Itinerant Air-Cooled

As a follow-up from LiveonJG's thread, here is a little write-up on refreshing the charcoal canister on your late bay bus. If (like me) you're not interested in spending $50-60 to buy a new one, this is an easy afternoon project. It's probably necessary if you've replaced all of your evaporative lines, and still smell gas fumes. Betcha the PO of your bus never replaced it, either...

First off, remove the old canister from the engine compartment. It's held in place with a simple clamp. Remove the clamp, then disconnect the 3 hoses: One goes to the crankcase, one to the air filter, and one to the evaporative lines that go across the top of the engine compartment door.

Open up the canister to empty out the old activated carbon. Get a sharp utility knife, and carefully cut around the rim of the bottom of the canister (along the raised edge). Leave a small section uncut, so it opens like a tin can. There's a large spring underneath, which will push the end off.


You'll now be presented with the innards of the canister. Note the plastic screen with another spring in the middle. Beneath the screen is a filter. Pull out the filter, and set it aside for cleaning. I rinsed mine under the faucet, then set it in the sun to dry. Now you'll see the OEM activated carbon that was used. They are fine pellets, about ant-size. Mmmmmm, smells like volatile hydrocarbons....

Dump out the old pellets and discard. There are about 5 cups in the OEM canister. If you can find pellets this size, that's how much you'll need. I couldn't find them this small, and ended up with a larger pellet size. Buy the activated carbon at any large pet store. It will be labeled as "loose filter media". A 28oz. jug cost me about $8.

Get a colander, and rinse the new carbon under running water. You want to remove the carbon dust from the media. Lay it out on a towel in the sun to dry. In the meantime, clean up the inside of the canister with warm soapy water. I also cleaned up the large hoses with some citrus degreaser and a pipe-cleaner. Dry everything well.

Once everything is thoroughly dry, fill with your new activated carbon. The Germans were nice enough to show you how high to fill it. Put the filter and plastic screen back on, and double-check the level. The top of the center spring will be even with the lip of the canister.

Now it's time to seal the works back up. Put the large spring back in place, clamp down the lid, and seal. I used black RTV to seal mine. In addition to the clamps, I put some large zip-ties around the canister to help hold it together while the RTV cured. Looking back, I would probably use a hot glue gun next time, for a little more bond strength.

Re-install the canister into the engine bay, and enjoy the sweet (gas-free) smell of success!

That thar is a good write-up. . . for youse late model plastic canister folks.
Colin

thanks for the great writeup. Ive been 'meaning' to tackle this.....

Any way to get the broken img links going again? This looks very useful.

78 Westy wrote:Any way to get the broken img links going again? This looks very useful.

Nope. Use your imagination. Ask anew of people in the present if you should have a question.
Colin

This may help. I just did this. I used Marineland Black Diamond charcoal granules to replace to stock charcoal medium. Available at Amazon.com. Just pay attention to the order of disassembly, and watch the spring tension. Save the filter papers and reuse. I used silicone to seal the top, and I also did not cut it completely off. Leave a piece, like a hinge, and that gives you more strength after you put it back together. I used woodworking bar clamps to hold it for 24 hours until it cured. It's plenty strong.

Hi,

Finally my first post on IAC! :)

There's a similar thread on the Samba discussing the Late Bay charcoal canister refresh.

Pictures on this thread here have gone down the Photobucket drain, but fortunately there are some new pics on the neighbour forum.

There is a current discussion over there on how to best reseal/close the canister lid, as the fat spring is applying quite a bit of tension on it. It's also a plastic to plastic bond, which are generally not so easy to glue up.

bretski seems to have used black RTV about 9 years ago, which I wasn't too convinced about, as it's more a sealant than an adhesive, as far as I understand.

Jivermo used (off-the-shelf?) silicone about 2 years ago, which has the adhesive property, but I'm not sure how resistant to fuel vapour is.

So how are your resealed canisters holding up after all these years?

My canister has held up well all this time. I would consider silicone a solid fix for this.

Colin used ultra-black RTV on his EEC valve (that leads directly into the charcoal canister,) a few years ago and it held up fine. It's exposed to fuel fumes every time you're at part throttle. I say go for it, and welcome to IAC!

Robbie

Thanks! I now have a spare canister and a tube of Ultra-Black RTV, so I'll just give it a go.

I just wasn't sure about the adhesive properties of the RTV, especially as I was under the impression that the spring on the canister exerts more pressure than the one on the EEC valve. In any case, I now have all I need to try it myself. It might take me a bit, as the canister refresh moved down the priority list as some engine issues came up, but I'll report back when I have the chance to finish it.

What's the procedure for refreshing the charcoal canister for an early bay (1971)? I'm sure mine is the original equipment.

Update: found Bookwuss's write-up on early bay canisters. It looks possible, but I got to wondering who's selling canisters now? Most of the sources are for late bus or Vanagon.

JLT wrote: ↑

Thu Nov 22, 2018 1:09 pm

What's the procedure for refreshing the charcoal canister for an early bay (1971)? I'm sure mine is the original equipment.

Update: found Bookwuss's write-up on early bay canisters. It looks possible, but I got to wondering who's selling canisters now? Most of the sources are for late bus or Vanagon.

Mike's post is all about replacing the canister with the successive canisters. If you want to "refresh" a canister, that is an action verb which states in its definition: "to replace the existing charcoal pellets in your current canister with new charcoal pellets from your local fish aquarium emporium."
Game?
Colin

Amskeptic wrote: ↑

Fri Nov 23, 2018 2:01 pm

JLT wrote: ↑

Thu Nov 22, 2018 1:09 pm

What's the procedure for refreshing the charcoal canister for an early bay (1971)? I'm sure mine is the original equipment.

Update: found Bookwuss's write-up on early bay canisters. It looks possible, but I got to wondering who's selling canisters now? Most of the sources are for late bus or Vanagon.

Mike's post is all about replacing the canister with the successive canisters. If you want to "refresh" a canister, that is an action verb which states in its definition: "to replace the existing charcoal pellets in your current canister with new charcoal pellets from your local fish aquarium emporium."

I guess that this is what I was originally asking: how to replace the defunct charcoal pellets in the canister with non-defunct pellets obtainable from the fish people.

But I was also wondering if it is possible to buy a new canister from somebody else who sells them or rebuilds them or whatever, in case I decide that I'd rather have somebody else muck with it. My original request was posited by the assumption that nobody makes them anymore or rebuilds them for money.

JLT wrote: ↑

Fri Nov 23, 2018 6:57 pm

Amskeptic wrote: ↑

Fri Nov 23, 2018 2:01 pm

JLT wrote: ↑

Thu Nov 22, 2018 1:09 pm

What's the procedure for refreshing the charcoal canister for an early bay (1971)? I'm sure mine is the original equipment.

Update: found Bookwuss's write-up on early bay canisters. It looks possible, but I got to wondering who's selling canisters now? Most of the sources are for late bus or Vanagon.

Mike's post is all about replacing the canister with the successive canisters. If you want to "refresh" a canister, that is an action verb which states in its definition: "to replace the existing charcoal pellets in your current canister with new charcoal pellets from your local fish aquarium emporium."

I guess that this is what I was originally asking: how to replace the defunct charcoal pellets in the canister with non-defunct pellets obtainable from the fish people.

But I was also wondering if it is possible to buy a new canister from somebody else who sells them or rebuilds them or whatever, in case I decide that I'd rather have somebody else muck with it. My original request was posited by the assumption that nobody makes them anymore or rebuilds them for money.

There is or may be a write-up on a pellet replacement with a late plastic "disassemblable" canister. The earlier metal ones require a careful de-sweging/re-sweging. My solution is to not bother with such piffles, just keep the plumbing intact and functional and there is no fuel smell in Chloe.
Colin