Buying new hose to replace the old, and need to know if it is 5/16 or 3/8. this is the hose from the tank to the main pump

You want 400mm of 1312257 which is 12mm fuel hose. 12mm is .028" short of 1/2". If you cannot find metric fuel hose then just get yourself a yard (meter) of 1/2" fuel hose and you should be OK.

Mark

400mm = 16"
1 meter = 39"
1 yard = 36"

I think all of those sizes is too short to go from the fuel tank to the main pump. Better get about 10Ft to be sure of having enough. Be sure to specify hose suitable for fuel.
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David Hunter

While 400mm is about 16" it is still exactly what the parts fische in Vadis calls for. You can buy 10' of fuel line if you want but be ready to have about 7+ feet left over. While I always run factory Volvo stuff, whether it is my car or a customers, I am sure you could find a less expensive substitute. The factory hose is $29.69 per meter! $30.00 to rehose your car is a little steep, $100.00 to make sure you have enough is rediculous. If you look up an earlier model car in Vadis it will show you that it takes 900mm of the same line, this equals 35.43". Buy yourself a full meter of it (make sure some chucklehead behind the counter does not give you what he THINKS is a meter, unless he gives you extra) and be done with it.


Mark