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How to install VN-VS long range fuel tank to VL.

Started by TUXEDO · 24 June 2012 · 39 replies

Preserved from CalaisTurbo. Original authors and dates are shown; archived members are not current Holdcom accounts. View original archive ↗

TUXEDOArchived member
I have done a couple of these conversions now and with people frequently asking how it's done, I though I would make a tech thread. Which tank? You can use any tank from VN to VS. Ideally, You want to find yourself a VN V8 tank as they are the biggest (90L) and all have straps to suit live axle. With IRS vehicles, the tank capacity is ~80L and the LH strap is different at one end as can be seen below. IRS on the left, live axle on the right. My latest install, I used an ~80L tank from a VQ Statesman. So I had to modify the LH strap to fit the VL. I did some measurements then cut and shut the end of the original VL strap on to the VQ strap. The filler neck. I have never actually measured the 2nd gen filler neck, just always assumed its longer so I just cut the neck of the VL tank. While its out, I replaced all the breather hoses. Here is a photo of the diagram in the Holden factory workshop manual. Also the main over flow / breather is a lot larger on the 2nd gen tank. So I have pushed a short length of 15mm hose on to the tank, then pushed a length of smaller ~10mm hose inside that and up to the filler neck. (will post pics later) Return hose. Both tanks I have done, have had the return hose to the swirl pot broken off inside the tank. No this is pretty much impossible to fix without cutting the tank open. So I have modified the sender unit to house a return hose directly in to the swirl pot. I forgot to take pics before I did this but I cut the end off this short pipe which is normally crimped at the end. It's a little short so I put some Loc-Tite super glue on it for a bit of added strength to hold the hose on. Then on the other side, I cut a small section of pipe off, clamped a length of hose to it then ran it along the pump bracket and zip tied it in to place. As you can see here, I fitted a new lift pump for peace of mind and I used the original VL sender unit although in most cases, the senders are the same. Other than these few things, it's all pretty straight foreward; remove and replace. I recommend replacing all you old fuel hoses and clamps at the same time. I spent a fair bit of time and money prepping and painting my tank asteroid silver and this was the result. I wrote this article on my iPhone so I'll edit and add to it when I get on my PC lol. Some original photos have not been recovered yet.
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VLWAGONITArchived member
good effort man. also if you are chacing a new cork gasket for the sender, asfar as i know you cant get them for vl's anymore but most places still stock them for vs tanks which fit perfectly. good idea modifying the return line aswell, never acctuly checked one too see if its still there. will do when i take my tank out to paint it Some original photos have not been recovered yet.
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leb vltArchived member
Gd write up. Locky, wouldn't it be better to use hose clamps instead of cable ties, incase of them perishing?
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TUXEDOArchived member
VLWAGONIT: I have just put a new pump in the tank when I have done these conversions and they come with a new gasket. Thanks for Your input. lebvlt: That is a good idea Mo, I will do that before I put it back in. I just figured there is plastic on the pump and strainer, what's the difference? but it probably is a different type of plastic! Cheers. Some original photos have not been recovered yet.
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hillerusArchived member
Excellent write up. Will come in handy for when I do this to mine. Are you just running the one internal pump on this setup now?
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5spdvlArchived member
Re: plastic + fuel, AFAIK it's just poly vinyl chloride (PVC) based plastics that dissolve/soften/weaken in fuel. Good article, looking forward to the rest of the pics. Have you found any difference in bolting patterns between the sender/lift unit/pump and tank? Had an issue a few years ago with a 5 bolt tank and a six bolt sender/pump assembly.
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HTURBOArchived member
Quote: Originally Posted by 5spdvl [View Post] Have you found any difference in bolting patterns between the sender/lift unit/pump and tank? Had an issue a few years ago with a 5 bolt tank and a six bolt sender/pump assembly. I'd like to know aswell. Some original photos have not been recovered yet.
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FLY-03LArchived member
Nice one. I did a drop tank in mine and it was a bit of a **** around. So, there isnt actually any difference between with IRS tank its just the straps? I believe my tank was out of a VR SS, and it had a slip join cut on the filler neck
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TUXEDOArchived member
Yes there are some tanks & senders with 6 bolt flanges. I'm pretty sure the loom plug / wiring is different so is useless for use in a VL. Correct about the tanks being the same between live axle and IRS, it is only the LHS strap that is different. And yes the filler necks are seperate to the tank VN onwards.
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brabusArchived member
i was trying to take mine off to re spray it but for some reason it wont seem to come out i have un bolted everything under neath the car thats connecting it together and it doesn't seem to want to come out
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fleasArchived member
Could be your filler neck hitting and grinding against the right-rear panel (after you've taken off the stone guard)? Give us a rundown on what you've loosened thus far.
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vlturboboArchived member
any idea guys on what i should do with my tank. just recently started building up the old girl (VLCT) and the tank hasnt had fuel in it for 2 - 3 years. im worried theres moisture,water, sediment, etc in there. any ideas guys would be appreciated. cheers.
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fleasArchived member
Best bet would be to remove the internal fuel pump and give it a good flush. I've also heard that some people can fit their hand in the space but I can't see it happening unless someone has small hands/arms. If you don't wanna go through the hustle of lowering the tank; removing the int. pump you can always buy another tank.
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vlturboboArchived member
thanks mate, what should i flush with though? fuel, methylated spirits.....
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fleasArchived member
Methylated spirits AND have also heard of fuel but I'm not entirely sure. Maybe someone can elaborate on it.
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GMHVNArchived member
quick question... can you just use the vn sender from the drop tank or you have to use the vl one?
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TRELL4Archived member
Yeah i used the vn sender i just chucked it on plugged it up and works great! Mine is a 90ltr off a Vn ss
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VL-DanArchived member
I'd like to know that also^ I would have thought the VN sender would be different because the tank is alot deeper?
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GMHVNArchived member
Quote: Originally Posted by TRELL4 [View Post] Yeah i used the vn sender i just chucked it on plugged it up and works great! Mine is a 90ltr off a Vn ss Thanks man just what I was after.
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TRELL4Archived member
Quote: Originally Posted by VL-Dan [View Post] I'd like to know that also^ I would have thought the VN sender would be different because the tank is alot deeper? Im not sure ive had my drop tank in for about a month now in my vl calais with the vn sender and it works no worries the fuel gauge seems like it works okay no issues yet
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