OEM Subtank Retrofit/Install Project With Pics (42 Viewers)

[CycloSteve]

Chris, that does look like a pretty clean tank. It also looks like a 100 series one, which is slightly different, but should be fine from what I understand. Is the eBay seller sending you any of the other bits and pieces, or just pulling out of the deal? What a pain.



Steve

 

[chrisc16]

Oh shoot, a 100-series tank, really? I guess it's not exactly the same as the one on George's page. Well that stinks, sounds like I will have trouble with the straps then. Is there any documented info out there on 80-series vs. 100-series sub tanks?

The ebay seller has basically stopped communicating with me altogether. Luckily all he was offering was the tank; I already got the filler neck and pump from another seller.

-Chris

 

[CycloSteve]

All may not be lost. You will need to check with Dave at Japan4x4 to ask if the 80, 100 or 105 series straps will work with the 100 series tank (1" longer?). The level sensor on the top looks similar, and the open hole for the transfer tube looks the same. If it is the same physical dimensions L W H, it should work. Most of what I can see looks to be minor changes just to the bottom. If your spare is out already, try and test-fit it into the space.



Steve

 

[CycloSteve]

HI just finished transfering a bit more into the main and it automatically shuts off when the main tank is 75% full.
The main gauge shows a bit less than 75% when shut off occurs (see pic) and it takes several minutes for the main gauge to show 3/4 full.

Did further testing this weekend. Mine also does the 75% shut-off at the same point on the gauge; just under the 3/4 mark. Will test the subtank empty again shut-off later this week when I can pump more fuel into the main. Before filling it, though, it was not showing continuity. Will see if being wet for a few days helps.



Steve

 

[elmariachi]

Hi guys,

Sorry I have been off the radar. I will try and monitor this thread more closely and answer whatever questions you might have. Glad to see Sam, Steve and others pushing the envelope on the documentation, the progress is excellent.

Also, it does take about 15 minutes to complete a transfer. Not meant to be done in a rush, likely designed to happen while you are driving. As for the continuity issues, remember that the system is designed to be tested via the port under the hood. If you aren't getting solid readings there, the system is wired wrong. I had a hard time getting the connectors cleaned out that were under the driver side passenger door. That's where I finally found the problem that was keeping mine for working.

For AKTundra, the overhead console harness has two segments, one for the visor overhead lights. If you separate it out and re-wrap the console harness by itself, its MUCH easier to snake down the a-pillar.

Lastly, I have the Toyota MicroCat worldwide parts system on DVD. If you need any part #s verified let me know. And NO, its not able to itemize all the parts needed into a nice tidy list.

 

[CycloSteve]

Jim, would you have the part # for the Subtank "Fuel Level Switch / Gauge Sensor"? This is the one which tells the system to shut-off when the sub is empty, and also gives the level info to the console gauge. Mine is not turning off the transfer when empty, so need to source a new one from Japan4x4 and it is easier if I have the right part # to give Dave upfront.

and thanks for all the help.

Steve

 

[elmariachi]

Jim, would you have the part # for the Subtank "Fuel Level Switch / Gauge Sensor"? This is the one which tells the system to shut-off when the sub is empty
Steve

There is no subtank switch. Only the main tank has a sensor (fuel level switch/sender) and that part # is in post #1 of this thread.

Jim

 

[ParadiseCruiser]

Chris -

Oh shoot, a 100-series tank, really?

That tank appears to me to be the one used on the 105 (the straight axle version of the 100). I have a pix in my files labeled "105 subtank" that is identical to the pix you posted above.

Well that stinks, sounds like I will have trouble with the straps then.

When I originally did this mod (many years ago...), I tried to use this 105 tank. The tank fits into the space on the 80 with no issues, but the 105 tank straps are too long by just a bit to fit in the prescribed location (i.e., the holes used for the proper 80 series tank and straps). To try to shorten the straps seemed to be too much of a PIA, so I gave it up and sourced an 80 tank and straps.

BTW, I did not have 80 straps available at the time, so I don't know what the outcome would have been using them on the 105 tank.

Additionally, I'm not certain that the proper 80 subtank pickup tube, and gauge sender and level switch will fit in the 105 tank ports. I'd have to think about that a bit to be sure...

Cheers, R-

PS: There are other issues with the tank you have pictured Chris.

This so-called 100/105 tank (if that really was its application) was designed for a submersible, in-tank transfer pump. The port for the pump (larger hole) is approx 107mm (from my notes) with a 6-hole pattern. The 80 series tank I am familiar with was designed for use with an external transfer pump, using a pick-up tube in that port position that measures 83mm with a 5-hole pattern.

Additionally, the 80 v. 100 fuel gauge sender that fits in the other port may have slight differences in the float arm length between the two tanks... which might result in fuel gauge accuracy issues.

FWIW, now I recall why I gave up on that tank. Yes, it fits ok... but it would have required one kludge after another to get all of the slightly different parts working together. R -

 

[ParadiseCruiser]

Jim & Steve -

Greetings Jim! (Long time...)

I am wondering if Steve is talking about the part that Toyota calls the "Gage Assy, Fuel." That's the dual-arm OEM subtank part that has both the gauge sender float on one arm, and a separate fuel "level switch" on the other... that latter being the on-off switch that tells the ECU the tank is empty and to shut down the pump.

This is the one I have always used on my subtank - though I am using George's "ecu" as you know - not the OEM ECU. If that is the part you're asking about Steve, it's #83320-69215.

Back in the day, before George actually started building his subtank ecu for Cruiser community, I built one from scratch using George's original design (schematic). After many years of flawless service, I started having intermitant (and finally, total) subtank transfer pump start (and shut-off) failures.

Although I suspected the level switch had failed, I finally traced the problem to a failed component in the "ecu"... SO... depending upon the way your system is set up Steve, you might consider that a possibility before you start messing with the tank. YMMV, of course.

Cheers, R -

 

[CycloSteve]

Hi Ron,

Many thanks for the P/N. That is the exact component. I have tested at the switch-plug itself, and it is not working according to the FSM test procedure (does not give continuity between pins 2 and 3 when empty). The ECU appears to be fine so far.



Steve

 

[ParadiseCruiser]

Steve, another thought...

The level switch canister has a small "C" clip that can be removed so the "shell" can separated from the "lid" of the canister. Once apart, you can see if the contacts are gummed up, or the float itself is moving about freely in there.

I know it's a stretch, but if you are going to drop the tank it would easy to check before you part with the $$ for an entire new assembly.

R -

 

[CycloSteve]

Hi Ron,

Excellent idea...will pull the sensor in the next few days and give her a good cleaning and testing before ordering a new one (appx $60 from Japan). Luckily I added the OEM access panel from inside the truck so I can pull it quite quickly and easily...the tank stays in!



Steve

 

[chrisc16]

Chris -

That tank appears to me to be the one used on the 105 (the straight axle version of the 100). I have a pix in my files labeled "105 subtank" that is identical to the pix you posted above.

Thanks Ron. After consulting with Dave (japan4x4) I came to the same conclusion - while I could probably make it fit in my 80, I would have a myriad of other problems with the plumbing. I'm on the hunt for a proper 80 subtank, and will either sell this 105 subtank here on Mud or keep it for my wife's UZJ100.

Thank you for the invaluable information!

-Chris

 

[cruiserdan]

Hi Ron,

Excellent idea...will pull the sensor in the next few days and give her a good cleaning and testing before ordering a new one (appx $60 from Japan). Luckily I added the OEM access panel from inside the truck so I can pull it quite quickly and easily...the tank stays in!



Steve

I have been able to order that sender in the past. Ontario shows some but they have an odd status code. They may, or may not, accept an order from a US dealer.

 

[elmariachi]

I realize I misread Steve's question about the switch part#. FYI there were several if those still in the NA system a year ago as I think they were used in some Camrys. I think.

Ron, hope you are doing well!

 

[CycloSteve]

Well, pulled the subtank level gauge, and cleaned-out and fixed the low-level float, but also found out that the gauge-float has a broken winding, so a new one still needs to be procured.

And as a second gotcha, one of the Main Tank level sensors is not working. Have bypassed for now (using the signal to ECU pin 11 to feed pin 11 and pin 3). Both sensors give ground, and go off at the same 3/4 point of fill, so is a workable solution until I can run the tank empty, drop it and clean them out and see if it needs to be replaced or not.

So folks, test thoroughly AND clean these two sensors BEFORE installing your tank.



Steve

 

[aktundra]

Before I break out the angle grinder and cut a piece off, I wanted to see if anybody has been down this path and has a better solution.

The picture 1 shows the transfer pump and solenoid assembly as it came from AU. Transfer pump and solenoid are on a bracket, and that bracket is attached to another bracket containing plumbing. Pic 2 shows the two brackets separated, and though shot from the top, the offending tab is slightly visable in the second shot.

Many OEM sub tank installations have proceeded without the plumbing bracket piece.

It appears that the plumbing bracket serves more as a heat shield from the exhast rather than any kind of mounting bracket (plumbing can readily be routed with soft hose).

No problem mounting the Pump/Solenoid bracket to the pre threaded holes. However I have tried threading the plumbing bracket in from the rear (pic 4) between the cross member and the body. The second Pic 4 (sorry, should have been pic 5) shows the area in front of the crossmember. I have tried removing the last section of the OEM exhaust, the front strap of the main tank, and tried threading the plumbing bracket over the cross member from front to back.

I think my only option to to trim the tab off with an angle grinder. Any idea what purpose that tab serves? Anybody installed this this bracket without triming the tab, or more drastic options to get more clerence.

 

[CycloSteve]

When I installed mine, I just disassembled the two parts like you have and was able to very easily get them into the truck. I cannot recall if I went from the front or rear, but it was not a struggle to get it into place. Then bolted them back together/into the capture-nuts, drilled the additional mount holes that are not in our rigs, and it was good-to-go. The only difference I can see with yours is that you still have the rear line attached, and I did not.



Steve

 

[aktundra]

Steve, do you have a body lift ?

Cause that would certainly make things easier !

 

[CycloSteve]

No body lift. You may need to remove the filler tube to the main tank to install. Main tank too. Just a thought, as I think both of mine may have been out when I installed the transfer assembly.



Steve