95 Chevy G20 Van, 98k miles. SBC 350 5.7L. Recently bought from a third party seller. There's a rusty residue all along the coolant system. My first thought is that someone mixed dex-cool with regular green. Top of the radiator, inside of the heater core valve and thermostat house all look "rust stained". I didn't notice any sludge deposits or anything, it just seemed stained. Can't wipe it off or anything but no signed of deposits at least from the parts I replaced. i can't tell if this is the "sludge" they talk about with dex-cool and regular green mix:
I'm assuming no ones ever changed the coolant, not for a long time at least, and it's just gotten rusty from sitting. If it looks like the dex-cool was mixed with green let me know. Either way,I want to flush it and get everything out and I've heard of so many different ways to do it, just hoping for some clarification on what has worked best for people. I've heard:
Which one is the best option for my issue? Or at least, which will likely be effective and won't damage my system? Anything I should look out for when flushing? Assuming I need to flush from the radiator as well as the block. Haven't done a coolant flush in a while and the last flush I did was on a 325i... any help appreciated.
I'm assuming no ones ever changed the coolant, not for a long time at least, and it's just gotten rusty from sitting. If it looks like the dex-cool was mixed with green let me know. Either way,I want to flush it and get everything out and I've heard of so many different ways to do it, just hoping for some clarification on what has worked best for people. I've heard:
- Flush with straight water with a hose
- 50/50 water and white vinger mix
- fprestone radiator flush and water
- cup of cascade dishwasher detergent, + water
- caustic soda + water
Which one is the best option for my issue? Or at least, which will likely be effective and won't damage my system? Anything I should look out for when flushing? Assuming I need to flush from the radiator as well as the block. Haven't done a coolant flush in a while and the last flush I did was on a 325i... any help appreciated.