What are you guys flushing your heater cores with? I have a heater core thats blocked on a 2000 Ram. I have used the Dupont NO 7 flush kit that comes with a neutralizer, but i can not find it anywhere. I thought about using Lime away or CLR.

thanks

Don

Disconnect the heater hoses at the engine & use a garden hose to backflush it...I've done it a few times with great results...

I cupped a garden hose & back flushed one that was clogged & that took care of it in one minute. You have to regulate the flow as the garden hose has 60 psi

Remove heater hoses from engine, raise both hoses in the air, fill with vinegar, let it soak for a couple of hours, flush with lots of hot water, good to go.

We backflush with the hoses of at the dealership I work at. We have al ot of problems with GM Dexcool plugging up components. Theres even a class action lawsuit for some years & models. Backflushing usually works without chemicals.
Doug

Or do what I did...I bought a tool for under $20 off the Mac Tools guy that you connect/screw onto a garden hose, then insert other end into a heater hose and clamp it on. Disconnect the other heater hose line on the core and turn on water. It has a valve stem built into the tool. Put your air chuck on it like you're filling a tire and watch the water/rust/gunk blow right out the other core line. The air agitates the water and forces it out. Works great and was cheap...one of the best, reasonably priced tools I ever bought!

Depending on severity these might help....

I have in a pinch done the following.... I arrived at a port in Korea during a snow storm to pick up a beater van. I bought and repaired it to ship from Vegas since it was warm there I never checked the heater. I needed defrost bad so I merely reveresed the hoses and flogged the vehicle ... woosh warm air

At work I unplugged a Hummer rear core by removing the hoses and using a rubber tip on a blow gun, using regulated air at low pressure in the opposite direction the coolant flowed to free it up.