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Parts, Repair

Great Balls of Fire

Well, not yet, but if I don’t do something soon…

Those of you that have been with me from the start will know that I have had some fuel tank problem… the one in the car was rusty and leaked. I bought a replacement and it was wrong. I had another tank from a 924 S fitted, and that leaked. The wrong one I bought was fitted with some modification to the fuel lines.

Since I’ve been using the car there has been a petrol smell i the cabin, some times more noticeable than others. I just thought it was one of those things, you know, part of owning an old car. But I got passenger complaints and wondered if I’d just got used to it, so I did a little research. Some 924 and 944 owners were reporting that they had found hairline cracks in the top of the tank causing it to leak when filled. So I decided I needed to do 2 things:

  1. Buy another tank to fit, hopefully the right one this time.
  2. Refurb the replacement tank to eliminate any chance of cracks.

I have the replacement tank and sealer, but that’s for another report.

The other evening I decided to get a better look at the fuel lines and breather system for the tank fitted at the moment, to make sure there weren’t any split hoses. I stripped out rear to expose the filler system and top corner of the tank, as seen below.

Porsche 924 Fuel Filler

Porsche 924 Fuel Filler

I then went to the petrol station and brimmed the tank. Sure enough, there was smell of petrol straight away. I couldn’t see anything obvious so I paid up and drove home.

As an aside, to any 924 / 944 owners, have you ever driven without the rear carpet? It’s noisy, but fun – you can hear everything that’s going through the transaxel, the whine from the gearbox under load and the clunk as the gears slot home. Go on, give it a go.

When I got the car back in the garage I went round the fuel hoses, up to the expansion tank and down to where they connect to the tank. Shown left is the main fuel filler which connects to the top of the fuel tank itself. All dry there. The hoses connecting to the filler also appeared to be in good order.

I then followed the pipes down under the boot floor and that’s where I found the source of the petrol smell, just under the floor the top of the tank was damp to the touch. To compound things there is a section of foam, seen in the left photo below, that appears to have soaked up the petrol, with little ventilation to dry out.

Initially I assumed that I had the aforementioned hairline cracks in the roof of the tank. But it turned out to be a little worse than that. The photos below are of the replacement fuel tank.

Porsche 924 Fuel TankPorsche 924 Fuel Tank Filler

The diagram below shows where the hoses should go, the one from the centre of the filler pipe (coming connector pointing down – hose 22) should attach to the tank next to the filler spout (seen above right). Why on earth it goes nowhere, I really don’t know? The tank refurb is going well, in the mean time I need to block up the pipe that has nothing attached to it, and clamp of that hose too, until I can get the new tank on.

Porsche 924 Fuel System Exploded



  1. Pingback: “Petrol”-head No More « #Project924 - September 27, 2012

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