911 Fuel Tank Repair

[OzPete]

Hi All

My first post and first Porsche (1973.5 911 T). I have a problem with a punctured fuel tank and I was advised best to replace it. The new Dansk tank has three screw fittings (two upper 22mm and one lower 14mm) whereas my original had two push on metal tubes (about 8mm & 10mm OD) and a 22mm drain plug plus a screw in fuel filter in the base. The Dansk tank has no internal slosh prevention structure nor the base fuel filter.
I have been able to source 22mm threaded joints (with filters attached) that I think have 6mm & 8mm pipes and also screw plugs in 14mm and 22mm. But Porsche UK & Design 911 no longer stock the 14mm Ring Piece/Banjo Bolt assembly for the return fuel line into the tank. My options as i see them:

1. Cap the 14mm lower/smaller threaded inlet with a screw plug & washer and attach the return to another 22mm Threaded Joint in the second upper threaded inlet.

2. Drill & weld a pipe through the 14mm screw plug and attach return hose to that. Plug second 22mm threaded inlet.

3. Start again and get the puncture (5mm wide by 50mm long on centre of the leading edge of the tank) welded? I have read this is not advisable but not sure why.

4. Does anyone know where I can source the 14mm ring piece (Part No> 901 356 049 00)?

Final Question - how necessary is the anti-slosh structure - clearly the reason the Dansk tank was a lot cheaper than an original tank?

Thanks OzPete

[Nick Moss]

You would have found the whole fitting process easier by using the 85L tank, designed for CIS engines. The banjo is available from places like Think Automotive, who specialise in pipe fittings

[fetuhoe]

The biggest issue seems to be that the filter is not compatible and there is no lid on the plenum.

[OzPete]

Nick

Thanks - I was considering a 85L tank but read in several places that it was only for either 07/73 onwards cars or 1974 onwards cars , so seeing mine is an 04/73 CIS I went for the 65L tank. What are the fitting differences between the two, other than the tank is larger/higher?

I am also puzzled by the lack of plenum in the Dansk tank. When ordering thru Design911 they offered on line the Dansk (without internal baffle) for £155 or Porsche Original for £1250 - no mention of a Dansk tank with a plenum/baffle. Does anyone have a negative experience with a Dansk type tank without a plenum ?

Thanks OzPete

[hot66]

85l plastic tank was available for lhd 72/73 mfi cars

[fetuhoe]

The photograph I posted showing the 85 litre tank is the current Dansk tank which is sold 'without plenum'

[Alan @ CanfordClassics]

In case it helps, the 73.5 tank is unique to that model. Most just fit the Dansk 85 ltr tank but it is not 100% correct for your car. Back at the workshop on Monday if pics help as I have one type of each on the shelf.

HTH

Alan

[OzPete]

Alan

Many thanks I would be interested to see the pictures. I also noticed on your site that you have re-manufactured the fuel return banjo fitting - does it included the bolt as well as the ring piece ? I assume the bolt is a 14mm thread ?

Best OzPete

[Alan @ CanfordClassics]

Hello Pete, we do indeed make those return banjos (which does have the bolt fixing) but I think we need to make some more as that shelf was empty the other day. I will grab some pics for you tomorrow.

Happy to help if we can

Alan