Original Challenger locking gas cap differences and questions.

[GrandpaKevin]

Yep real bored.

Previous WIW question on the Challenger locking gas caps got me interested in getting the one I have fixed so it will lock.
I identified the broken internal part and am going about finding or making a replacement.

So will all my free time I searched E-bay for possible parts.
I remember reading these caps were originally made by Briggs and Stratton so I searched for B&S locking gas caps thinking a B&S locking cap might have similar internal parts.
Amazingly I found and purchased an original, unused Challenger locking gas cap being sold from an estate of a family who used to own a Dodge dealership from back in the day.

So the difference between the two (besides condition) is on is marked Non Vented and the other is Pressure Vacuum.

The new one locks and the old doesn't and I understand the issue and the fix.

I know one is for California emissions type fuel systems and one is not but can anyone tell me the actual physical difference between the Non Vented and Pressure Vacuum caps?
Is it the seal?
They look identical but do have slightly different part numbers.


Will the Non Vented cap work on our 71 Challenger that originally came with a Pressure Vacuum one?
The tank and fuel system is stock type but has no factory fuel return system and only a couple vent lines connected.

Thanks.

[JS29]

  That was a good find! 

[Chryco Psycho]

70 was the only year that was vented the others were sealed & vented into the engine breather so as long as the tnak has a vent elsewhere in the system to vent you will be fine .
Briggs & Stratton made all of the locks for Mopars & other as well back in the 70s & 80s
Being a locksmith I would be interested in the vented one that doesn't work .