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Classic Cars @ AZT Update

A little petrol story


May 2021


Dear classic car friends,


We have some news about our BMW 318.

We deliberately bought this car in good condition to avoid having to deal with further restoration work, besides the Mercedes.


Unfortunately, even supposedly very good classic cars are not safe from (bad) surprises:


Originally, we wanted to fill up the BMW briefly on a Friday afternoon before the weekend. Back at the AZT workshop, we noticed a strong smell of gasoline and a small pool of gasoline formed under the BMW. On the lifting platform we have checked the car.

The source of the gasoline loss was quickly identified, it dripped down the fuel tank. On this vehicle the tank is still made of sheet steel, so we suspected something bad.


Fuel smell and loss is not uncommon with this model, it is reported more often of such defects in the BMW E21. The cause is often leaky, porous fuel lines, which are installed on the top of the tank, which is not visible from below. A "tip giver" has even recommended to simply not fill up the tank, otherwise leave everything as it is. This was not an option for us as we wanted to get to the bottom of it. After removing the rear seat and removing the corresponding assembly cover, we could already locate a leak:


Here, the ventilation line is obviously torn, but the other visible hoses no longer make a good impression either.

To finally get to the bottom of the leak, the fuel tank was completely emptied with a special tank pump, collected and then the tank was removed.


The traces of the leaking gasoline are very visible here. The disconnected hose at the bottom right is already a new part leading to the fuel tank nozzle. The old hose mounted there presented itself to us in a very porous condition:


So we were lucky, the cause of the fuel loss was not the tank, which only with luck would still be available as a spare part but "only" a few hoses and lines. We were able to replace these quite quickly and the tank is now tight again.


Because we could nevertheless determine some large and a few stronger punctual rust spots on the removed tank, we decided to have the tank sandblasted in order to weld it afterwards if necessary and then to paint it again...


Conclusion: Life with a classic car is never boring ;-)


We will keep you updated



More on the topic:

Article about the purchase of the BMW 318, year of construction 1975

Article about the purchase of the Mercedes 240D, year of construction 1981