auxiliary fuel tanks

[ericos_bob]

Have been working on converting my syncro transporter into a long range camper van. Having all kinds of problems installing an auxiliary fuel tank and after looking long and hard for suitable fuel tank location under the car I found the only way to fit a tank under the car without losing any ground clearance is by mounting two tanks between the chassis rails. I can't afford to go that route so bought an 80l slimline poly tank that I'll install inside the van behind the driver (rhd) side of the car.The plan is to cut a hole in the outside of my syncro where the 2wd vanagons have their fuel filler and simply install a used 2wd filler there which will be routed through under the battery tray to the tank. Now the trouble I have is as follows

My tank arrived and everything is upside down That being I need to reverse at least the fuel outlet so it is facing the correct direction. I'm scratching my head trying to workout the best way to cut a hole in the tank and install a brass thread for a fuel line outlet. I have never worked with poly fuel tanks so not sure how to install a fitting. Is there a tap and drill set I can use to make a thread in the poly tank like with a helicoil set or do I just cut a hole in the tank the size of my outlet pipe and melt a piece of pipe into it. Can poly be glued? and what fuel resistant glue would I use or am I better off trying to plastice weld it? Don't want to end up with leaky fuel in my syncro after all. Thanks

[kevtherev]

I'm pretty certain that plastic fuel tanks are extreemly rare here, but Ilegal? I'm not sure about that , though saab did fit one as did some bike manufacturers.
I think five gallon jerry cans look ace on syncros

Away from all that though
can you not simply extend the existing pick up tube at the outlet to reach the bottom of the tank?

[toomanytoys]

Assume diesel??? do you want 80 L of smelly D leaking out into the interior??
Unless the plastic is quite thick making a thread i it is prob not an option.. fitting a "tank flange/bulkhead" type connection (s) would be safer..
It will need supporting really well, 80kgs of liquid sloshing about will make the tank flex quite a lot... really you want to make only 1 hole, big enough to allow a sensible fill rate near the bottom and tap off of that for the transfer to main tank... breather will need routing too....

IMHO a fabricated stainless or Alloy tank would be the way I would have gone.. either between the outer sill and chassis rail (depending on what tanks/heater etc etc mounted there already, like what was available in South Africa) or...
a shaped tank/pair of tanks directly behind both seats with link in the walkthrough, or a low profile one that fits on top of the floor in the main area..
Another option would be in the space where the spare wheel would sit on a 2wd (unless you have the "205 wheel carrier" fitted)

[Plasticman]

Sorry, dont go there it will end in tears or worse, I would make a pair of tanks to fit the space or as said a couple of gerry cans, what range do you want and why?
mike

[ericos_bob]

Too many toys. Forgot to mention I got a petrol engine. It's a diesel grade tank rather and is very thick designed for agricultural and outdoor applications. Plastic is almost a half inch in thickness so I assume that's plenty of meat to make another fuel outlet? The tank has plastic bridges throughout and feels quite solid. Here's a pic for to give a better idea http://www.allstores.com.au/product_ima ... k-bott.jpg
http://www.allstores.com.au/product_ima ... nk-top.jpg

Yeah under floor would have been nicer for sure and those chassis rail tanks are still available in south africa though they hang a little low for my liking. May go that route some time down the track.
Any idea on how you'd go about making another fuel outlet? There are two optional fuel outlets on the tank of present which are plugged. One will become a breather when the tank is flipped upside down.

Sorry, dont go there it will end in tears or worse, I would make a pair of tanks to fit the space or as said a couple of gerry cans, what range do you want and why?
mike

Too late I've already go the tank so I will be going there. I will be doing a lot of the big desert tracks in inland australia. A range of 1500km on road is what I'm aiming for as I can cut that in half in the sand. In the past I carried 4 jerry cans instead but was annoying to fill into the main tank and still not enough fuel to get me by between stops. With the 80l spare plus 2 jerry cans I should be 'OK'.

[toomanytoys]

Speak to the manufacturer....

[Plasticman]

Ok starts to make more sense now with regards the range, plaggy tank looks interesting, as said talk to the folk that make them getting fuel out wont be that big a prob, nor will breathing it, getting it in looks er well where is the hole? also want to make sure you get continuitty of supply so valves etc,
Must admit I once made a 250ltr oblong tank all baffled etc to fit in the back of an old ambulance I had, dont ask why.. and got to s of france and most way back after the alps
good luck with it
mike