I just bought a 2.1 from someone who did this conversion, and will be
installing it in the next couple of weeks.

Everything from the 1.9 is used on the 2.1, including the exhaust.  The
one problem is the external oil cooler that the 2.1 requires which is
between the oil filter and the case.  There is no room for this, nor is
there H2O plumbing on the 1.9, so he used an external oil filter adapter
mounted on the side of the engine compartment, and tapped the thermostat
housing and waterpump for brass fittings to attach the coolant hoses.
Seems like a very good way to do it.  I had an oil analysis done on this
engine and there are no coolant leaks or indication of bearing wear.

Everyone on the who has commented on list says not to leave this cooler
off, the 2.1 runs hotter and needs it.
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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