fj40 Gas Tank

[Fryedaddy]

I bought a 77 a few months back and have since taken it down to the frame. It didn't have an engine so I've got a 4.3 to go in it's place.

My main question is about the gas tank. My tank is inside the cab and I wonder if these rigs get a gas smell inside the cab? I can have a tank fabbed to install between the rear part of the frame like a jeep. Don't want the smell in my cab, the misses wouldn't ride with me.

[FF LC FREAK]

My tank is in the cab, and I have no problems. I think the biggest complaints come from the aftermarket poly tanks. They apparently never seal right and you will get the gasoline smell in the cab. Second biggest complaint is from people that "desmog" their rig and end up not venting the tank correctly. If you are reinstalling the stock fuel system (tank and lines), I wouldn't worry about it.

Good luck!

[cruiserbrett]

I second FF LC Freak's observation. Simple fact is that toyota would never have sold any FJ40's if they smelled like gas on the dealer showroom. Something is not connected correctly, or you have pinholes in the tank. Be sure to check the evap tube to the charcoal canister that exits the body(to the underside) right by the filler neck. On my '76 the rubber grommet on the steel tube, where it exited the body, had disintegrated, and the steel tube chaffed on the steel body, resulting in a a small hole in the tube which vented the gas vapors into the cab...

[SD_rdcruzer]

X3, My 75 has no gas smell inside at all. Connect it right and you should have no smell either.

[Fryedaddy]

Alright, you guys have swayed my opnion. I don't actually have a problem not. It's torn apart, I just thought it might be a problem.

Thank you all for the help.

[mike@dw]

Originally Posted by FF LC FREAK

My tank is in the cab, and I have no problems. I think the biggest complaints come from the aftermarket poly tanks. They apparently never seal right and you will get the gasoline smell in the cab. Second biggest complaint is from people that "desmog" their rig and end up not venting the tank correctly. If you are reinstalling the stock fuel system (tank and lines), I wouldn't worry about it.

Good luck!

I get a pretty stong gas smell in my cab. Even with the top off I smell like gas after driving around for a while. I had a few exhust leaks which I fixed hoping that was the problem but the smell is still there.

I did not do the build on my 72 40, so I am not sure if the tank is aftermarket or not. Tank in under the passanger seat. The vent hose has been plugged with a bolt and just lays next to the tank. What is the proper way to route the vent hose? I was hoping to use the plugged vent hose as the return lin to the tank if/when I do EFI conversion. (This is a chevy 350 converted 40)

[cruiserbrett]

it vents to the charcoal canister. depending on what part of '72 there is a vent hose and return line hose, so be sure which on your working with.

[hammerhead]

My FJs never smell of gas from the tank. Be sure your vents are set up properly. The re are 2 lines under the console between the seats. One is a supply line and the other is a return line. The vents come from 3 different points on the tank and gather near the filler neck with a manifold which has a line trvelling forward in the frame towards the canister under the hood. As long as these lines and manifold are intact you should have no fuel smell in the cab.

[JohnnyC]

strong gas smell is a leak...either fumes...but in most cases its a gas leak...if it has a very small leak under the tank it will smell bad in the rig....if it has a bad fuel line hose coming off the tank...it will smell bad...if the sender unit is not sealed and losse it will smell bad...

in 18? years its only smell'd bad 3 times...its a good way to find out you have a problem before the problem gets out of hand...your gas leak sensor in front of your face is a very helpful tool

check lines ......check sender....take out and check the actual tank...and as others said check the vents...not nesesarily in the order

[mike@dw]

Thanks!

I did not know there was a return line in a carb system.

I do know that the vent line comming from next to the filler neck is not going to a canister under the hood, it is simply tapped off with a bolt. I assume from the 350 conversion.

I will pul the passanger seat and check everything over.

[bsevans]

Originally Posted by mike@dw

Thanks!

I did not know there was a return line in a carb system.

I do know that the vent line comming from next to the filler neck is not going to a canister under the hood, it is simply tapped off with a bolt. I assume from the 350 conversion.

I will pul the passanger seat and check everything over.

The vent line you are talking about goes from the filler neck to the tank to vent pressure as you fill the tank. I'm not sure about your year, but on my '78 there is a plastic vapor recovery tank that has 4 lines. 3 go to the tank and one goes to the charcoal canister. The one going to the charcoal canister bleeds down the pressure build-up as the gas cap is non-venting. The charcoal canister plumbs up to the carb. This reduces the emmisions as the gasious vapor is burned through the carb. My '78 has a return line from the carb that plumbs directly into the tank.

[mike@dw]

Originally Posted by bsevans

The vent line you are talking about goes from the filler neck to the tank to vent pressure as you fill the tank. I'm not sure about your year, but on my '78 there is a plastic vapor recovery tank that has 4 lines. 3 go to the tank and one goes to the charcoal canister. The one going to the charcoal canister bleeds down the pressure build-up as the gas cap is non-venting. The charcoal canister plumbs up to the carb. This reduces the emmisions as the gasious vapor is burned through the carb. My '78 has a return line from the carb that plumbs directly into the tank.

If the vent line is the one going to the filler neck, then that is not the one I was speaking of. I do have the line from the filler neck to the tank in place. Right next to that I have a line that is capped off. I will have to go back and look at the lines again. With the info I have gotten in this thread, I am guessing that I have the vent line, feed line, and return line intact. What I bet is capped is the line that normally would go to the charcol canister, which might have been bypassed when the 350 was put in since all emission items seem to have been removed from this rig.

[bsevans]

Originally Posted by mike@dw

If the vent line is the one going to the filler neck, then that is not the one I was speaking of. I do have the line from the filler neck to the tank in place. Right next to that I have a line that is capped off. I will have to go back and look at the lines again. With the info I have gotten in this thread, I am guessing that I have the vent line, feed line, and return line intact. What I bet is capped is the line that normally would go to the charcol canister, which might have been bypassed when the 350 was put in since all emission items seem to have been removed from this rig.

The line that goes to the charcoal canister goes from a hose to a metal line that goes through the floor and then routes to the charcoal canister.

[mike@dw]

Ok, I have done some more investigating.

My 40 has a 350, and all the emissions has been removed including the charcoal canister. They way it is set up is just a single feed line to the carb. No return line and no venting system. There are a total of 3 lines coming out of the tank that are capped off. Those three caped off lines I am assuming are the return and the two venting lines for the emissions. I would also guess that the gas cap is not a venting type cap either.

I think this is the reason behind the gas smell. I think I either need to rig up a line to a home made charcoal canister or get a venting gas cap. The vapors have to go somewhere, and right now they are just seeping out and getting into the cab.

[bsevans]

Originally Posted by mike@dw

Ok, I have done some more investigating.

My 40 has a 350, and all the emissions has been removed including the charcoal canister. They way it is set up is just a single feed line to the carb. No return line and no venting system. There are a total of 3 lines coming out of the tank that are capped off. Those three caped off lines I am assuming are the return and the two venting lines for the emissions. I would also guess that the gas cap is not a venting type cap either.

I think this is the reason behind the gas smell. I think I either need to rig up a line to a home made charcoal canister or get a venting gas cap. The vapors have to go somewhere, and right now they are just seeping out and getting into the cab.

If you find a venting gas cap that properly fits, then post up the part number. I looked for one and none of the major suppliers made one. Here in Tucson and Phoenix one would need to hold on to the factory cap as a cap that vents will fail inspection They pressure check every gas cap. You must make sure that you do not drain gas into a charcoal canister. That is the reason the vapor recovery tank had the three lines that are capped going to the bottom of the vapor recovery tank and the line going to the canister was attached to the top of the tank. I recently replaced my vapor recovery tank due to a cracked port which allowed gas vapor into the cab. These threads will show you the basic arrangment of the ports.

Custom Vapor Recovery Tank

Factory Fuel Recovery

[mike@dw]

Originally Posted by bsevans

If you find a venting gas cap that properly fits, then post up the part number. I looked for one and none of the major suppliers made one. Here in Tucson and Phoenix one would need to hold on to the factory cap as a cap that vents will fail inspection They pressure check every gas cap. You must make sure that you do not drain gas into a charcoal canister. That is the reason the vapor recovery tank had the three lines that are capped going to the bottom of the vapor recovery tank and the line going to the canister was attached to the top of the tank. I recently replaced my vapor recovery tank due to a cracked port which allowed gas vapor into the cab. These threads will show you the basic arrangment of the ports.

Custom Vapor Recovery Tank

Factory Fuel Recovery

Found this napa PN in a search on this forum, 703-1034. I also could not find a 40 specific venting cap, but supposedly this napa one fits correctly on a 73, so I hope it works on a 72. I already called Napa and they are only $5.99 so it won't hurt to try.

[theo]

Originally Posted by mike@dw

Found this napa PN in a search on this forum, 703-1034. I also could not find a 40 specific venting cap, but supposedly this napa one fits correctly on a 73, so I hope it works on a 72. I already called Napa and they are only $5.99 so it won't hurt to try.

Same here pretty much. Went to NAPA and bought a vented cap, then walked out to the parking lot and put it on.

More often than not it's a grand thing to live in Montana and be 10 years or more behind the times.

[sggoat]

My 77 has all the original hoses, etc. I have the smell also. I'm thinking in addition to all the thread suggestions that the canister is saturated. Is there anyplace that sells a replacement canister, or can you just replace the charcoal? I'm planning to replace all the hoses/gaskets also.

Gary

[aggiecruiser]

I am about to reinstall a tank in a 1/79 FJ40, took pictures, but as always, I am having trouble remembering which of the hoses go to where based on my crappy pics...

Does anybody have a simple diagram they could post up showing which lines go from the tank to the charcoal cannister, and which lines are to and from engine.

As I look a the tank, I see the main filler neck, plus three small tubes all right next to the tank. Then I see two others that are situated at the driver side forward corner of the tank when installed in the vehicle. The are what appears to be the fuel pickup and return, correct? That's why they are attached via a bolted connection, the sump for the tank?

Just can't remember how the lines interface the charcoal cannister...

I tried sor.com, but the pics are still a bit questionable.

Thanks,
Chris

[bsevans]

Originally Posted by aggiecruiser

I am about to reinstall a tank in a 1/79 FJ40, took pictures, but as always, I am having trouble remembering which of the hoses go to where based on my crappy pics...

Does anybody have a simple diagram they could post up showing which lines go from the tank to the charcoal cannister, and which lines are to and from engine.

As I look a the tank, I see the main filler neck, plus three small tubes all right next to the tank. Then I see two others that are situated at the driver side forward corner of the tank when installed in the vehicle. The are what appears to be the fuel pickup and return, correct? That's why they are attached via a bolted connection, the sump for the tank?

Just can't remember how the lines interface the charcoal cannister...

I tried sor.com, but the pics are still a bit questionable.

Thanks,
Chris

None of the lines from the tank go to the canister. The top line from the vapor recovery tank goes to the canister.

Item 45

Item 45 is the vapor recovery tank and the line to the canister is located on the top or upper portion of the plastic tank.

[aggiecruiser]

Where does item 40 lead to? I am assuming item 46 plugs those three lines onto the three leads from the tank, correct?

And item 56 are the main lines leading to the engine, right? One to the engine, and one return line, correct?

[bsevans]

Originally Posted by aggiecruiser

Where does item 40 lead to? I am assuming item 46 plugs those three lines onto the three leads from the tank, correct?

And item 56 are the main lines leading to the engine, right? One to the engine, and one return line, correct?

I'm not sure that item 40 is anything but a check valve. My 40 is an 8/78 and does not have item 40. I'm assuming that you meant item 45 not 46. Item 45 is attached to the three ports on the tank with 1/4" fuel line. Again, someone else will have to speakup about item 56, the fuel suction tube, as my tank does not use one. The picture of item 56 shows two external ports. I assume that one is for return and the other one for supply.

[aggiecruiser]

Originally Posted by bsevans

I'm not sure that item 40 is anything but a check valve. My 40 is an 8/78 and does not have item 40. I'm assuming that you meant item 45 not 46. Item 45 is attached to the three ports on the tank with 1/4" fuel line. Again, someone else will have to speakup about item 56, the fuel suction tube, as my tank does not use one. The picture of item 56 shows two external ports. I assume that one is for return and the other one for supply.

Thanks for the reply. If your rig doens't have item 40, then where does that line lead to off of your vapor return manifold? Is the line just stubbed back into the tank with no check valve? And please excuse my ignorance, but what does a check valve do anyways? I plan on going with a TBI on my SBC so I will need to utilize both the main suction line and the return line. My main concern revovles around the vapor return system, and it's function.

Thanks again guys.
Chris

[Rocky_LC]

My '74 (October '74) had an Item #40.

I got it from C-Dan at the cost of ~32.60$. It is a fuel check valve. It mounts between the hardline going to the charcoal canister and the fuel separator.

It is Toyota P/N 90917-10012

I have also heard you can buy a "generic" fuel check valve at NAPA for about $6 that does the same thing.

The body of my old chuck valve had cracked, and that was where my "gas vapor in the cab" fuel smell was coming from.

Be carefull when removing / connecting lines to that plastic fuel separator. BSEvans has an nice replacement (and certainly worth what he paid for it), but $0R wants something outrageous ($45) for those cheesy plastic fuel separators that they pull out of scrapped 40's. I would feel really ripped off if I had to pay $45 for one of those.

Rocky
Rocky