Auxiliary Fuel Tanks for 200s (1 Viewer)

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That is how mine functions. But, as an important cavet, you need to be careful that it does not flood the charcoal canister. The kit has you relocate the charcoal canister to inside the passenger rear wheel well. I noticed that I was getting a strong fuel smell at times. Working with Walt, we figured out that that charcoal cannister had been flooded and then clogged with dirt. It resulted in a lot of pressure in the main tank -- manifest when opening the lid when at altitude. Just watch for this issue if you have been "cycling" fuel from the primary tank back to the secondary tank when forgetting to turn off the pump. I had to replace my charcoal cannister as it was totally clogged.

NOTE: I ended up relocating my charcoal cannister away from the rear tire well.

Cheers!
-EconomistAZ

My 12. 5 gallon tank did not have me relocate the charcoal canister. I believe the instructions have you relocate the charcoal canister air filter to the right rear wheel well and plumb it inline with the filter supplied in the kit. Another mud member (maybe radman?) said you can delete the charcoal canister filter altogether and that is what I did.
 
That is how mine functions. But, as an important cavet, you need to be careful that it does not flood the charcoal canister. The kit has you relocate the charcoal canister to inside the passenger rear wheel well. I noticed that I was getting a strong fuel smell at times. Working with Walt, we figured out that that charcoal cannister had been flooded and then clogged with dirt. It resulted in a lot of pressure in the main tank -- manifest when opening the lid when at altitude. Just watch for this issue if you have been "cycling" fuel from the primary tank back to the secondary tank when forgetting to turn off the pump. I had to replace my charcoal cannister as it was totally clogged.

NOTE: I ended up relocating my charcoal cannister away from the rear tire well.

Cheers!
-EconomistAZ
Any pics or more info about where you relocated it to? I need to install my tank one of these days and have been collecting advice and tips.
 
ohsix is correct. The relocation is to the charcoal canister AIR FILTER, not the cannister itself. My bad. I moved the air filter up to the engine compartment to get it high up. The jury is still out on if that is a good idea or not. My last trip had a lot of fumes up there and I am not comfortable with fumes in the engine bay. Looking at a different spot now...
 
Gotcha. I was curious if the larger tanks did require relocation of the charcoal canister.

I think I may swap my 12.5 gallon for a 24 if I ever come up with a good solution for storing the spare tire inside the vehicle. I went with the 12.5 to avoid putting the spare on my rear bumper (already tried that and got tired of swinging it to open the rear), but I'm a little concerned with how low the spare hangs now.
 
Filter should be plumbed high. Gas vapors are heavier than air so keeping it at a high point will keep vapors at bay. I have it mounted behind the fill inlet.

I'm tempted to reconfigure it actually. I still fail to understand why it is plumped to atmospheric as stock has this breather plumbed into the fill neck. I believe this may be a cause for the slow main tank fill issue many of us are experiencing. It would be as easy as T'ing into the nipples there if I ever get around to it.

1611341045436.png
 
ohsix, Land Cruiser Phil used to make a bracket that mounts the spare inside. I do not have one, but you may want to check it out. I have several of his other products and they are all top notch.

Here is the link to his website. You might contact him and see if he still has any (none on the website).


Best of luck.
EconomistAZ
 
Filter should be plumbed high. Gas vapors are heavier than air so keeping it at a high point will keep vapors at bay. I have it mounted behind the fill inlet.

I'm tempted to reconfigure it actually. I still fail to understand why it is plumped to atmospheric as stock has this breather plumbed into the fill neck. I believe this may be a cause for the slow main tank fill issue many of us are experiencing. It would be as easy as T'ing into the nipples there if I ever get around to it.

View attachment 2561481
In stock form, doesn't it breathe through the charcoal canister filter? If you plumbed it back to the fill neck, I think you would have a sealed system creating a vacuum on both tanks as you used fuel.

Edit: my post above assumes you have eliminated the the charcoal canister air filter and a sealed gas cap.
 
Filter should be plumbed high. Gas vapors are heavier than air so keeping it at a high point will keep vapors at bay. I have it mounted behind the fill inlet.

I'm tempted to reconfigure it actually. I still fail to understand why it is plumped to atmospheric as stock has this breather plumbed into the fill neck. I believe this may be a cause for the slow main tank fill issue many of us are experiencing. It would be as easy as T'ing into the nipples there if I ever get around to it.

View attachment 2561481

That is where I had mine originally. The cannister flooded and pushed fuel up through that filter. Once the filter clogged with dust/mud, I had the issue with the main tank in an overpressure state. Walt (with LRA) was super helpful figuring this out. He even offered to have one of his tech guys take a look. In the end, the charcoal cannister was so clogged up with a fuel/mud mix that it no longer functioned. Relocating that filter to the engine bay definitely solved the clogging problem, but I am not comfortable with it venting fumes into the engine bay. I am all ears for other suggestions...
 
In stock form, doesn't it breathe through the charcoal canister filter? If you plumbed it back to the fill neck, I think you would have a sealed system creating a vacuum on both tanks as you used fuel.

Edit: my post above assumes you have eliminated the the charcoal canister air filter and a sealed gas cap.

Last time I traced it, the stock setup is closed and plumbed in this fashion so it shouldn't create a vacuum. There's something not exactly right with the breather setup to the main tank such that it can't be filled at full bore. At least with the sensitive CA vacuum vapor recovery nozzles at the fuel station.

1611344060347.png



That is where I had mine originally. The cannister flooded and pushed fuel up through that filter. Once the filter clogged with dust/mud, I had the issue with the main tank in an overpressure state. Walt (with LRA) was super helpful figuring this out. He even offered to have one of his tech guys take a look. In the end, the charcoal cannister was so clogged up with a fuel/mud mix that it no longer functioned. Relocating that filter to the engine bay definitely solved the clogging problem, but I am not comfortable with it venting fumes into the engine bay. I am all ears for other suggestions...

Interesting. Do you have a sense of what caused the cannister to flood? Aux pump left on? Wheeling at altitude? Overfill gas tank?

Good info and you prob won't be the last to experience this.
 
As near as I can tell, it was from a full aux tank at altitude. I don't think I ever overfilled, but the lag in the factory gauge may have fooled me on a couple of occasions. The first time I noticed the fuel smell was with a full aux tank, parked at a bit of an angle near Lake Powell. It dripped slowly all night from the Aux into the main tank. Kind of like a Chinese Water Torture (if we are still allowed to say such a thing...)
 
Last time I traced it, the stock setup is closed and plumbed in this fashion so it shouldn't create a vacuum. There's something not exactly right with the breather setup to the main tank such that it can't be filled at full bore. At least with the sensitive CA vacuum vapor recovery nozzles at the fuel station.

View attachment 2561528




Interesting. Do you have a sense of what caused the cannister to flood? Aux pump left on? Wheeling at altitude? Overfill gas tank?

Good info and you prob won't be the last to experience this.
I stole this diagram for a gravity sub tank pluming Q. Thanks!
 
Last time I traced it, the stock setup is closed and plumbed in this fashion so it shouldn't create a vacuum. There's something not exactly right with the breather setup to the main tank such that it can't be filled at full bore. At least with the sensitive CA vacuum vapor recovery nozzles at the fuel station.

View attachment 2561528




Interesting. Do you have a sense of what caused the cannister to flood? Aux pump left on? Wheeling at altitude? Overfill gas tank?

Good info and you prob won't be the last to experience this.

With the LRA tank, the line I've highlighted blue ties into the line with the air filter. The part with the red X is relocated to the right rear fender and plumbed inline with the air filter according to LRA instructions, but if you do that, you have an air filter plumbed inline with an air filter which is redundant, so I discarded the OEM charcoal canister air filter and just have the one air filter that came in the LRA tank. If I were to remove that air filter and instead tie it into one of the vent lines on the LRA filler neck, the only way for makeup air (or air volume to replace the fuel removed from the tanks) to enter either tank would be through the purge line, which I'm guessing is normally closed outside or purge events.

As to why the OEM tank fills slow, I think it has to do with the relatively small fill line and long distance to the fuel tank. The small vent line probably doesn't help either. I fill my OEM tank with the nozzle on the 1st catch/notch on nozzles with 2 catches and on the 2nd catch on nozzles with 3 catches. If I use the last catch, the nozzle auto-stops due to vapor buildup in the filler neck. The vapor is building up due to gas entering the OEM fill line faster than it can exit the line into the OEM tank. My OEM tank fills at the same rate before and after installation of the LRA tank.

Inked1611344060347_LI.jpg
 
With the LRA tank, the line I've highlighted blue ties into the line with the air filter. The part with the red X is relocated to the right rear fender and plumbed inline with the air filter according to LRA instructions, but if you do that, you have an air filter plumbed inline with an air filter which is redundant, so I discarded the OEM charcoal canister air filter and just have the one air filter that came in the LRA tank. If I were to remove that air filter and instead tie it into one of the vent lines on the LRA filler neck, the only way for makeup air (or air volume to replace the fuel removed from the tanks) to enter either tank would be through the purge line, which I'm guessing is normally closed outside or purge events.

As to why the OEM tank fills slow, I think it has to do with the relatively small fill line and long distance to the fuel tank. The small vent line probably doesn't help either. I fill my OEM tank with the nozzle on the 1st catch/notch on nozzles with 2 catches and on the 2nd catch on nozzles with 3 catches. If I use the last catch, the nozzle auto-stops due to vapor buildup in the filler neck. The vapor is building up due to gas entering the OEM fill line faster than it can exit the line into the OEM tank. My OEM tank fills at the same rate before and after installation of the LRA tank.

View attachment 2561587

Yup, all correct.

To clarify for others, that Air Inlet Line coming off the Canister is where we have the filter open to air in the LRA install (inset pic). In the stock configuration, this line is plumped to the fill neck.

Of interest - Follow the vent line from the Canister to the Fuel Tank. Note the Fuel Cutoff Valve float in the tank. IMO, that is the sense line that should feedback to the Fuel Pump Nozzle when we fill gas. Because this circuit through the Canister is venting to air, it's not properly interacting with the fuel pump nozzle hence IMO, is causing the low flow and premature cutoff. Should be T'd into the fill neck as proposed in the pic.

1611426858006.png


Air Inlet Line from Canister or what I'm calling the Fuel Cutoff Line sense circuit, is the right line of 3, that are part of the stock filler neck.
1611427313210.png
 
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I figured this out a while back and I think Ward updated the install directions.

The original directions were for diesel and they open vented the aux tank, which is fine for diesel and none-USA pressurized fuel system.

I combine the breather from the aux with the breather from the main, this way both tanks pressurize while running the vehicle and when you turn it off the engine they both de-pressurize. That way the system is sealed for vapors, and you do not get vapor check codes too often.

You run a high loop in the breather so it's above the filler main area, and then when over filling the fuel will go back in the aux instead of the breather and charcoal can.

Still fills slow. I have not found a fix for that.
 
I wasn't aware there was an update to the instructions. So the revised method is to T the aux vent line? Do you recall what size that hose is?

Wonder if I can dig up the new instructions.
 
Ward will email them to you if you ask him, he has them in a PDF file.
 
My tank is from last summer, instructions labeled VER. 1 provided in the shipment. It shows using a vent filter near the filler neck. I am going to do the install one of these days, and I'd like to do it the best way possible. If there is a better approach like routing that vent line into another hose, I'd like to do that. Any advice or guidance would be very much appreciated.

@wardharris - any chance you could weigh in on this thread?
 
You can hook the aux vent up that way and just extend the hose on the main tank vent so it loops up above that fill can and back down to where it normally vents.
That way any over fill will just spill back down the aux filler hose.
 
You can hook the aux vent up that way and just extend the hose on the main tank vent so it loops up above that fill can and back down to where it normally vents.
That way any over fill will just spill back down the aux filler hose.
Any chance you have a picture? I'm having trouble visualizing it.
 
The blue line on TECKis300 diagram above, you just make that line longer and loop it over the fiiller box and zip tie it up there.

I don't have a picture.
 

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