Vapor Canister Delete. No Emissions Test

[1985GMC]

Anything older than 25 years is CT Emissions Exempt. I'm a certified CT emissions inspector, My 85 GMC is exempt. My GMC has a 350 carbureted, with two 20 gallon tanks. My vapor canister currently has only fuel tank line hooked up to it. I deleted EGR, Pollution Pump, Plugged exhaust manifolds and carburetor.

So what's the deal. Can I put a valve cover breather on the fuel tank line? Basically how can I get rid of this vapor canister that is currently doing absolutely nothing?

[Just call me Sean]

It does something. It keeps the truck from smelling like gas and burns the fuel vapors. I would think an emissions inspector would know that.

[1985GMC]

It does something... It does nothing. I have it completely uninstalled. I have no catalytic converters. As an emissions inspector all it did was reburn exhaust fumes.

I'm asking what have people done when deleting the canister.

[86454k30]

I took an axle vent and put it in the line that came from the fuel tank. I have done it on a few trucks with no issue.

[donandal]

I have seen variations of this topic on other forums. I personally choose to keep all the emissions intact for the year of the engine in my build vehicles.

Six years ago i built a custom roadster with a 2008 Subaru engine and drive train. New York said because it was CUSTOM built it would also be emissions exempt. I kept it all anyway.

They were right for six years. They never checked my emissions. This year they said no, It needs emissions check.

I'm glad I had it all hooked up. I just plugged in the OBD and it passed.

I think there are also Federal rules about disconnecting emissions that apply even if the state says OK. Plus, I might want to sell it or move it out of state.

then what?

[Just call me Sean]

Originally Posted by 1985GMC

It does something... It does nothing. I have it completely uninstalled. I have no catalytic converters. As an emissions inspector all it did was reburn exhaust fumes.

I'm asking what have people done when deleting the canister.

You have got to be the worst emissions inspector out there. No exhaust goes through it, you're thinking of the EGR. It holds the gas fumes until the engine can burn them. There is absolutely no reason to delete it.

[donut]

Axle vent. The OP has already ripped everything out.

[franken]

Originally Posted by Just call me Sean

You have got to be the worst emissions inspector out there. No exhaust goes through it, you're thinking of the EGR. It holds the gas fumes until the engine can burn them. There is absolutely no reason to delete it.

Yep. It just stops venting tank fumes. No performance hit.
Its also federally mandated smog equipment. That means its illegal to remove. Of course its unlikely many get nabbed for it.

[Just call me Sean]

Originally Posted by franken

Yep. It just stops venting tank fumes. No performance hit.

Not quite true. They may be just fumes but it is gas fumes. Fuel mileage will go down, so slightly one wouldn't notice but down it will go.

[tucsonjwt]

3/4 ton pickups were exempt from vapor canister requirement, at least in most states, so my C20s all had just a differential one way vent on a short piece of fuel line hose on the third nipple on the sending unit on top of the fuel tank. This does cause a gas odor to enter the cab, so I bought 25' of fuel line and ran it from the third nipples of both sending units on the dual tanks to the rear of the truck to terminate above the spare tire. There is gas odor at the rear of the truck but I am not back there often. Another poster ran that vent line to the air cleaner and burned up the vapors that way.

[Keith Seymore]

Originally Posted by 86454k30

I took an axle vent and put it in the line that came from the fuel tank. I have done it on a few trucks with no issue.

This.

That is also the production setup on my '74 Chevelle, and '65 GTO.

K

[Axle]

Originally Posted by 1985GMC

Anything older than 25 years is CT Emissions Exempt. I'm a certified CT emissions inspector, My 85 GMC is exempt. My GMC has a 350 carbureted, with two 20 gallon tanks. My vapor canister currently has only fuel tank line hooked up to it. I deleted EGR, Pollution Pump, Plugged exhaust manifolds and carburetor.

I'm not quite sure what I should write in response to that...

-

Stick an inline fuel filter on the end of the line. Lets it breathe, keeps the bugs out.

Alex.

[kalbert]

Here's what the parts you have unhooked really do:

Vapor Canister: collects vapors off the gas tank and sometimes carburetor bowl and stores them instead of releasing them into the atmosphere. Those vapors are stored and in certain driving conditions are drawn into the engine to be used. Immeasurable impact on economy, zero impact on performance. It's actually a really great way to vent the fuel system.

EGR Valve: Recycles exhaust gasses back into the combustion chamber to lower combustion temperature. The exhaust gas is nearly inert and is recycled into the chamber to take up space. Only operates in certain driving conditions, a properly operating system is undetectable.

Air Injection Pump: There are two ways this can work. One system injects clean air into the exhaust right as it comes off the port. The sudden presence of oxygen in the super hot exhaust gas causes remaining partially burned hydrocarbons to finish burning up rather than be emitted into the atmosphere. The second way is to provide fresh air to a two stage catalytic converter. The second stage of the converter requires oxygen to complete the reaction, without it the second stage often will melt down into a solid lump. Either or both types may have been present depending on your sticker. Only operates in certain driving conditions. Performance loss is minimal, ~5hp to drive the pump.

Catalytic Converters: Contain a catalyst that promotes rapid conversion of hydrocarbons and noxious gasses into less awful gasses. Often blamed to be a performance problem, but in reality only the old bean type were hogs. Modern honeycomb style converters are as high flowing as pipe. To work properly it may require fresh air via the air pump. A poorly running engine will overwork the converter and cause extreme heat buildup which will melt the catalyst into a lump. Depending on how poorly the engine is running it could melt in a trip around the block. No performance impact unless it has been abused. They do eventually wear out as the catalyst is used up.

I would expect a certified emissions inspector to know all this. It is Auto Shop 101.

[1985GMC]

Idk how this turned into an emissions fight but like I stated.... MY TRUCK IS EMISSIONS EXCEMPT. I never have to get it done again. Wow.

Thanks for the axle vent info. That's what I was looking for.

[Just call me Sean]

IT IS NOT EXEMPT FROM HAVING EMISSIONS EQUIPMENT, it is only exempt from being inspected for emissions equipment. Mr. Inspector Guy.

[kalbert]

Exempt or not, the evap can is an excellent way to vent the gas tanks. Hook it up right and forget about it. Very effective, safe, clean, efficient.

[1985GMC]

Also. Should there be a breather on the axle vents? I just looked at mine quick and there mounted correctly but just kids exposed. Like would a stupid civic breather from autozone be a good idea to put on the end of the axle vent?

[Malo83]

Tuff Crowd!

[1985GMC]

Captain Planet for days. Save the world!

[Just call me Sean]

http://youtu.be/SmypHQ5AUxQ

[donut]

Originally Posted by 1985GMC

Also. Should there be a breather on the axle vents? I just looked at mine quick and there mounted correctly but just kids exposed. Like would a stupid civic breather from autozone be a good idea to put on the end of the axle vent?

Yes, there should be a breather on the axle/axles if 4wd. (why it was suggested for venting your gas tank. ) Same breather for axles, older gas tanks, transmissions....

Last time I got some I think they were white plastic and a couple bucks a piece.

[kalbert]

For axle vents run a piece of hose from the barb on the axle up to the frame somewhere and put the breather cap there. Having it higher helps keep water out. One of those rice a roni chrome breathers will work, just as long as its mounted high and sturdy.

[dfrank]

Emissions isn't even required for inspection where I have my truck registered which is why I have it registered at my shop adress. My home adress requires emissions test for inspection so I just register my vehicles at my shop. No more emission problems for me!

[tucsonjwt]

Axle capped vents are available from Classic Parts for about $2.00 and, of course, about $10 shipping, so I bought several to bring down the "unit cost". If it was good enough for the factory then I say it is good enough for any old square to use with a short piece of hose on the sending unit. You do need to extend the hose somewhere if you want to minimize gas stink in the cab.

The axle vent is on the end of a long piece of rubber hose which terminates at a clamp screwed to a cross rib on the underside of the bed. When I converted my bed to a dump, I had to rig up a sheet metal strap and fasten it with a bolt on the differential so it could stand in mid air independent of the bed when it goes up and down.

[piecesparts]

Originally Posted by 1985GMC

Anything older than 25 years is CT Emissions Exempt. I'm a certified CT emissions inspector, My 85 GMC is exempt. My GMC has a 350 carbureted, with two 20 gallon tanks. My vapor canister currently has only fuel tank line hooked up to it. I deleted EGR, Pollution Pump, Plugged exhaust manifolds and carburetor.

So what's the deal. Can I put a valve cover breather on the fuel tank line? Basically how can I get rid of this vapor canister that is currently doing absolutely nothing?

Years ago, I deleted my canister and all of the purge garbage. Top support venting, I put a metal fuel filter on the end of the vent hose (to allow for venting, but keep dirt out) and mounted it under my radiator, out of site. Truck runs fine and only every now and then do I have some vapor build up in the on-line fuel tank. Especially on a hot day.