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10.12 - Replacing the Thermostats ( V12 XJ40) ( Win Dooley,  )

There are two thermostats, located at the front of A and B bank. To change the thermostats, cover fenders with protective cloth. Begin by completely removing air intake boxes for A and B Bank. A 3 to 4 inch extension is required to access the thermostat housing bolts. There are three on each housing.

On B bank (US driver's side), disconnect interfering electrical connectors and air hoses, remove radiator hose at thermostat housing, remove bolts securing thermostat housing. If housing does not pop free, tap it gently. Remove old gasket, clean up thermostat housing and bolts and replace thermostat and gasket with new parts. The process is identical for A bank, but there are no interfering electric connectors or air hoses. Replace upper radiator hoses if there is any doubt as to their integrity. Change air filters if required.

The hoses can be easily reattached by lubricating them with dishwashing soap. The snorkels can be easily replaced in the fender grommets by lubricating them with dishwashing soap. Since coolant is lost by removing thermostats, it's a good time to change the coolant. Reassemble and check for leaks.

Allow 1 hour for this task.


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