Non venting locking fuel cap

[David Horsnell]

I've fitted a locking flange under my Monza fuel cap but the locking cap does not seem to be venting the tank, resulting in a massive build up of pressure in this hot weather, and vacuum after a long run on a cooler day.

Does anyone know of a way to vent the locking cap ? or as a last resort te tank itself. It's a Sumo and I dont want to take the tank out again.

Any help would be most appreciated

David
:}

[StuartH]

This was the case with my AK with flush fit aero fillers.
Fortunately I realised that this would be a problem for filling (no wheer for the air to go when the fuel goes in, for running, bit of a vaccuum bulding up when the fuel's sucked out, and for building up pressure as you say.
Unfortunatey I didn't think about it until the car was all put together -doh!!
So I got Ken at AK to make me up a bit of stainless tube to go into the filler pipe (between the tank and filler) with a small stanless pipe welded to it to go to a vent valve (you MUST have one of these - stops all your petrol falling out if you turn over) and out (which being Ken he did for free!! ).
Since then I think all AK's have a vent valve actually on the tank as AK had not done many with this sort of sealed up filler cap before then.


stuart