65 L79 overheating, driving me nuts

[Leif A.]

Re: 65 L79 overheating, driving me nuts

I called CRC (manufacturer of Evap-O-Rust) tech support and they said it is safe with aluminum. On their website, you'll see a video demonstrating its use on a mid-year Corvette with an aluminum intake.

My first experience with this stuff was a couple of years ago on a 1993 LT1. I purchased it from the original owner with 13k miles but the coolant looked like it had never been changed... a dark rust color with a half inch of mud on the bottom of the overflow tank. After flushing and draining the system several times with water it drained clean, but a dark red film remained on the inside surface of the pressurized expansion tank (where the cap is located). So I tried this product. A LOT more stuff (rust, sediment, dirt) flushed out. Now the inside surfaces that I can see look like new.

To this day the coolant looks fresh, the overflow tank (where sediment tends to collect) remains clean and the pH tests good. I don't sell this stuff but want to share it's the best cooling system flush I've used. Plus it's not a harsh chemical like other flushes... I wouldn't wash my hands with it, but it doesn't irritate or burn on contact. CRC claims it's "non-toxic", whatever that means.

BTW, this car has several aluminum components- radiator, heads, w/p,...

A thought about the black color- a possible source can be a deteriorating hose.

It's, also, biodegradable...really great product.