SirRobyn0
Full Access Member
- Joined
- Dec 6, 2019
- Posts
- 6,755
- Reaction score
- 11,402
- Location
- In the woods in Western Washington
- First Name
- Rob
- Truck Year
- 1984
- Truck Model
- C20
- Engine Size
- 305
So at the shop this is how we would tackle a clogged heater core.
Remove both hose off of the heater core, plugging the lower one after it drains. Then we'd fill the heater core with flush chemical. We have been using the prestone stuff. All coolant flush is pretty weak compared to some of the old fashion stuff that was made with acid, so you really don't have to worry about the modern stuff doing damage. Leave it in for at least 1/2, and hour is better. Then flush the core in both directions, and don't be stingy with the water or amount of time of flushing. Never used hot water as we just have a hose near one of the doors. Some guys will try to blow compressed air though the core, but please don't. I've never seen a heater core damaged from a water back flush, but I've seen guys blow them out when they jam 100+ psi of air in there.
It'll work, but in my experience typically it's only a bandaid and 6 mnts to a year later it's clogging up again.
Remove both hose off of the heater core, plugging the lower one after it drains. Then we'd fill the heater core with flush chemical. We have been using the prestone stuff. All coolant flush is pretty weak compared to some of the old fashion stuff that was made with acid, so you really don't have to worry about the modern stuff doing damage. Leave it in for at least 1/2, and hour is better. Then flush the core in both directions, and don't be stingy with the water or amount of time of flushing. Never used hot water as we just have a hose near one of the doors. Some guys will try to blow compressed air though the core, but please don't. I've never seen a heater core damaged from a water back flush, but I've seen guys blow them out when they jam 100+ psi of air in there.
It'll work, but in my experience typically it's only a bandaid and 6 mnts to a year later it's clogging up again.