Hi All,

this is one good reason why you should stay away from tar type undercoating
such as Zeibart. Water sucks under by capillary action, delaminates tar from
tin, and rusts away the metal happily.  Best thing to do is scrape down
well, wire cup brush on drill works fine, will fling off the loose stuff and
melt/smear the good stuff. Gets off rust at same time (rust-paint if needed)
Wear eye protection/do-rag etc. Then re-apply since you are committed.  And
re-apply a light coat each year to keep it leak free and flexible.  I use
tar coat anywhere gravel rash will occur, but the van is rustproofed with
some non-drying 'oil' based stuff a day or two before to allow it to seep
into cracks/pinholes and any body seams.  Tar stuff still adheres just fine.
This is a fall maintanance job, one that I hate doing.

bye, Tim

'87 Syncro Westy, rustward ho!
'85 CrewCab, better shape, from a milder climate