It's a while since I've changed a thermo on a mk 1 Punto, have changed a headgasket in the past. Think it's on the top hose, you can't miss it. Follow hose from rad & you will find thermo housing with hose attached. Easy diy change. You will be better to drain all coolant & replace anti freeze too. After changing thermo, you may need to use gasket sealant paste. If your old thermo gasket breaks up when taking thermo off. If so, clean thermo housing up, then apply paste.
Make sure your keeping an eye on dash board lights when starting car up again, watch for air lock. don't want head to over heat after thermo. If water temp light comes on, switch engine off immediately & bleed air from system. Most cars have a coolant temp, not the old Punto.
George.
December 2008
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