Urgent question on fuel tanks?

[89vn]

Hi guys.
Ive had to replace the fuel tank in my vr Berlina 5ltr.
The only tank Ive found at short notice is a tank from a v6 vn.
Im just wondering if i can just simply swap these tanks over? Or will i need to put the fuel sender unit from my old tank in the new tank? Or can i just swap them over and my fuel gauge will work fine?

[Brett_jjj]

The VN and early VP tanks used a seperate fuel return line going into the tank. The later tanks had the return line going into the tank through the fuel sender assembly. The VN 85 litre and 80 litre long range tanks used two seperate fuel pumps, an internal low pressure pump and an external high pressure pump. Im pretty sure all the 63 litre tanks all used similar sender/pump units so they should work no worries.

[89vn]

Yeah mate both tanks are 63ltr tanks.
The old tank only had the one fuel pump inside the tank. And the return line went in through the centre.
The one out of the vn Ive got has the return over to the left of the tank but i think ill just plug it up and put my old sender unit and pump into the new vn tank Ive got.

[Brett_jjj]

That sounds like it should work fine as long as your VR sender assembly fits the older tank,(which is should do).They both look the same when looking at them both in the workshop manual pics.

[wortus]

One problem you might have trying to use the VR sender unit in the VN tank is connecting the fuel return line inside the fuel tank up to the swirl pot. I think this might be quite difficult? What might be easier for you to do is to compare the fuel senders by checking the resistance range of each one from full to empty with a digital multimeter. If they are more or less the same (within manufacturing tolerance of say a few ohms) them there will be no issues with your fuel gauge and you can use the VN sender unit with the VN tank. I just reckon running a longer bit of fuel hose from your return line to the spiggot on the VN fuel tank would be much easier than trying to reconnect a piece of hose inside the fuel tank.
The only other thing you will have to check is the number of breather hoses on the top. VN's (and probably VP's) have 3 where as some later models (not sure if it changed on VR or VS) only have 2. th elast time I replaced a tank the larger breather hose was available from Holden as was the hose that connects the filler neck. The only one NLA is the small diameter breather hose. Check all these hoses and replace where nessecary while it's out.
I'd also consider using your current fuel pump unless you know how old the VN one is as it's an unknown factor and the last thing you want is a fuel pump breaking down, however if both pumps are fairly old you might want to consider a new genuine one as they are only about $100.