How do you replace serpentine belt tensioner for 1998 Pontiac firebird V6 3800?

Answer 1

you can not replace the tensioner only. You must replace the entire assembly, which is cast aluminum and has passages for coolant to flow to the heater core. The part is no longer made, and you will need to find a good after-market or search junkyards. Good luck. Took me a while. then: 1. disconnect battery - check water level 2. remove serpentine belt 3. remove alternator 4. Remove coolant connections from tensioner assembly (drain all coolant) and check condition of hoses down to the heater core - these hoses are only custom-order now as well. 5. remove tensioner assembly bolts to remove the assembly from block. 6. replace assembly with new and replace coolant connections. be very careful to seat and seal properly. 7. replace alternator. (I replaced with new and this is suggested unless you have an alternator that is less than 2 years old) 8. replace serpentine belt with new - you will need to visually inspect to make sure it is aligned properly with the pulleys on the tensioner and alternator. 9. refill coolant - use a gravity funnel in the radiator so you can overfill to push air out. 10. reconnect battery 11. turn engine over. 12. bleed coolant of all air with engine running (bleeder valve is near the valve cover to the right) 13. run engine until fans come on (if fans do not come on, there is still air in the coolant and you will overheat) 14. close bleeder when all air is out and fans come on. total time is about 2 hours