Charcoal cannister

Ji Jacques - What's the purpose of this canister? Thanks,

 

Generally a carbon canister is part of an Evaporative Emissions Control system (EEC or EVAP). As such, I believe that they are not standard equipment in our cars, and that if one is present then it was an aftermarket mod added to comply with EPA or CARB regulations. The most primitive system is one that is merely attached to the fuel tank. The carbon in the canister "stores" fuel vapors from the tank when the engine is not running, and releases them into the induction system when the engine is running. If your car is subject to a regular smog check at registration renewal time, and if that check includes a visual inspection, it's advisable to leave the equipment in place. I believe that the charcoal may lose its storage ability over time, such that a 30 year old unit might not even be doing anything. On the other hand, as long as the connection to the induction is not leaking and causing a vacuum leak, it's not doing any harm either.

 

Well dangit I learn a lot around here. Thanks very much 180 Out! (Like your alias btw - I can relate.)

 

The item on the top of the engine is not a charcoal cannister and has no impact on emissions, it is simply a reservoir for air and I think only there to help balance idle air flow. Mine was a bit rusty and may have been near a rust-hole, I de-rerusted it, put POR-15 over it and then crackle paint...Lee

 

It sounds as if I was wrong, when I wrote that the thing that Jacques describes as the charcoal canister is not standard equipment on our cars. His description of the location, in the cylinder valley behind the oil filters, says that he's talking about the system that's depicted in the attached screen capture from Ricambi's on-line catalog. In this drawing the canister itself is called "Assieme sfiato e blow-by," which Google translates as "Together and vent blow-by." Although I know no Italian, I think a more idiomatic translation would be "combination crankcase ventilation and blow-by cannister."

You can tell by the hose routing of this system that blow-by gases are carried from the crankcase -- specifically by means of the oil filler neck -- to the canister, and then vented to the induction path, above the throttle body. I did not know that this canister has charcoal in it, but that makes sense, if it's going to be storing hydrocarbons. However, I would not call this an EEC or EVAP system, I would call it a PCV system.

Edit: while I was typing this, people with actual knowledge -- Lee and Bruce -- posted up and pretty much preempted me. While I might try getting up earlier to keep ahead of the game, that might work with Bruce in Tampa, but I'm not even going to try to get up earlier than Lee in Taipei.
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Jacqques;

I believe this is Ferrari's version of a pcv valve, returning crankcase vapors back into the induction side of things. This canister is pretty light, it felt like an empty can when I removed mine for refreshing. It seems to be the 1st part on the engine that goes south on ya. B.

 

My '84 does have a real carbon canister. It was obviously installed during 'federalization' since it has a "Goodwrench" sticker on it. It is discretely hidden behind the wiper arms just left of center. It does (or tires to) just what 180 says. There is a vent line from gas tank to the canister and a few other locations around the engine. Two years ago I had an issue that the gas tank was pressured on warm days when opening the filler cap and I mean a fair bit of pressure! After tracing all the lines, I found the one from the tank to the carbon canister was blocked. I cleared the line and no more pressure at the filler cap.
Ken