The thermostat is generally located near the top of the engine
where the radiator hose connects. It is located behind the housing
that is held on by a couple bolts.
To cut costs you can find a decent Kubota I2900 that is used at
www.tractorhouse.com for about $8000-$8500. www.tractorbynet.com
also offers a used Kubota I2900 for a higher price.
Where can I find a Kubota 12800 for farming?
You can find a Kubota 12800 for farming at this link that I am
providing for you:
http://www.sears.com/shc/s/c_10153_12605_Appliances_Commercial+Appliances
Where can I find Kubota L2800 maintenance supplies?
A great website to find all the needs from extra parts to
regular, everyday maintenance supplies for your Kubota L2800 is
http://www.messicks.com/TractorParts/Kubota/l2800.aspx