charcoal scrubber

[bwsimmons@shaw.]

I removed the black cannister from the upper right hand corner of the engine compartment. It is obviously meant to clean the gases coming from the crankcase. It is filled with granuales of charcoal. Do these need to be replaced from time to time? I can't find any reference to it in the Haynes manual and I can't find a listing for this part. Any help appreciated.

[azasadny]

What year car? What engine?

[Gunter]

Should we guess on the year/type?
Before you continue, this canister could be for fuel-vapor coming from the front.
PCV is achieved by the hose from the breather cap to the oil filler stud and another hose from the oil filler stud to the black boot on top of the air flow sensor/TB.

[randywebb]

The activated carbon in the canisters can replenish itself many many times. How many years or decades it will last before it needs to be replaced, I don't know.

On some models they are NLA but can be obtained from VW for about $80.

[bwsimmons@shaw.]

Sorry for the lack of information: 1977 - 911S 2.7litre

[goldgunner]

As noted above, the charcoal container is not for the crankcase, but is for fuel tank vapor ventilation and recycle into the intake manifold.

As far as activated charcoal/carbon replenishing itself, from what I've read it's not 'self healing' or 'self reactivating'. You could use activated carbon / charcoal typically sold for aquariums, but it's a MUCH larger granule size. I was unable to find smale granule size like the oem.
After 25 years I reckon the pores in the charcoal were clogged with fuel varnish...

I've read the only way to truly reactivate the 'activated carbon' is under fairly extreme pressure and heat. Conceivably you could use a pressure cooker if you could get it to 1800 degrees F.

I took the maybe it will, maybe it won't - but it won't hurt method:
Divided the carbon into about 4 equal amounts, spread on a metal lipped pan, and gave it as much acetone as it would seem to absorb and lite it. To me, being somewhat familiar with how acetone burns, it appears that I was getting meaningful and significant residual burn and flame beyond what the acetone would have represented. To me, that meant that the varnish had become volatile and was flamed and burned off. I did this for all 4 quarters of the carbon quantity and refilled and reassembled the container. I figure at worst - no worse than it was; at best, it might have sufficiently burned out the clogged pores to allow for some more years of vapor absorption.

YMMV, regards,
Jim