I am doing the same, I bought a guaranteed rebuildable core for $450,
they are hard to find.  Now I think I would buy one of the good used
engines on the list for $1000 or less and just put it in and run with
it.

I have not done it yet, but I know you need to use the 1.9 water pump
and t-stat housing.  Also, the 2.1 comes with an oil cooler between the
filter and the case, and I don't see any way to use this with the
earlier exhaust and plumbing, but some list members seem to think you
can.  Even if it does fit, which I doubt, it would be very difficult to
plumb in to the cooling system.

I have rejected all the conversions too, too expensive, too much time,
and too much work. Doing three would kill you, even the conversion fans
have not done that many!

I may just keep buying used 2.1 engines for 1/3 the cost of a rebuild
and never rebuild one!

As far as keeping them sealed,  I use a product called No Rosion  (They
finally are on the Web at: http://www.kars.com/showcase/no-rosion/)
which is a corrosion inhibitor for cooling systems, along with the VW
coolant.  I have 100,000 miles now on the last head replacement and am
still fine. I also have heard adding a ground wire from the right head
to the grounding point with all the wires on it on the left side can
help eliminate electrolytic corrosion.  I have done this, but I think
the No Rosion will work based on its chemistry (pH buffering plus
inhibitors.)

--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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