I've read about it and they used to use it along time ago to remove rust from blocks, etc. some of the coolant flushes use it, I got the real stuff and was told to mix 1lb to a gallon of water. My block on my 3.0 rear cylinders water jackets looked pretty bad. im guess its had a leak for sometime and the other owner just beeped filling it with water? I have 3lbs so good for 3 good flushes. im thinking of driving it for a few miles and then draining it the next day. then adding another gallon and do it again. Any ideas?

 

I use it for beekeeping! Didn't know you could use it for rust control.

I'd be a little concerned trying to remove rust inside the engine if its that bad. I guess im on the fence about this, being that pieces come loose and get stuck in heater core and radiator. As long as you back flush these two things afterwards and neutralize the acid.

 

I just finished the second flush. it disolves very well with hot water. I bought 3lbs and the first 2 time I think I was just under a pound per flush and I flush after each. my heater core was plugged and now its open but I back flushed that and that un clogged it. The next time I think I'll drive some and leave it in over night. I was told to mix 1lb per gallon, well the motor holds about 2 1/2 gal so its shouldn't be too strong? They've used it for some time to remove rust, im sure its considered to dangers' now? I think CLR might have some in it? I'll post more when Im done. thanks for the interest