If they are going to advise Matt to continue driving his leaking Vanagon & continually adding antifreeze, shouldn’t he also be advised to use the SAFER type that is not toxic to any cats or dogs living in the vicinity, who might be poisoned by it if they ingest enough? Since he possibly leaks a quart at a time (it only takes a very small amount) & on a regular basis this would increase the chances of the possibility of poisoning someone’s pet - even his, if he has any.
I drove a 1984 Vanagon for 146,000 miles and had the same problem. The leak was however was between the cylinders and the crankcase. The problem occurred at about 50 thousand miles. It was easily solved by using a radiator/block sealer. This was added to the coolant once and the problem never occurred again.
Later, at about 100,000 miles, I visited a VW dealer and asked about potential problems that I might experience as I continued to drive this car. I was told that I might expect to have a coolant leak between the cylinders and the crankcase. When I told the service manager my experience, she said, well, you probably won’t have any more trouble. She was correct. I didn’t.
This was a common problem with early '70’s VW’s, and, as you guys said, is just from loose heads. A good tech could hear this problem on a bug/bus coming into the lot, since compression was also leaking past the head gasket.
However, loose heads in Vdubs were from the head/cylinder bolts actually pulling out of poor case castings, and tightening them will do nothing but worsen the problem. The answer was case inserts, with bigger and coarser threads, that the headbolts were then threaded into. Unfortunately, since you had to drill and tap the case, a complete takedown was in order.
We used to do this for $450. Of course, if we found bad rings, bearings, or anything else, it could go up from there 
HolySmokes
Matt, if you really like your Vanagon consider replacing the VW engine with a Subaru engine…while it’s more expensive than fixing the VW engine, it will give you another 10-20 years of reliable service, more power, and less emissions. One of the best shops in the country for VW/Subie conversions is very close to you. See Vanaru.com for more info