I have a 1997 Buick Le Sabre and want to know how to flush the heater core
Why are you wanting to flush the heater? Is it clogged?
Did the car have Dexcool in it that was allowed to stay in too long?
Do you have trouble with the temperature control inside? Is it able to make the temp go cool on a warm day and then move to warmer settings? Or is the electric actuator sticking?
Your quick check for the heater core is to warm up the car and touch both heater hoses near the firewall to see if both are good and warm with the heater blower off. Then run the heater blower on a fairly high speed for a minute or two and see if one heater hose is cooled down a lot. One will be cooler with normal flow, but if you have someone hold the motor at 1500 or so for a minute it will warm back up IF the outside air is cold and is taking lots of heat from the water in the core. That would be normal.
If both hoses are fairly hot with a fully warmed engine and blower running on a medium speed after driving, then you may have an actuator problem inside.
I recommend NOT using compressed air nor connecting a water hose directly to the heater opening because you can build up pressure on a core that's meant to see 15-17 pounds pressure. So you have to be gentle with whatever you use to back flush.
Post some info about your problem and that may help lead to diagnosis.
BTW, lot of the heaters clog with old Dexcool which is hard to get out. That's a problem is someone mixed old green antifreeze with the original DexCool. I don't recall if DexCool was in the 1997's or if that started in 1998.
Answers
Did the car have Dexcool in it that was allowed to stay in too long?
Do you have trouble with the temperature control inside? Is it able to make the temp go cool on a warm day and then move to warmer settings? Or is the electric actuator sticking?
Your quick check for the heater core is to warm up the car and touch both heater hoses near the firewall to see if both are good and warm with the heater blower off. Then run the heater blower on a fairly high speed for a minute or two and see if one heater hose is cooled down a lot. One will be cooler with normal flow, but if you have someone hold the motor at 1500 or so for a minute it will warm back up IF the outside air is cold and is taking lots of heat from the water in the core. That would be normal.
If both hoses are fairly hot with a fully warmed engine and blower running on a medium speed after driving, then you may have an actuator problem inside.
I recommend NOT using compressed air nor connecting a water hose directly to the heater opening because you can build up pressure on a core that's meant to see 15-17 pounds pressure. So you have to be gentle with whatever you use to back flush.
Post some info about your problem and that may help lead to diagnosis.
BTW, lot of the heaters clog with old Dexcool which is hard to get out. That's a problem is someone mixed old green antifreeze with the original DexCool. I don't recall if DexCool was in the 1997's or if that started in 1998.
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