Best / easiest way to empty gas tank? (1997 Series 80 Toyota Landcruiser) (2 Viewers)

[BILT4ME]

Based on the bends in the filler tubing and the baffle in the tank, I seriously doubt you could get the fuel out of the tank, even near the level of the pickup, which is above the sump bottom. Additionally, you run the risk if damaging the pickup, the filter or the sending unit, which you can't see.

If you're worried about fumes, you probably shouldn't be trying to drain the tank at all (I had a box fan running next to the tank the entire time I had it open, and the garage door was open). There is no way to remove the fuel without some vapors escaping. If you are determined to siphon the fuel, do what @george_tlc recommends and remove the 2nd row seats, pull back the carpet and after you clean off the access panel, drain the tank from above. IIRC though, you still won't be able to get all the fuel out without removing the drain plug, but you will get all but the last gallon.

If you are concerned about residue in the tank, you'll need to remove both the access panel, and the fuel pickup unit, and the drain plug, so that you can cycle cleaning fluid through the tank. Without removing the tank, you'll need several gallons, though. I tried all this when I removed my tank, after getting one of the LSBPV bracket mounting bolts lost between the tank and the skid plate. Even with the tank out of the truck and in your hands, flushing it is difficult, due to the baffle and drain orientation, without a lot of fluid.

If you're going to all this trouble, you should get a new filter. You'll have the pickup out anyway, and that's the only way to access the filter.

You had a box fan running while draining gasoline?

WTF?

That's almost an open flame.

 

[flintknapper]

The engine ran 3 or 4 months ago, but you don't think there may be varnish and what not ending up clogging up the filter or mucking up the injectors etc?

I doubt there is enough varnish to do that. Varnish occurs when the fuel evaporates. I'm betting your fuel has just 'soured'. And NEW gas will dissolve small amounts of varnish anyway. I'd be inclined to treat the fuel in the tank now AND add as much new fuel as you can fit and run it. Then change the external filter when that tank is gone. Now IF the fuel has been sitting for YEARS (not a year) that is a different story.

 

[flintknapper]

You had a box fan running while draining gasoline?

WTF?

That's almost an open flame.

I always place a large 'wetted' towel over the tank opening anytime I open a fuel tank to gain access at the fuel pump area. You want to avoid having fumes escape as much as possible in conjunction with ventilation of the area. You would NOT want a fan blowing into/over the tank, but you DO want air moving in the area you are working in so that any fumes that do escape can not concentrate.

 

[Malleus]

You had a box fan running while draining gasoline?

WTF?

That's almost an open flame.

Give me some credit; the motor is sealed.

 

[Squash]

Drive to the store for beer and Cheeto's!

 

[e9999]

Bummer that the siphon is not likely to work through the filler then.

Yup, will do any of this outside, and no, no electric motor will be running nearby. But thinking I may use air from my compressor to purge the area, that should be safe with a long airhose.

Yes, thought about adding new fuel to dilute the old one but of course if I then still end up having to empty the tank it'll be much more to deal with. If easy enough I'd rather empty it first, which is why I asked.

But I may add some fuel treatment now anyways just to limit further problems. Would a fuel stabilizer do anything? Techron? Seafoam? Something else?

 

[flintknapper]

But I may add some fuel treatment now anyways just to limit further problems. Would a fuel stabilizer do anything? Techron? Seafoam? Something else?

Nothing you can add now will 'rejuvinate' old fuel. That is why 'mixing' with new fuel is important. SeaFoam will aid in helping to 'clean' deposits in fuel lines and is also a fuel stabilizer. But once ethanol gas has phase separated the best you can do is either drain it or 'dilute' it with new fuel. If it was running before...then it will run again with new fuel on top. Do you have any idea how much fuel is in the tank now? If adding new fuel....I would think you would want at least a 50/50 mix. If that isn't possible then drain for sure.

 

[e9999]

I just fired it up for a minute to see how it runs. Started immediately, ran fine, idled smooth. Doesn't mean it's not busy clogging the filter etc up, though, of course, which I would be annoyed with since I put a new one in just a couple thousand miles ago, and that was quite an ordeal IIRC.
But now I'm thinking that if I can't easily siphon things out as was said above, it'll be about the same amount of work to do preventive emptying through the top vs cleaning things later. And there may also be no problem at all. So, maybe I'll just do what you suggested. Put in some new gas, maybe higher octane, a bunch of seafoam / Techron and take a chance with that. Turns out the tank shows close to E on the gauge but no reserve light on, so more than 5 gals probably. At least it's not full, but may still be a pain emptying.
What makes this more complicated is that I will need to run a smog test to get it back on the road, and this being the PRK, failing that test is fraught with bad consequences so I don't want to increase the risk of a fail with gunked up systems.
Sheesh, I did not plan to let it sit that long so did not put fuel stabilizer in it in the first place. And, yes, it's 10% ethanol out here.
Gotta say, it's impressive that it's running so well with old gas.

 

[e9999]

One more thing if anybody knows: is the fuel pump running with key on but engine not running? If not, is there an easy way to run the fuel pump without the engine running? Maybe just directly feeding it 12V? That way maybe I could just run it and use the outflow hose to drain the tank? So no spillage, no fumes, much better..

 

[e9999]

Looking a bit more at using the fuel pump to drain the tank.
Here is the wiring diagram for the '97:
What's with that F5 Resistor (0.7 ohm) there? What's it for? Do I understand correctly that the Fuel pump relay would bypass it when activated and the fuel pump would get the full 12V (?) when running? Or in other words I could just apply 12V directly to Pin 3 of the F18 connector without having to worry about limiting the current? And yes, I'd rather not zap the pump motor (especially in a tank full of gas... ) so inquiring minds would rather know...

 

[george_tlc]

^ You're a moderator and been on this forum forever (nearly) and don't know how to search?

The search button is at the top/right section of the website... Looks like a magnifying glass icon...

Just one hit -> 1fzfe dies on acceleration - https://forum.ih8mud.com/threads/1fzfe-dies-on-acceleration.863168/#post-9792264


Just run the effing fuel through the effing engine. Of course we know that you will need to kill/reanimate/kill/reanimate/kill... for at least another week before making a final decision on what to do

cheers,
george.

 

[e9999]

Thanks for the info George!

 

[flintknapper]

One more thing if anybody knows: is the fuel pump running with key on but engine not running? If not, is there an easy way to run the fuel pump without the engine running? Maybe just directly feeding it 12V? That way maybe I could just run it and use the outflow hose to drain the tank? So no spillage, no fumes, much better..

No fuel pump will not run (or prime) with key on. MUST be cranking to energize fuel pump. You can 'jump' the fuel pump, but honestly....I think you'd be fine with 10 gallons of new gas on top of the old, Seafoam. Run most of it...then add a good Catalytic Cleaner though it and have it smogged. Bet you'll pass no problem.

 

[e9999]

thanks Flint, inded I may end up doing that and obviously it's the easiest way to go, but not giving up quite yet if draining is not a big pain. If I can very simply drain the tank by jumping the fuel pump that might be my preferred route, just to be safe. Looked some more at the EWD. Looks like both the Circuit opening relay and Fuel pump relay are controlled separately by grounding with switching transistors in the ECM, presumably based on running or not and load conditions. From what I'm guessing looks like the resistor being bypassed is meant to increase the pump speed, maybe at higher loads. So seems like jumping the pump through the resistor rather than directly may be the safest bet since flow rate is not an issue for my drain job. And looks like the resistor is right under the hood near the antenna so should be very easy to get to. Or do it at the Fuel Pump Relay on the other side if it's easier to tap into. Now to find an easy location to open the fuel line out of the pump before the fuel filter and I may be golden.

 

[flintknapper]

thanks Flint, inded I may end up doing that and obviously it's the easiest way to go, but not giving up quite yet if draining is not a big pain. If I can very simply drain the tank by jumping the fuel pump that might be my preferred route, just to be safe. Looked some more at the EWD. Looks like both the Circuit opening relay and Fuel pump relay are controlled separately by grounding with switching transistors in the ECM, presumably based on running or not and load conditions. From what I'm guessing looks like the resistor being bypassed is meant to increase the pump speed, maybe at higher loads. So seems like jumping the pump through the resistor rather than directly may be the safest bet since flow rate is not an issue for my drain job. And looks like the resistor is right under the hood near the antenna so should be very easy to get to. Or do it at the Fuel Pump Relay on the other side if it's easier to tap into. Now to find an easy location to open the fuel line out of the pump before the fuel filter and I may be golden.

^^^^

Yes, this is my understanding of how the fuel pump operates in both the 80 and 100 series.

The pump does NOT run/prime with the key in the 'on' position, only when cranking the engine (presumably a safety feature).

After the engine starts....the fuel pump obviously switches to full time run....BUT is a variable output depending on load. This appears to be accomplished by varying the voltage going to the fuel pump.

A large amount of fuel is simply not needed (only to be returned to the tank) when at idle or low speeds. So Toyota didn't see the need to engineer 'High Blood Pressure' into the pump under these conditions. Increased pump life being the logical result.

I have the original fuel pump in my '97. 328K miles and 24 years later....still working fine.

 

[ChaseTruck]

I've been reading this thread, and get the feeling that this is about something that's really not a problem, but has great potential to needlessly turn into a problem.
If this issue were bugging me, I'd go for the siphon method from the tank access in the cab, then do a series of adding 5-10 gallons fo fresh fuel, drive the tank empty, repeat.
And by the way, (old) gasoline is an excellent herbicide. I learned that when I changed gas tanks on the '93, and spilled some on the lawn while trying to coax the last bit out of the old one... took 2 years for the grass to come back

 

[cruisermatt]

shoot a hole in the bottom of the tank with a .45

 

[cruisermatt]

You had a box fan running while draining gasoline?

WTF?

That's almost an open flame.

Oh please. I have MIG welded on gas tanks that had fuel in them the same day.

 

[BILT4ME]

Oh please. I have MIG welded on gas tanks that had fuel in them the same day.

I'll bet you have. I'll bet you also purged it with car exhaust or rinsed it with something else. You sure didn't just drain it, then fire up the welder.

I know a guy that regularly TIG's aluminum fuel tanks on semi trucks that are full of diesel. He can TIG it with the liquid fuel behind it to keep it cool and here is no oxygen gas pocket there for it to ignite.

Not the case with gasoline fumes.

Keep doing it!

 

[WarDamnEagle]

US gas but old enough (well over a year) that I'm concerned about varnish etc, plugging things up, even though the engine is running fine now. So I'm thinking that as a preventive measure I should get rid of it rather than sucking it up in the engine, and especially so since I will need to deal with a smog test shortly and I'd rather not have to deal with more cr@p on that front...

Probably will empty it, fill with a bit of fresh gas, add plenty of Techron or Seafoam and see what goes.

Year old gas (Ethanol 10%) has probably phase separated....BUT if there isn't a lot of it in there...you can add some SeaFoam and fresh gas on top of it and run it if you don't want to mess with draining it. It should burn fine.

The engine ran 3 or 4 months ago, but you don't think there may be varnish and what not ending up clogging up the filter or mucking up the injectors etc?

I've been reading this thread, and get the feeling that this is about something that's really not a problem, but has great potential to needlessly turn into a problem.
If this issue were bugging me, I'd go for the siphon method from the tank access in the cab, then do a series of adding 5-10 gallons fo fresh fuel, drive the tank empty, repeat.
And by the way, (old) gasoline is an excellent herbicide. I learned that when I changed gas tanks on the '93, and spilled some on the lawn while trying to coax the last bit out of the old one... took 2 years for the grass to come back

I leave several vehicles for over a year; usually with sea foam and a full tank but sometimes not. I think you're overthinking the gas issue. Pour in a can of sea foam, top off the tank with 93 and drive it.