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Existential Angst[_2_] Existential Angst[_2_] is offline
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Default Solved: Vehicle fuel pump as a transfer pump

"The Daring Dufas" wrote in message
...
On 1/26/2013 3:43 PM, Existential Angst wrote:
"bob haller" wrote in message
...
On Jan 26, 3:35 pm, "Existential Angst" wrote:
Awl --

Thanks to Bob Haller -- and other input, of course -- I found a dert
simple
way to do this, with no ill effects to the car's pyooter or anything
else.

Rather than fool with the pressurized supply line (the shrader valve bob
spoke of), I found the *return line* to the gas tank, and used that
line.
You can distinguish the two by squeezing either with a pliers -- the
supply
line (to the engine) will shut down the engine in very short order,
while
the return line back to the tank does not. In fact, squeezing the return
line speeds the engine up slightly, which makes sense.

Now, in this scenario (running the engine), you wouldn't want to use the
supply line to the engine, bec you could easily starve the engine of
fuel
in
this transfer process, whereas the return line to the tank does not
affect
the engine one whit.
However, if you are careful, you might have better results from the
pressurized supply line, being watchful of the engine idle. I opted for
the
"safer" return line.

So I cut the return line (the short section that is rubber), turned on
the
engine, and lo and behold, boucou fuel -- on the order of a quart in
about
20 secs. For the benefit of the Butt Bros George and JoeBlow, dats 3 qts
per min, 3/4 gal/min, or about 45 gals/hr -- not too bad. I hope the
Butt
Bros were able to follow that.....

Now, the other scenario is, if you are able to jump the fuel pump (which
seems to operate off a relay), then you can tap into either line, cuz
you
don't need to turn the engine on. You may get a higher flow rate by
using
the supply line with the engine off. And some cars may start the fuel
pump
just with the ignition on, which would be nice for this.

So after filling a qt, I hose-clamped the tube together with a barbed
coupling, until I can put in a T + ball valve.
This hose is hose-clamped at either end to metal tubing anyway, no fancy
fittings like on the pressureized supply.
If I can jump the fuel pump relay, I might fool around with the
pressurized
side, but the fittings on the end are pretty substantial, so the hose
may
not be amenable to simple hose-clamping -- altho both the supply and
return
hoses appear to be the same type of hose.

So this is a really elegant solution to transfering gas, at least from
the
truck to some other vessel. I'll figger out a way to nicely transfer
stored
gas to the truck, and it seems like a submersible automotive fuel pump
would
be a safe way to go, altho manual pumps are certainly viable.

If this works out, I may bump up my li'l doomsday storage depot to mebbe
1,000 gals.....
The Butt Bros on Doomsday: Please, Sir, may I have more gas from your
return line?????
--
EA


all the vehcles I ever owned with pumps in the tank turn the pump on
when you turn the ignition key on, after all fuel must be at the
engine at start up....

get in your vehicle, turn key, you will hear noise for a moment till
the fuel is up. its a normal part of vehicle operation..... once the
pressure gets up the pump shuts off........ all automatically.

you could probably buy a fuel pump tester with the schrader valve and
cut the pressure gauge off, and use that hose for a fuel line
================================================== =

The pump was f'sure not turning on with the ignition, but mebbe that was
because the line was already pressurized from earlier startups.

I'll test this by just separating the hoses relieving any pressure, and
see
if the pump runs on ignition only.
I might have to cut the supply side to make this work, tho. But
hopefully
it will work on the return side as well -- will proly depend on
what/where
is supplying the back pressure.


I had to drop the huge plastic gas tank on my 89 Dodge van last year to
clean the filter sock on the intake of the fuel pump which is electric
and feeds the TBI system. I found that there was an extra line capped
off that was hooked to a tube going to the bottom of the fuel tank which
I guessed was a design feature to allow mechanics to pump all the fuel out
of the gas tank before removing the tank. It was easily reached from
under the van which led me to believe what I had guessed. The return line
is designed to swirl the fuel around the pickup of the fuel pump to
prevent debris from collecting in the low spot. It's an interesting
design. I figured that drain line would be a good place to install a pump
for getting fuel or hooking up an auxiliary tank with a transfer pump like
an aircraft has. ^_^


I will check that out whenever I can get under the truck. Would be handy if
the Frontier has that, another alternative.
--
EA



TDD