1979 Dodge B200 360 engine big plastic fuel tank (36 gal)

Went for Ca smog test and was introduced to a new element never encountered before.
Evap system pressure test.
They screwed a cap onto the fuel filler and pressure tested the fuel tank and evap system (charcoal filters lines etc.)
They failed the van saying there was a gross leak somewhere in the system.
All lines depicted on schematic under hood are connected with no breaks or cracks.
It is a 2 cannister system, one cannister has a filter element at the bottom so looks to me like there is no way it could be sealed for a pressure test. Also there is a port at the bottom of the other cannister that is open to air. Does not show on the smog system diagram under hood.
Plugged the port on cannister #2 and changed cannister #1 to a sealed unit (although the original is a matching oem # to the vehicle Failed again.. Getting a smoke test tomorrow to find leak points. (bet it is at the top of the fuel tank ?)
Ques #1 Cannister with filter element at bottom normal ?
Ques #2 what would the extra port on bottom of Cannister #2 be for ?

 

Thought about this evap system pressure test all night.
The canisters have been there since van was new. The one with the filter on the bottom was replaced once with an exact oem replacement part when the filter material broke and charcoal ran out the bottom. That tells me that it is an open or vented system so I am thinking that the test itself can not be done.
So before I make a lot of work and expense I thought I might try asking a calif air resource board referee station or carb themselves.

 

my 84 pontiac had a cannister like yours..filter in the bottom. its a crazy test. all evap systems are open during operation and most are open all the time/ are only sealed for leak testing. Can't see how this test can be applied for a system that never is sealed. systems that old never had to meet leak requirements. You need get more info cause it makes no sense that this is applied to a 79

 

Thank you primem.
Figured it out.
The open canister is normal, When they did the test they clamped the wrong line AFTER the canister. The line that they did not clamp and should have runs from fuel tank to 1st canister and is supposed to be clamped BEFORE the canister.
Actually the test does not need to be run at all on my vehicle because the line from my fuel tank to canister is metal with a very short piece of hose at each end so can not be clamped at all. That is the reason I never saw the test run before ! LOL
Passed smog with flying colors.

 

I am just surprised that California still wants to smog test a 40 year old vehicle.......

 

Hey You:
In the beginning they were rolling the smog test so every year the cut off moved up 1 year.
When the van was about 2 years to exempt they stopped rolling and set the year at pre 1976. So up to 1975 is exempt.
They have also tightened the standards since then as well.
They now send me a letter every year offering a buyout of $1000. to turn it in to be destroyed. (probably a gift card toward an electric ).

 

what every other emission testing province/state has found for post 1996; if all the monitors run and pass...the vehicle will pass it tailpipe requirements. Tailpipe testing is not needed. evap testing isn't needed...modern vehicles test themselves.

 

I am glad I live in Florida.

 

Im glad you figured it out! I thought the evap was an open system!!!

 

they are open...they are only sealed for leak testing.
they are allowed to breather thru the cannister...fuel vapours won't escape the cannister charcoal pellets. they don't want it leaking any where else in the system.