Hey there C3er's,

First of all I am not a newbie on the site..I was forced to re-register due to a problem with my laptop and the Apple/Mac folks..
I was formerly mk's78 aka Mike...............
I would like to know if there any service requirements for an OE 78 charcoal canister??
I recently purchased one from a Forum member and will be having it installed tomorrow..
I noticed that what appears to be a filter at the bottom is extremely dirty and would like to see side and check the condition of the charcoal..
Can anyone tell me how I can get into the inside of the canister to see what there is I can service?

JavaJolt78 aka mk's78......................Mike

 

You can purchase the filter from any of the corvette sites. If you are going to the trouble of looking at the charcoal, why wouldn't you just replace it? You've gone through all the effort to open the canister why not put new clean charcoal. You can get it from pet stores, its used for fish tanks

 

Here's a write-up on rebuilding a 1974 charcoal canister:
1974 Charcoal Canister Rebuild

 

I believe the bottoms twists off.

 

The 78 Chevrolet Chassis Service Manual states that you should remove the canister every 2 yrs or 30,000. Inspect it for cracks or damage and replace the bottom filter.

 

Hey there SwampeastMike and all others who responded!!!

Tx for the idea but IMHO the canister looks like it would completely deteriorate if any pressure was exerted at any end...
Just thinking out loud here...was thinking about cutting off the plastic cross piece at that bottom (filter end) and try to get into it that way???
Or perhaps you could suggest a tool etc that would be able to be used to try and twist the bottom end??
I am reaching for straws bc I'd hate to have to attempt it after it was installed!!

JavaJolt78

 

Here's another way to open the vapor canister:
How to replace charcoal in vapor canister

I used this method to rebuild the canister on my 73.

 

The plastic should still be reasonably flexible. One end or the other (I'm almost certain it was the bottom) simply twisted off from my '79 canister which is the same as '78. This is not a screw-type connection--it uses tabs and comes loose with a small counter-clockwise twist.

 

Mike - can it be twisted off to properly access & replace the charcoal without the seeming brain and knuckle damage of R&R'ing the entire canister unit?

 

As long as the activated charcoal does not get contaminated with something that plugs it up & makes it useless, it should be good. Basically, if the system is working and you are not getting fuel smells in the garage, it's doing its job. I wouldn't cut it open until you are sure it needs refreshing.

 

7-T, valid point - why waste $; My bro-in-law is in the same camp. Ain't broke, don't fix it.
But, sometimes isn't it half the fun of our hobby, staying a half step ahead of our aging classic car's imminent failures (and, the satisfying feeling of outrunning our mortality) - with emphasis on preempting anything safety, or could risk a no-start/drive situation away from home? I saw auto consumer research where women ranked raw gas smell as nearly as bad as raw sewage odors because it permeates everything including their clothing. (they also rank "grease" higher than snakes to avoid, and "wind" not far below snakes. They would rather shop for a car in the pouring rain than in wind. Don't mess with their hair.). I kinda like the smell (the study showed that many, mostly men do) but, I would recommend getting in front of this one if you have a wife that loathes raw gas smell and store your car in a garage connected to your home.