Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum - View Single Post - Can anyone confirm HDPE is fuel tank material

Kingtal0n · 03-01-2021, 08:23 PM

Oh cool!! thank you

So, how do we interpret this data, The outside of the tank is HDPE but the middle and inner layers are PAG (Woven glass fiber in polymer materials?)
I contacted a big plastic welding company and they said The tank has Fibers in it and can't be welded! So they must be talking about the PAG

This is the patch I found which claims to bond completely for a permanent HDPE fuel tank seal,

https://tbbonding.com/repair-a-gas-tank/

Right now plan is buy a 2nd tank, and reinforce it using that patch kit. Then swap out the fuel tanks, and repair/patch the original as a spare I guess
Hopefully will wind up with a bullet proof fuel tank. I'll replace the rubber strap materials so its nice and softly nestled.
I was thinking of melting some HDPE welding rod into the problem areas... debating
Will def pressure test before and after. I wonder how many PSI is reasonable? Maybe 3-4 psi max?

Only thing I need to know now is what areas of the fuel tank need reinforcement. The pics showing the traditional crack spot are down, anyone got good pics of the passenger side crack that forms? Pretty sure thats where mine is.
But I'd also like to reinforce the seams... where I've seen people use soldering irons to cure pin holes.

I drove yesterday round trip with leaking tank 200 miles and also ~20x 400-500rwhp wot runs near 100mph on one full tank of fuel, its down to 1/8 tank now and parked it up. Before you say "that was dumb" I didn't realize the tank was leaking until after the fun. I took the car out to the middle of nowhere and did a bunch of 0-120mph stuff because I planned to hit the 1/4 track next week. One of the roads was ALLL torn up, huge holes, the car bounced and slammed around at 10mph for a hundred feet, I believe that is what stressed the crack in the tank. In retrospect I believe there was already a tiny crack formed before all this because I would smell fuel for no reason on and off for years. So I think I just made the existing tiny crack larger.

Always knew this day would come. Just happy 240s dont go up in flames over this flaw. That exhaust had to be hot enough to light paper on fire.

03-01-2021, 08:23 PM	#3
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,828 Trader Rating: (17)	Oh cool!! thank you So, how do we interpret this data, The outside of the tank is HDPE but the middle and inner layers are PAG (Woven glass fiber in polymer materials?) I contacted a big plastic welding company and they said The tank has Fibers in it and can't be welded! So they must be talking about the PAG This is the patch I found which claims to bond completely for a permanent HDPE fuel tank seal, https://tbbonding.com/repair-a-gas-tank/ Right now plan is buy a 2nd tank, and reinforce it using that patch kit. Then swap out the fuel tanks, and repair/patch the original as a spare I guess Hopefully will wind up with a bullet proof fuel tank. I'll replace the rubber strap materials so its nice and softly nestled. I was thinking of melting some HDPE welding rod into the problem areas... debating Will def pressure test before and after. I wonder how many PSI is reasonable? Maybe 3-4 psi max? Only thing I need to know now is what areas of the fuel tank need reinforcement. The pics showing the traditional crack spot are down, anyone got good pics of the passenger side crack that forms? Pretty sure thats where mine is. But I'd also like to reinforce the seams... where I've seen people use soldering irons to cure pin holes. I drove yesterday round trip with leaking tank 200 miles and also ~20x 400-500rwhp wot runs near 100mph on one full tank of fuel, its down to 1/8 tank now and parked it up. Before you say "that was dumb" I didn't realize the tank was leaking until after the fun. I took the car out to the middle of nowhere and did a bunch of 0-120mph stuff because I planned to hit the 1/4 track next week. One of the roads was ALLL torn up, huge holes, the car bounced and slammed around at 10mph for a hundred feet, I believe that is what stressed the crack in the tank. In retrospect I believe there was already a tiny crack formed before all this because I would smell fuel for no reason on and off for years. So I think I just made the existing tiny crack larger. Always knew this day would come. Just happy 240s dont go up in flames over this flaw. That exhaust had to be hot enough to light paper on fire.