heater core damage from power flushing

what is power flushing the cooling system?

Just about what it sounds like. They force water, or a water/detergent mixture, through the radiator, block, etc to flush out as much rust, stop leak, etc as possible.

If you have a weak heater core, then you could probably open it up with the flush. Or, you might flush gobs of putty-like stopleak into the core.

I don't know what psi a power flush entails, but I do know my water pressure is 60 psi or above.

The cooling system is designed to operate at about 16 psi, which is only 2 psi above atmospheric pressure at mean sea level.

SO, it is easily possible for a power flush, or GARDEN HOSE, to blow out a piece of heater core if corrosion has already weakened it. No question about that!

One must be careful when *flushing* any cooling system in an automobile. You can't just pressure-blast the thing and not expect any consequences. If that is what they did, then YES, they fvcked up your heater core, or something in the heater system.

Lg

Sounds like the power flusher is not the way to go.

I would not trust it, even on a new vehicle. This coming Spring/Summer, I'm due for a coolant change. I'll go according to the manual, which requires taking out the engine block drain plugs. As far as the heater getting flushed is concerned, just a slow flush with garden hose water. Not a full pressure blast. First from one direction, then from the other. Back and forth until I get clean water on the exit side.

In fact, the thermostat has to come out for this "operation" IIRC. So the main radiator and overflow tank get flushed as a unit, then the engine block as a unit, then the heater core as a unit. Not all strung together, which is just asking for trouble.

Lg

It is not my treatment of choice. I like it even less when people do it to automatic transmissions.

Some of the newer cars won't let you drain the torque converter at all, so either you power flush or you change the fluid you can about five times in a week to get rid of most of the old stuff.

If you change your tranny filter and service the fluid as the manufacturer recommends, you don't have to get out every drop of the old fluid.

You CAN drain it using the tranny oil cooler lines if you wish, but it really isn't necessary.

Power flushing a tranny is, IMHO, a technique designed and developed to separate people from their money. It has been cited as possibly CAUSING problems.

Changing the oil in an auto tranny is not to get rid of old oil but to replenish and maintain the lubricating and friction qualities of the oil. If done as per schedule then the partial oil changes are all that is required. I have never seen much deposit in a transmission filter even, unless the transmission is severely worn already. Transmissions tend to fail rather suddenly, mainly due to clutch disc material delaminating. Proper friction modifying properties of the oil is important for long friction material life and fairly regular partial oil changes facilitate this.

Huw