Hello Everyone. I picked up this fuel tank for my FJ40 yesterday. I currently have a rear conferr gas tank. I don’t have the original tank. This tank would go under both seats. I don’t see a breather on this tank and wanted to get your thoughts if I needed one to install this. I only see 2 ports one for fuel in and the other to my carb
FJ40 underseat gas tank help (6 Viewers)
- Thread starter dvoraully
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Fuel cap is only breather on my 45s
- Thread starter
- #3
Vented
I have never seen a tank like that - home built diamond plate aluminium? Yea I would think it needs a vented cap or it runs out of fuel is the tank builds enough vacuum to resist the fuel pump being able to suck.
I see 2 fill ports and a big hole for a sender unit
I see 2 fill ports and a big hole for a sender unit
- Thread starter
- #6
Not sure yet. I picked this up from a guy selling FJ40 parts. He picked it up at Spector Off Road like 20 years ago.
- Thread starter
- #7
There are 2 ports at the bottom to drain the tanks as well
If it was mine I would do some inside tank cleaning chemical treatment. Then tape up all the holes and apply some air pressure with a soapy exterior wash looking for bubbles. I'd also make sure the drains work and don't leak after teflon tape treatment. Next I'd look for an ethanol proof liner treatment. Some liner treatment are way better than others do your research!
I had a seam weep back about 85 in my 72. I did the JC Whitney ethanol liner. The inside of the tank looked like new so I didn't do the chemical cleaning. I used some gas tank epoxy to build up the area on the outside of the tank where the pads has caused some pitting from dampness - It was a rag top from 72-80.
I sort of miss my aux tank. It was really handy for the back country where there is no gas station. I would just pull the hose off the carb, plug on my fuel hose extension, flip on the key and fill up my 4 wheeler with the electric fuel pump.
I had a seam weep back about 85 in my 72. I did the JC Whitney ethanol liner. The inside of the tank looked like new so I didn't do the chemical cleaning. I used some gas tank epoxy to build up the area on the outside of the tank where the pads has caused some pitting from dampness - It was a rag top from 72-80.
I sort of miss my aux tank. It was really handy for the back country where there is no gas station. I would just pull the hose off the carb, plug on my fuel hose extension, flip on the key and fill up my 4 wheeler with the electric fuel pump.
I think you would need a breather otherwise you'll have problems with venting.
Are you sure the other port is a fuel pickup? It could be the breather port and the tank is meant to use an in-tank fuel pump. It would be strange to have the pickup in the corner like that.
The two sides would also need to be connected in some way, like maybe through the drain ports, otherwise you'll always have fuel sitting on one side that won't get used.
Are you sure the other port is a fuel pickup? It could be the breather port and the tank is meant to use an in-tank fuel pump. It would be strange to have the pickup in the corner like that.
The two sides would also need to be connected in some way, like maybe through the drain ports, otherwise you'll always have fuel sitting on one side that won't get used.
- Thread starter
- #10
To be honest, I’m not sure.
I think it's a breather port. If it was a fuel pickup, if you unscrew it there would be a long tube extending almost to the bottom of the tank under that port. Normally it would be more centered in the tank, having it in a corner like that would cause problems on every turn when the fuel level gets low.
The more I look at it, I think it might have been used as a transfer tank. You'd fill this tank, and the 2 drain ports were used to gravity feed back to a rear tank. That would explain the lack of pickup, vents, or return ports. But that's just a wild guess.
The more I look at it, I think it might have been used as a transfer tank. You'd fill this tank, and the 2 drain ports were used to gravity feed back to a rear tank. That would explain the lack of pickup, vents, or return ports. But that's just a wild guess.
