OEM Subtank Retrofit/Install Project With Pics (1 Viewer)

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POR-15 has some stuff I think for fuel tank refinishing

How far does the pipe from the aux tank extend into the main tank?

Not 100% OEM idea but...

Was thinking a bulkhead AN fitting with o-rings could be used on the non aux main tank plate... I would use fuel safe o-rings.. I work on aircraft so I know about getting lines properly sealed on the first go round.. I just need to see if they are doing anything special with directing incoming fuel.

About the level switch. After hitting the books and consulting a family EE I can make a really simple circuit that senses the stock sender and opens and closes a relay accordingly..
 
I recommend sourcing a tank, transfer pump assembly and dual filler neck either on eBay OZ or from an Oz salvage yard.

I have several email replies from salvage yards which had these parts available when I was searching for them. If anyone is searching for these parts, email me (rather than PM), and I will forward those emails to you. One would probably need to coach them on the finer points of SeaMail, but they did indicate a willingness to ship to the States.

edit: Findapart.com.au was one of the more useful sites.
 
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How far does the pipe from the aux tank extend into the main tank? I just need to see if they are doing anything special with directing incoming fuel.

It passes through the top of the tank bracket and goes down about 3 inches. This is why I bought this part instead of modifying the US bracket, I wanted to be sure I met their minimum design spec. But it doesn't look like there's much purpose on how far in it goes.

I have several email replies from salvage yards which had these parts available when I was searching for them.

From experience on this project, I have found the Oz yards to be very picked over (likely by Man-A-Fre) and when you do find something, its 75% of a new price and the condition is "used" to say the least. All this to say, going salvage on the tank and filler neck is okay but I'd stick with new on everything else. Be careful of ECUs that have sat out in the elements, I had a couple of those show up DOA.
 
Hey Jim. This is brilliant and congrats on being nearly finished. I'm going to take a few days off this week and finish mine up. I also painted my overhead console and was actually trying to find a more useful altimeter that I could place in there since the OEM one doesn't handle below sea level (ie Death Valley) and it only goes up to 12,000 (leaving out a few US roads and huge exspanses of S America, etc.)

Anyway, thanks for all your help and advice. Hopefully in the next week or so I'll have the subtank wiring done, overhead console installed, front axle and power steering pump rebuilt, water pump replaced, and compressor hardwired and intalled. The parts are gathering dust...
 
this is amazing. the only problem i have is that i am a :banana: guy and there is no way i trust a shop to do all this work... where in texas are you? :D
 
Very impressive install.

In your searching, did you come up with a part number for the dual filler WITH the unleaded restrictor and the horizontal outputs??


You were going to put together a kit for this. Is that still on the table?

Amazing attention to detail and tracking down all the ECUs etc.


In a thirsty beast like an 80, the sub-tank has to be just about the best mod ever.
 
this is amazing. the only problem i have is that i am a :banana: guy and there is no way i trust a shop to do all this work... where in texas are you? :D

I am in Houston. If you want to discuss the details of the job so you can decide if you can do it, shoot me an email through the User Console with your phone number and we can chat.

Very impressive install.

In your searching, did you come up with a part number for the dual filler WITH the unleaded restrictor and the horizontal outputs?? You were going to put together a kit for this. Is that still on the table?

I will try and post that part/assembly number tonight. I have a draft of the install document and was thinking about shooting a DVD. Not sure there will be much demand for it though.

For those that decide to go this route, I can supply the metal mounting ring (drilled and pre-tapped for screws) that needs to be welded on the main tank to accommodate the fuel level switch.
 
For those that decide to go this route, I can supply the metal mounting ring (drilled and pre-tapped for screws) that needs to be welded on the main tank to accommodate the fuel level switch.

If you Include without extra charge the dual filler neck and the subtank then I am game:grinpimp:



Just kidding..... April´s fool day :cheers:
 
Ok, I have recieved numerous emails about the difference in wiring. On a 94 truck, The drivers side floor harness ends at the drivers side kickpanel with Id1, Id2 and Id3 connectors. On the 97 model there are Id1, ID2, Id3 AND Id4. Id4 has all the wires for the subtank system. Id1 is the 20 pin plug, Id2 is the 22 pin plug, Id3 is a 14 pin plug. My wiring on my 94 involved inserting female ends into the female plug of Id3 and running the wires accordingly. I spliced the black and blue wire into slot 5 on the 26-pin dark gray “B” connector on the ABS ECU, this supplies a signal to data link connector in the firewall. Then spliced the black and red wire to ECU fuse, this supplies power to the ECU. Then I ran a yellow and blue wire to connector D, pin 5, on the combination meter for the charge light signal the ECU requires to initiate transfer. Then the last two pink and pink yellow wires over to where the subtank switch will be. The pink is for power and the pink yellow is for the status light on the switch. On the 94, the female end is already filled for the transfer pump assembely, and power to the ECU circuit as well as the ground.
 
Not that you are hurting to put food on the table...but imagine if your Cruiser knowledge could be harnessed and used to make money, or energy, or beer...:beer:
 
On the 97 model there are Id1, ID2, Id3 AND Id4. Id4 has all the wires for the subtank system.

See newly inserted picture in Post #1, Kick Panel Wiring:

In the case of my '97, here are the wires (plug name, color code, slot, purpose) involved from the floor harness, all of which I brought into a new Toyota connector I called ID5:

From ID3, P, slot 7. Dash switch to ECU.
From ID3, P-B, slot 8. Oz EWD says fuel filter light...not used on petrol models
From ID3, B-R, slot 10. Will connect to wire previously run from fuse block ECU-B fuse.
From IL4 (the dead end connector), B-L, Needs to be extracted and connected to the D1 Data Link Connector by way of a tap into slot 5 of connector "B" on the ABS ECU (also located in the kick panel.)
From IL4 (the dead-end floor harness connector) the FIRST Y-L wire. Per the master diagram this connects to the “CHARGE” light on the Combination Meter.
From ID1, Y-L, slot 21. The SECOND Y-L wire. This runs from the subtank and carries the “tank level ” signal up to the overhead console.
From ID3, P-G, slot 9. Dash switch.

Also the main wiring diagram suggests a Y-R wire running from the ECU to the main fuel gauge light. This is already present in ID1, Y-R, slot 17, fuel sender. No extraction or modification necessary as it is already wired from the rear through the ECU connector and up to the combination meter. It also calls for a B-W wire for ECU power...this too is already in place and not necessary to be tapped into or run.

The P-G wire shows as P-B on the master diagram and is actually P-L on my 1994 donor pigtail. On my 1997 US truck it is P-G at the ECU connector and P-G when it enters ID3.

This stuff is simple to beep out if you have an ohmmeter. Once you confirm which wires you need, just extract them from the connectors using the approved Toyota method and group them all into a new 10 or 12-pin Toyota housing. Then your power, overhead gauge level, dash switching, ground, DLC and charge light wires all come from those respective sources into the other side of your new connector. You don't have to have an overhead gauge for this to work.
 
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I installed my sub-tank, sourced from SOR, several years ago (minus your cool OEM control system). On my setup, the fill pipe diameter on the sub-tank is smaller than the diameter of the main tank and that of the filler neck assembly. This required me to rig up a sleeve to slide into the tubing between the sub-tank and the fill neck. Does your setup also have different pipe diameters of the sub-tank and fill neck? If so, is there a reducer or increaser to accommodate this.
 
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Does your setup also have different pipe diameters of the sub-tank and fill neck? If so, is there a reducer or increaser to accomodate this.

Nope, mine are both the same size and the OEM hoses fit perfectly, though I had to remove about 1" in length on the hose between the filler neck and subtank.
 
so i wanna do this install on my 94, if i can get the proper, jdm or oz spec tank with the proper hole on the top is there any additional parts from ur list i need to get, these are the parts i have so far

80 series subtank, dual filler, tank straps, overhead console w/gauges, t-fitting, 5 rivnuts, transfer pump assembly, subtank dash switch,

.....so what i'm asking is for a list of oem parts i'd need to order, and feel free to cut paste from the list but yaa......please help, again awsome install u guys

also....does the JDM/OZ SPEC main tank mount the same way or would i need additional parts for that?
 
so i wanna do this install on my 94, if i can get the proper, jdm or oz spec tank with the proper hole on the top

- I'd suggest you locate, price and arrange for that main tank first if you would rather go that way. Dave Stedman can get you a new one. Its going to cost you a lot more to go that route than to buy my ring and have a tank shop install the switch. Your call, but if you can survive the cost of getting a main tank, that's the first hurdle.

- You need an ECU. New they are ~$240 from Japan and used they range from $150-200 in Oz salvage yards.

- You mention a t-fitting but if you are going to go to the trouble of getting a non-USA tank, you need to get the fuel pump bracket (shown in post #1) that accepts the fuel supply line from the subtank and avoid teeing into any lines.

- You need to make sure your dash switch is the 7 pin model. If you can locate the female connector PN 90980-10801, that will help. You will also either need to find a Toyota wiring harness for donor male/female wiring ends, or you'll have to buy lots of splices and they are $$.

- Your tank will fit, so I wouldn't worry about that. But you do need to confirm that you have the right petrol sender. Threads here on Mud about that. PN 83320-69215

- You need to decide if you are going to cut your main tank pipe or replace it with a non-USA fill pipe.

80 series subtank, dual filler, tank straps, overhead console w/gauges, t-fitting, 5 rivnuts, transfer pump assembly, subtank dash switch,

There is probably never going to be a turn-key " parts list" simply because every truck is different pre and post 95, USA or non, and petrol or diesel. But if you work against this thread and the others here, you will finally get everything together where you can start. I'd do it in sections, the wiring first, followed by the transfer pump/solenoid install. Then I'd get the subtank rivnuts in and testfit that. You'll do the the subtank, fillerneck and main pipe cut at the same time because of the hoses and the need to not have any open plumbing. Last step would be to do the main tank, run your supply line and then test your circuits with the ECU.

FYI, we are hearing that the #3 rear floor subtank-to-rear crossmember wire (about 18 inches long) PN 82169-60020 is no longer available. No biggie but you'll just need to do some simple custom wiring if you don't have that with your tank.
 
A couple of technical questions

Jim,

Thanks a million for posting all this info on the subtank install. I have a couple of technical questions to ask about your install, would you prefer I ask them in the thread or by email?

Thanks,

-Danny
 
Nicely done Jim. Thanks for this and other contributions to the overall knowledge of the 80-Series and, in particular, to the sub-tank knowledge.

-B-
 

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