Lra aux fuel tank installation – page 11 – toyota fj cruiser forum

I’ve run 5 full tanks through the aux tank while traveling ~2300 miles. She has sat overnight with the tanks in various states of fill level with one 4 day period where both tanks were around 1/4 full. No codes have appeared. The controller switch and pump are working fine except for one instance noted below, but I don’t think that was due to any issue with the pump.

*The only issue I’ve had so far is an instance when the fuel transfer rate became unreasonably slow. I had been driving steady for several hours and both the main tank and aux tank were around 1/4 full. I turned the pump on and heard it come on and prime itself (starts out loud and then gets quieter) and continued to hear it run over the next 25 minutes. It should have easily emptied the aux tank during this time and brought the main tank up to around 1/2 full.


However, the main tank just continued to get lower until the low level light came on. So I pulled over to get fuel and investigate the pump. When I turned on the pump after I stopped, it worked just fine and emptied what was left in the aux tank in less than 10 mins. I had however, opened the gas cap by this time. I’m guessing this was a case of vapor lock, but not sure why it happened and it has not repeated itself.

The only issue I’ve had so far is an instance when the fuel transfer rate became unreasonably slow. I had been driving steady for several hours and both the main tank and aux tank were around 1/4 full. I turned the pump on and heard it come on and prime itself (starts out loud and then gets quieter) and continued to hear it run over the next 25 minutes. It should have easily emptied the aux tank during this time and brought the main tank up to around 1/2 full. However, the main tank just continued to get lower until the low level light came on. So I pulled over to get fuel and investigate the pump. When I turned on the pump after I stopped, it worked just fine and emptied what was left in the aux tank in less than 10 mins. I had however, opened the gas cap by this time. I’m guessing this was a case of vapor lock, but not sure why it happened and it has not repeated itself.

That’s interesting. I have seen that with my tank as well, recently in fact. Just returned from Southern Utah and this happened. Initiated transfer. The pump was running. Not much in the way of transfer happening though. We were driving an offroad loop. I decided to leave it running and see what happened. About 20 minutes in the stock gauge went from 1/2 to Full. On the trip home I tried to transfer fuel again. Same thing. Pump running, but no transfer happening after at least an hour of running. Given my history with pumps going bad I decided to change out the pump (perhaps it was running but not actually pumping). In the garage, it’s working fine now. The question of vapor lock is interesting. Perhaps we should inquire about this with LRA? Popping the gas cap is an interesting idea as it could potentially decompress any pressure in the filler neck that could be causing this. I am thinking about testing out a "Super Siphon" to see if it works as a backup transfer system. I hate the idea of being stuck somewhere with 30 gallons of fuel that you can’t access. Even if it is a pump problem, I would much rather change the pump in my garage than in the field.