New fuel transfer/filtering system—and a valve question

Got things hooked up yesterday for a test run and it all works perfectly. I replaced a jury-rigged collection of pipes and antiquated equipment with a new Fleetguard, Reverso pump, multi-port selector valve and hoses. With this system, I can transfer filtered fuel to the day tank before each day’s run . . . a 20-minute job while getting ready to get underway. (The Reverso on the right in the second photo is our oil change pump.)

I want to replace two valves (one at the bottom of each saddle tank) that feed the transfer/filtering system because one or both leaks through when closed. And they are a bear to get at. The leak through is actually a tiny stream when both valves are closed and one of the fittings downstream is removed. (The gravity transfer hose between tanks was connected at the time I was discovering this, so I couldn’t tell for sure which valve leaks (maybe both?).

The second last photo shows one of the valves on a nipple coming from the stbd tank. A hose barb goes on the capped Tee and routes fuel to the new transfer pump and filter. The open flare fitting at the bottom is for the gravity transfer hose the P/O used for boat trim. I was thinking of removing this fitting and adding a simple drain valve and plug to quickly test for water and sludge. (We never use the gravity transfer hose—we keep the boat trimmed using the transfer pump and alternating supply tanks as needed.)

I tried to get the valve pictured off yesterday using a pipe wrench and vice grips twisting in opposite directions, but it’s really hard to get at and I couldn’t apply full force. Thought I’d try again with two pipe wrenches and pieces of pipe over the handles to increase torque but I’m a little worried about spinning the nipple where it connects to the tank. If it’s threaded (as it seems to be in the last photo) it would be no problem to reinstall. But if it’s welded or rusted to the tank and I twist I it off, I’m screwed . . . boned . . . F‘d . . . even though both saddle tanks are currently empty.

Would appreciate any thoughts on removing these valves (not sure I should apply heat around diesel tanks— even if mostly empty). Also, any reason to keep the gravity transfer hose?

As always, thanks for all ideas.

Sometimes it's important to evaluate risk versus gain. While I assume the tank is threaded, irrevocably damaging threads would give me pause. Another solution would be to install a valve in the transfer hose or replace the hose barb with a bleed valve like what are common on engine blocks. If you plan to use it as a sampling port, double valving it would be my choice and more likely to be used do to less effort.

Ted

O C Diver said:

Sometimes it's important to evaluate risk versus gain. While I assume the tank is threaded, irrevocably damaging threads would give me pause. Another solution would be to install a valve in the transfer hose or replace the hose barb with a bleed valve like what are common on engine blocks. If you plan to use it as a sampling port, double valving it would be my choice and more likely to be used do to less effort.

Ted

Click to expand...

I like your logic, Ted. My only concern would be having that valve leak (slowly) into the hoses and (somehow) a hose leaks. Very unlikely, I know, but the consequences would be pretty dire. Still, I need to weigh the risks, as you wisely note.

Another option would be to:

1) lose the crossover hose and flare fittings.
2) replace the lower Tee with an el.
3) install a new valve on the tee.

This would put two valves directly in line . . . but I could leave the upstream valve open and close the line off with the new valve.

Don’t know why this didn’t come up before but I think I like it.

I'm with Ted on this. I mean, you seem to know what you want to accomplish, but the phrase "two pipe wrenches and pieces of pipe over the handles to increase torque" and the possibility of causing a tank problem which would be very difficult to correct would give me pause. Is there a less "scary" way?

Ken

I'm also with Ken above.

You just installed a new transfer system with hoses. They could leak too!

Hoses are easy to replace. Don't take a chance with the fuel tank fitting.

You guys convinced me. I ordered some additional fittings today and will use the two-valves-in-line approach outlined in post 3. No pipe wrenches or extra torque .