When I got our 82 vanagon it had lots of mold on the inside of the pop top.  I just mixed up a spray bottle full of about a cup of bleach and couple quarts of warm water.  Put on some crappy clothes and pulled the mattress  out of the top bunk.  Then I just sprayed the bleach water all over the inside of the top.  Soaking the whole thing down.  Most of the mold had built up in those little screened off channels at the very top corners.  Well after a few minutes for the bleach to go to work, the mold just disipears.  The bleach kills it and gets rid of the black stain.  Its like magic.  Have a few old towels up there with you to mop up dripping areas of the top and just keep laying the bleach water to it till all the stains are gone and all the mold is dead.  Once its all dead it will take much longer to come back.  Its been a year now and no black mold on the inside of the top.  Soapy bleach water works to clean the outside of the top as well.  Just need a long handled brush to get to it.

David
1982 Westy

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