Mazda Repair: thermostat housing replacement, coolant hoses, head bolts

Question
The nipple for the two coolant hoses on my 1994 Miata thermostat housing is broken. I need to replace the housing. I unserstand it is attached to the block with an 'o' ring seal. What steps are necessary to replace the thermostat housing?

Answer
The water neck bolts directly to the front of the head.  The timing belt, upper cam gears and backing plate will need to be removed to access the two 12mm head bolts that secure it.  It uses a simple o-ring seal.  BE sure to put a light smear of RTV on the o-Ring to hold it in place and insure a watertight seal.  Excellent time to replace the belts, seals and bearings.  Depending upon miles and age the water pump also.  It will keep you from repeating in this area for awhile.

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