diesel? I'd ask the tank people about those issues. They say the tanks are for diesel, so maybe there's no problem.

I used one 18 gallon tank temporarily when I was having my tanks made, and this was a problem. Engine cut out right as I approached the breakwater entrance. Fastest bleed job you have ever seen. I keep a 1/2 inch wrench next to the injector pump ever since.

[N4QC]

Be careful with the calculation for a fuel filter size. If there is a return flow to the tank for the excess fuel pumped to the injectors then the pumping capacity of the fuel pump should be the over riding consideration. In my case the fuel consumption rate at WOT is about 8 to 9 gph. Whereas the fuel pump rating is in the order of 26 gph. Thus there is about 26 gph going thru the filter not just the 8 or 9…

Have fun,

[Despacio]

I'm only using that filter on the transfer system. But if I were putting in a new filter, it would be the 120A or 120B. Love the screw on cartridge.

[cct]

Marty:
Thanks for the info. The great thing about these forums is the sharing and learning from others. I've been rethinking the smaller tank bank in lieu of the 2x58 gal tank option. I was concerned about the cavitation issue along with the maintenance of needing to transfer fuel between tanks at inopportune times. I read where Scott went with the 2x58 gal option and that just be the right compromise. I do like your built in scrubber option and after brushing up on my spanish, I had to chuckle at your handle too.

Scott:
Got any pics to share on how you did your mounts?

[jleonard]

Be careful with the calculation for a fuel filter size. If there is a return flow to the tank for the excess fuel pumped to the injectors then the pumping capacity of the fuel pump should be the over riding consideration. In my case the fuel consumption rate at WOT is about 8 to 9 gph. Whereas the fuel pump rating is in the order of 26 gph. Thus there is about 26 gph going thru the filter not just the 8 or 9…

Have fun,

For a Ford-Lehman yuou can 0 as the return fuel flow. These engines return almost nothing.

[psneeld]

Be careful with the calculation for a fuel filter size. If there is a return flow to the tank for the excess fuel pumped to the injectors then the pumping capacity of the fuel pump should be the over riding consideration. In my case the fuel consumption rate at WOT is about 8 to 9 gph. Whereas the fuel pump rating is in the order of 26 gph. Thus there is about 26 gph going thru the filter not just the 8 or 9…

Have fun,

For a Ford-Lehman yuou can 0 as the return fuel flow. These engines return almost nothing.

agreed...what I read and what I observed on my pre-manifold test...that's why I decided to just plumb back to the supply manifold (as someone had posted their boat was setup) nstead of a return to the fuel tank.

[Greatlaker221]

I am replacing my fuel tanks too! What fun! Here is a link to the pictures and my blog on the restoration of my H37DC

http://savingtortuga.blogspot.com/2014/ ... ement.html