Gas tank pressure - air rushes out when the the gas cap is unscrewed

[MikeB]

I really like the evap system. No gasoline smells in the garage! On my 82 the vent line ran from the tank to the canister, as usual, but then just vented to atmosphere, because I didn't have a purge valve or carb designed to work with it. Still had no gasoline smells because the path to atmosphere was thru the canister's charcoal.

Have to figure out how to do the same with my 69 with it's vented cap.

 

[Raider L]

@HotRodPC,

Yep, three. When I was rebuilding my truck I chunked the stock cannister but then I found out you could get new filters for it. I had to find another one but I didn't want a stock cannister. Instead I came across a Mazda RX7 in my local wreaking yard and it had the hood off. And right out in the open on top of the engine was a nice heavy looking vapor cannister. I got it and installed it on my truck. Mine does have a metal line coming up to where the stock cannister would have been, and installed it.

You must be registered for see images attach

The rubber hose goes to the steel line. That little white plastic cap covers the port that would go to the carb. I called Mazda and asked them about changing any "filter" and they said it doesn't have one, the unit is permanent. Hum.