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fuel tank question

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H

HarryL

Jedi Trainee
Offline
On my ongoing restoration of the 4a; I
noticed that the fuel tank does Not have
an overflow/air vent. Is this
something I need to address before placing
it back in the car? Was thinking of putting
a brass fitting and running a hose down to the
frame/body.
Harry
 
Well, I can tell you I topped up my tank one cold day before storing the car for the winter and discovered gas poured out the filler cap on an exceptionally warm day from expansion. Damaged the paint some but glad the tank didn't rupture from the pressure.
 
ISTR that on a 4A, the cap is vented, no separate vent on tank.

So if turn the car over, run.
 
The vent on the tank (as found on earlier TRs) can dump liquid fuel on the road in hard turns. So I would suggest verifying that the cap is vented (small hole through the inner plate of the cap) and not filling the tank above the bottom of the fill pipe.
 
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