Ponty

Hi all

My 81 has just developed a leak, at the usual spot near the bottom bracket. Just discovered this after I filled it to the top! Once I find enough containers, I plan on draining and removing the tank. I've read lots of old posts and most suggest replacement, which appears to be $1,150 plus freight to Australia.

So, is there currently any recommended glues for Polyethlene? Given;

a. I'm desperate, my wife's daily driver (a Lexus LS400 - great car) is getting hail damage repaired, so she's pinched my other vehicle, meaning I need the 928 asap.

b. I can't really afford a new tank

thank you
Jim

vanster

I am facing the same issue. It leaked in the past and I stopped it with DS11 which is made for stopping small leaks that are water or fuel related. I found this at Grainger
which I know are in China so must be available down under
Also check with a marine supply store. they might have something for you.

jpitman2

pc11 worked for me at the outlet threaded insert, but it dries pretty hard, so I doubt it would flex miuch without breaking.
jp 83 Euro S AT 54k

bradartigue

I recently did the same thing; I removed the tank, scuffed the surface around the strainer with fairly coarse sandpaper; cleaned the area with acetone; scuffed some more; cleaned some more; sealed with JB-Weld. Once dry I sealed over the JB-Weld with an oil and gas resistant epoxy. JB-Weld is also oil and gas resistant. Sealed up fine. Long term unknown but I couldn't afford to buy a fuel tank right now either.

brutus

The J B weld is just a temporary patch since nothing sticks to the plastic tank well at all.

Ponty

thanks guys, I'll take a look for those.

I'm not confident I can make it work but I might as well give it the best shot I can as a new tank would be 1/5 of the cost of my car!

ps - why does this happen when

a. your car has a full tank
b. everything else in my garage (ride-on, quad, edgers etc) all have near full tanks too.
c. you don't quite own enough fuel containers!

cheers

bradartigue

The multiple cleanings with acetone and scouring with sandpaper and/or steel wool give the epoxy something to "bite" into. If you just try to apply it to that plastic it will chip right off as you describe. I couldn't chisel this stuff off now if I tried - and I was so frustrated with my first attempt is why I probably overdid it with the scouring and multiple epoxies.

928mac

I had mine apart 3 times and I found that it was leaking from the electrical connectors for the in-tank pump. I used a air line to blow it dry and get a good look, then I saw where the leak was coming from.
If you dont have an in-tank pump you dont need to worry.

danglerb

Somebody on Pelican was fixing one with something called marine fuel tank sealer or something like that.

Ponty

I didn't have much choice at my small auto accessory place and ended up buying a 2 part epoxy plast tank repair by Specialty...

A big thanks to Dwayne for his instructions on how to remove a tank - they were great!! So good I had to duck into work to print them all off. My only variation, I ended up making a 6mm allen key bit to fit my rattle gun as I couldn't get the allen key bolt at the gas filller to budge. My tank is stamped July 1980 so I assume it's an original (my car is an 81).

Oh, and I casually I tried to fit 6 litres of fuel into what turned out to be a 5 litre quad rider tank...

Jim

jon928se

Pieces from a HDPE chopping board ($1 or so from IKEA) "welded" into place with a soldering iron and judicious use of a hot air gun fixed the crack in my 90GT tank.

heinrich

I sincerely hope that when you guys sell these repaired cars, you expose this fact to a potential buyer. For me, I would replace any cracked or repaired fuel tank. Used ones are cheap.

awdmoke

Used ones are not cheap, nor available in Australia.
I cracked my tank, and had it professionally welded by a HDPE fabrication company here in Perth.

heinrich

Sorry... agreed, outside the US and EU, parts are very spendy.

Ponty

Well, so far so good..

I pulled the tank out and repaired it with the two-part epoxy and left it overnight. Filled it with water and no leaks.

So I re-installed the tank and half filled it (well, 40 litres worth) and surprisingly, no leaks. Despite removing the tank and having water in it, the car started straight away and didn't miss a beat! I love the way it does that.

So far I've done a 10 minute drive and no leaks yet. I'll drive to work tomorrow (only a 12 minute country drive) so that will be the next test. I think if it does fail I might try and find a plastics person for a more professional repair (as mentioned above) or else buy another tank.

Incidentally, I have a cattle grid at the entrance to our property so I'm sure that can't be good for a tank!

Jim