I don't have a valve schedule. I mentally trace the flow several times. The set-up does all the same functions as yours.
"The engines can draw from any tank and return to any tank."
This could cause the receiving tank to become overfilled.
Where does the overfill fuel go ? Out the vent? In the bilge? , to an emergency tank?
That looks familiar
This is mine from winter 2011. Here is the thread from the build discussion: http://www.trawlerforum.com/forums/s6/fuel-system-upgrade-project-episode-ii-3761.html
Looks like the differences are: I only have a 60gph pump since that was the capacity of the filter (all transfers go thru scrubbing filter). I can scrub and transfer fuel... BUT... I have a multi-stage (1-30 micron and 1-10micron) filter system that doesn't have a "switchover" option that I see yours has. If I get a filter clog, I have to change it underway. The theory behind that was that we only use 2 GPH and do 99% inland boating. Not-to-mention I check and change filter pretty regular-like and keep my tanks clean. A catastrophic clog would be pretty rare. I've also gotten pretty good at changing them in a hurry.
Anyway, since it's installation, I added a dedicated feed to the genset and plan on adding a spigot to fill an external container with fuel for rinsing filter bodies and such. Also moved the pressure gauge to the filter closest to the engine (far left).
I kept the rig as simple as I could (thanks to a few tips from members here). I didn't want to think too hard about it and make a mistake.
Clean diesel fuel is the main way to help insure engine efficiency that the owner / operator can play a part in,
Sure , but the grunge in the fuel usually comes from the stuff stuck to the tank sidewalls and baffles.
The cleanest fuel can be mud after an hour of real bouncing in a dirty tank.
The only way to have clean fuel from an old tank is to either clean the tank, carry a couple of cases of filters , or bite the bullet and buy the centrifugal cleaner.
And with a proper fuel tank, that can be easily serviced (instead of a box of fuel)
ALL these problems would never exist.
Fuel centrifuges are good for fuel quality but wont help with the heavy sludge on the tank bottom. / Craig
What I want to know, Mark, is where did you get those manifolds, they are very cool. I looked and looked online for something like that and came up empty handed; mine were made at a local machine shop out of steel and weld-o-lets.
Remember those holes in the valve handles can be used to gang the valves.
If a 3 way pair is used it can supply fuel from a tank , and return fuel to the same tank, no thinking or fuel pickup and delivery diagrams needed.
KISS
If you're prone to making mistakes, this would be a good idea. In my system I have a return manifold and a supply manifold. The valves are for port and starboard. They're shown all open in this picture. I don't run that way, I keep either the left valves open or the right valves open. The only time I'll open a port tank return with a starboard tank supply (or visa versa) is when I'm transferring fuel with the fuel polishing system.
The one thing I have to be really careful about on this system is to keep a return line open. The mechanic who installed my engine, and this fuel system told me that with a high pressure injection system, you'll immediately destroy the injectors (and pump?) if the returns are both closed.
It's flexible, but not idiot proof.
In this picture you can also see the fuel pickup is at the bottom corner of the tank.
Nice clean set up, easy to understand and operate The fuel feed valve @ the lower corner of the fuel tank is installed very low in the tank < it looks like its lower than most > but I would guess its still 1 1/2 inches off the tank bottom, We just serviced a 300 gal tank with a very similar set up with a racor twin 900 polishing system, here is a picture of what came out of the tank,
I was concerned about that problem, but now believe that my tanks are reasonably clean. The return is at the top of the tank and on the other end. When the tanks were less than half full, I emptied one into the other and then added back in a very small amount of fuel, just enough to keep the polishing pump primed. The fuel would drop from the top of the tank to the bottom with some velocity, and then stream down to the other end. I figured that would knock something loose, but it didn't. Other than a couple of specs of gunk, the fuel came out clean.