Failed smog test fuel tank not holding vacum

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amoparacer

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So my 76 Feather Duster runs great now. Took it to Smog test fail little to rich had new cat installed old one was empty yes like resonator empty. Crap gas cap test fail tank not holding vacuum . Crawled under car clamped vent hose still does not hold vacuum. So maybe sending unit seal or Filler neck donut. Any one does the vent tub in the tank have a gromet or is it welded in can tell its in the car. Dam Communist Californication Smog test:violent1::violent1::violent1::violent1::violent1::violent1::violent1::violent1:
 
vent tube stub is solid to tank then short rubber line to metal fuel/vent line., Sending unit possible, but would probably leak gas. I would think neck grommet likely if you think the cap is sealing. That should be same as my 75 - vent line is 2 piece with a rubber hose connecting near passenger floor, then up to charcoal canister. Be sure all are attached.
 
Filler cap correct? Is this an "all factory" correct installation, etc?

Here's some photos from my 74 shop manual, which YOU should have one of
 

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Since when does SoCal require smog for a 76? When I lived there my 65 required smog just once when you sold it, and the limits were fairly loose. Did they require you install a catalytic converter or did 76 CA cars come that way? I doubt it since I don't recall even hearing of cat converters until ~1979 when some new Corvettes started grass fires.
 
76 is the first year for smog yes cat was on all california A bodies. Older than 76 not smoged. So in your case Bill your Voyager and TC get smoged every 2 years. Your Diesel cars are exempt your other 135,000 plus also are exempt IE older than 76. There are rumors that governor MoonBeam may be about to exempt all cars older than 79.
 
Since when does SoCal require smog for a 76? When I lived there my 65 required smog just once when you sold it, and the limits were fairly loose. Did they require you install a catalytic converter or did 76 CA cars come that way? I doubt it since I don't recall even hearing of cat converters until ~1979 when some new Corvettes started grass fires.

75 and older is no smog in CA, even in the high pollution districts if i remember. And 76 was the first year for CATS as well...
 
vent tube stub is solid to tank then short rubber line to metal fuel/vent line., Sending unit possible, but would probably leak gas. I would think neck grommet likely if you think the cap is sealing. That should be same as my 75 - vent line is 2 piece with a rubber hose connecting near passenger floor, then up to charcoal canister. Be sure all are attached.

Its the same as your car. I orders a sending unit and Filler neck grommet.
Was funny when cat removed it had no ceramic inside totally hollow.:finga:
 
Retard the crap out of the timing and take it back.
 
Somewhere,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,I still have "that" smog ticket I got in my Navy days............................
 
I brought this up on another thread a while ago - that the new vent lines that are available do not have the valve in them. Would a stuck open or missing overfill valve cause a filler cap/vacuum failure?
 
Did they pressure test the cap itself? I'd check the donut too but when my son's was bad, it weeped fuel around it while driving. It looked moist around the tube and you could smell it a little.

1975 was the first year for cats in California. I took driver's training in the spring of 1975. Our high school's driver training cars were all new 1975 models from a local dealer and they used to fill them with leaded gas from tanks on campus back at the bus barn. What a mess that became and stink! My mom had a '75 Cutlass Supreme and my dad had a '76 Cutlass Supreme and both had cats. Brief interesting history lesson below.

As early as 1953, Los Angeles County Supervisor Kenneth Hahn inquired of Detroit automobile makers as to whether research was being conducted to eliminate emissions. The response was vague. With the threat of mandatory federal regulations, the auto industry began to install crankcase blowby devices (which returned unburned gases to the combustion chambers) on their cars. This was a significant advance because crankcase blowby produced 25 percent of the engine's hydrocarbon emissions. This equipment became mandatory on all cars sold in California beginning with the 1963 models.

This was only a start, since no effort was made to control exhaust emissions that were responsible for 55 percent of the hydrocarbons, most of the waste heat, and all of the carbon monoxide, nitrogen oxides, and lead emissions. Once again the industry balked, but in 1966 California required exhaust-control devices on all new cars. However, the 12 percent drop in hydrocarbon emissions and reduction in carbon monoxide experienced in Los Angeles between 1965 and 1968 was accompanied by a 28 percent rise in nitrogen oxides. By 1968, nitrogen dioxide, which is highly poisonous, exceeded the "adverse" level on 132 days. The serious increases in nitrogen oxides were due to the inability of available antiemissions technology to act on them, as well as to the increase in automobiles and rising gasoline consumption. A new technical fix was sought from the automobile industry and, in response, catalytic exhaust devices were developed to convert nitrogen oxides into harmless by-products. Catalytic converters were required on all 1975 cars sold in California. Leaded gasoline, however, played havoc with the catalysts. One solution was to use lead-free or unleaded gasoline. (Another was the unauthorized removal of the devices by motorists.) While non-leaded gas became available, the complete phase-out of leaded gasoline, as stated earlier, did not commence until 1986.
 
Looking at it 40 years later, most people would say it turned out very well, though the transition was far from smooth (remember how 1979 cars drove?). One can now see the mountains from Huntington Beach many days, when even in the 1990's you were lucky to see them from San Gabriel. Unleaded gas was also good because little tykes didn't lose 10 IQ points from lead in the brain. Cars today are both powerful and economical. It isn't always equitable in CA. SF Bay cars have less stringent regs than us in the Central Valley, yet much of our pollution blows over from there. My biggest gripe is classic car owners who insist on putting in mega-thumper cams that cause their cars to idle like crap and pour out noxious fumes, just because they can. They keep it up and rules will come down to impact all of us.
 
I'd like to know more about this alleged "vacuum test" that failed.
 
I'd like to know more about this alleged "vacuum test" that failed.

Have not dealt with this yet, but PA requires 'visual and gas cap' tests begining with 1975 which is what I have. From what I read... in PA a 'gas cap test' is just that. They put your cap on something that checks the seal. However, I also read that CA 'smog' machine is fitted between the car and the cap to test the system. Would love to here more details on either test from an inspection mechanic...
 
Maybe you could get them to explain it to you? As someone mentioned, the carbon can up front is connected to the vent system. It could be a problem in there I guess. Can't they at least tell you if it's the cap or something "in the car?"

"You guys" in these states that have these incredibly stupid laws need to start getting on your state people. I see NO reason why cars this old should be expected to pass emissions. After all, just how many are "on the road" and just how many are driven substantial amounts of miles? I can drive around in this town for a WEEK and not see a car older than 90's something.

Arizona even has some requirements for 67 vehicles WHICH NEVER HAD any engine emissions except for PCV. And some states require you to "go by the engine year" if you have a newer engine. This could mean that if you've replaced nothing more than the engine block, you suddenly must pass emissions with your older car.

It's all very stupid
 
Up here in Shasta County they pull the cap and put it on a vacuum pump to test the cap. It's different all over CA as Mr. Grissom states.

I avoid the rush and crowds of SoCal these days whenever I can but there really is a huge difference from the '60s-early '80s that I remember. We used to live in Ventura County and after spending a day in the L.A. basin my eyes would be slightly burning and my chest felt like there was pressure pushing in on it. I whine everytime I have to take a car in to get smogged but I know it really is for the best. It has made a difference.

We have a 2012 diesel vehicle at work. It's one of the certified clean idle jobs that requires DEF in it's own little tank. We've put 74k miles on it in the last year and a half and the stainless steel exhaust tips still have the stainless showing on the inside. No soot, just bare metal. I can attest that there's no visable crap coming out of that tailpipe. We'll see in the next couple years if there's anything invisable that's nasty like in the gasoline additive MTBE fiasco.

We're literally at the very northern tip of California's central valley surrounded by mountains on three sides. Our ozone levels usually receive a failing grade in the summer and then the county gets dinged for failing to meet state ambient air quality levels.

"Ross Bell, manager of Shasta County's Air Quality Management District, said the county is at the mercy of the weather and geography when it comes to the number of days it violates the ozone levels.

Low-level ozone is created when sunlight and heat react with emissions from automobiles and other sources such as smokestacks, solvents and paint.

Surrounded by mountains on three sides, Shasta County can be an ozone incubator during the summer as it traps sunlight, heat and pollutants blown up the valley from Sacramento and the Bay Area, Bell said."

Currently the burning off of the harvested rice fields are giving us some smoky days. The price to pay to live in what is otherwise paradise. Oh did I mention that Shasta County is also the whisky tango tweeker capital of the US...that's for another post.
 
Smog test on a 1976 car??? How the heck do you get an old car to pass a smog test? Most of the counties here do not do pollution tests at all and when they do its only for cars like 1996 up..
 
Smog test on a 1976 car??? How the heck do you get an old car to pass a smog test? Most of the counties here do not do pollution tests at all and when they do its only for cars like 1996 up..

When I bought that '74 Satellite in 2003 that my son has now, I had to smog it one time and then the sliding year scale caught up to it and I never had to smog it again. On that car they put the probe in the exhaust and read that. It had to pass a lesser stringent set of numbers than late model cars. Then he did an underhood visual to make sure everything was present. It failed the first time because even though all the emission controls were there, when he revved the engine, the EGR valve didn't respond.

The guy was cool and let me copy the pages out of his emission manual that pertained to it. I found that the short-lived timer on the firewall who's purpose blocked EGR function just after engine start-up wasn't working. I used a tee in the vacuum lines to bypass it but it was still present and the EGR worked perfect with the required engine rev. Brought it back for the retest and it all passed. Funny thing is that it passed the emission test the first time around. It was the visual that failed it.
 
Okay so the canister is good all new hose. They clamp off the vent tub before the metal line running back to the tank. Then they test your cap at the machine. Then they crew a cap on you filler neck and apply vacuum. It failed the filler neck test. On the way back home I noticed gas smell inside the car. Also in the drive way outside you can smell it now. So once the grommet for the filler neck and my new stainless sending unit are installed should be good now. So I conclude that the vacuum finished off sending unit gasket or tank doughnut. Before the test i had no gas smell at all.
 
Up here in Shasta County they pull the cap and put it on a vacuum pump to test the cap. It's different all over CA as Mr. Grissom states.

I avoid the rush and crowds of SoCal these days whenever I can but there really is a huge difference from the '60s-early '80s that I remember. We used to live in Ventura County and after spending a day in the L.A. basin my eyes would be slightly burning and my chest felt like there was pressure pushing in on it. I whine everytime I have to take a car in to get smogged but I know it really is for the best. It has made a difference.

We have a 2012 diesel vehicle at work. It's one of the certified clean idle jobs that requires DEF in it's own little tank. We've put 74k miles on it in the last year and a half and the stainless steel exhaust tips still have the stainless showing on the inside. No soot, just bare metal. I can attest that there's no visable crap coming out of that tailpipe. We'll see in the next couple years if there's anything invisable that's nasty like in the gasoline additive MTBE fiasco.

We're literally at the very northern tip of California's central valley surrounded by mountains on three sides. Our ozone levels usually receive a failing grade in the summer and then the county gets dinged for failing to meet state ambient air quality levels.

"Ross Bell, manager of Shasta County's Air Quality Management District, said the county is at the mercy of the weather and geography when it comes to the number of days it violates the ozone levels.

Low-level ozone is created when sunlight and heat react with emissions from automobiles and other sources such as smokestacks, solvents and paint.

Surrounded by mountains on three sides, Shasta County can be an ozone incubator during the summer as it traps sunlight, heat and pollutants blown up the valley from Sacramento and the Bay Area, Bell said."

Currently the burning off of the harvested rice fields are giving us some smoky days. The price to pay to live in what is otherwise paradise. Oh did I mention that Shasta County is also the whisky tango tweeker capital of the US...that's for another post.


DEF might be okay where it doesn't get cold, but here it just plain sucks; once it messes up the whole system needs replaced, or just put a tuner on it and be rid of it!

luckily the new dodge trucks meet emissions laws without that crap
 
So I conclude that the vacuum finished off sending unit gasket or tank doughnut. Before the test i had no gas smell at all.

Possibility. I'd fill the tank clear full and let it set in a cool area for 1/2 day or so and then look around under there for 'wet spots'. It's always possible something rusted through, and finally failed.
 
Makes sense, vacuum can definitely open up a leak where pressure did not. It's pushing the seal surface from other direction, plus how strong of a vac are they pulling? What hg does cap normally open at vs what they sucked it down to? old hard seals not likely to reseat.
Okay so the canister is good all new hose. They clamp off the vent tub before the metal line running back to the tank. Then they test your cap at the machine. Then they crew a cap on you filler neck and apply vacuum. It failed the filler neck test. On the way back home I noticed gas smell inside the car. Also in the drive way outside you can smell it now. So once the grommet for the filler neck and my new stainless sending unit are installed should be good now. So I conclude that the vacuum finished off sending unit gasket or tank doughnut. Before the test i had no gas smell at all.
 
Do this (actually if it smells that bad you probably don't need to wait). I would not touch the sender if you don't find a problem. I've seen a bunch of guys posting that new senders not working and either gasket or ring are undersized causing leaks.
Possibility. I'd fill the tank clear full and let it set in a cool area for 1/2 day or so and then look around under there for 'wet spots'. It's always possible something rusted through, and finally failed.
 
Okay so here is the low down. Removed OLD sender no filter no float really crappy. Installed NEW stainless one with gasket the new hold down ring would not hold sending unit firmly installed old hold down ring works perfect. Installed new stainless ground clamp it also was broken on car. Installed new vent hose and clamp. Installed new fuel line. So started car fuel gauge not working but moved on to filer neck grommet will trouble shout tuesday after smog check retest. Oh sending unit I removed was very cracked not leaking fuel but not air tight.
 

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