Anti Freeze turned brown.

chryslerfat said
I use a bottle of fast flush from Napa and run it up to temp so the t=stat opens then drive it a few blocks, shut it off and flush it with a t adaptor in the heater hose until it comes out clean then refill with water and repeat flush again if it is rusty brown. They usually come clean after 2 in a row and stay clean with a drain and fill every 2 years.

I don't have a napa real close to me. I will see what advance has for a chemical additive for flushing. Should I let the engine cool down, when I put the hose on my t-adaptor?

jos51700 said
It is rust buildup in the motor. Add a little detergent (Dawn) to the mix and go drive for a week. The pressure and antifoaming agents in the coolant keep it from sudsing.

Drain, rinse, repeat. Now, one thing you should look for...make sure that the coolant you're adding is not (at least for the time being) silicate-free.

What is silicate? Well, it's sand. Really fine sand. In the old days, silicates were used to "scrub" the system and remove water deposits, and rust. It's handy for doing that now, although it takes awhile. Coolant for aluminum engines (and I'll assume most modern coolants) typically does not have silicates, but I honestly have not checked lately (I run GO-5 in all my stuff).

You need something to break up the surface tension and scrub the crap out, and punching the block drains wouldn't hurt either. You're going to have to drive it, long term, to get it all cleaned out. Period.

Okay, funny you brought that up. I stole some dishwasher detergent from the kitchen. I had my t-stat out. And a few months ago. Added it, and let it run for about 30 minutes, then flushed with the t adapter. It came clean!
i probably should have left that detergent in longer than 30 minutes. I guess I got a little excited, and drained it out to quick.

daredevil said
I have never worried about such a thing. If the motor isnt overheating and the level isnt dropping whats the problem?Damn things 40 years old.Why waste good antifreeze?Its not like a new car with an aluminum block, radiator and pump housing. Heater cores are notorious for storing crud.I myself dont see the problem.

I called my buddy, and he said...
"Drive the damn thing and quit worrying, it's a tough engine"...LOL
It runs right at 180 degrees on the button. Thats the thermo I put in.

yooper822 said
If it was mine I'd pull the upper and lower hoses and thermostat housing and then garden hose flush the block. It's possible you have a crapload of sediment sitting in the bottom of the block and it didn't get pushed thru the system with the flush you did?

Your right. I never knew I could drain the block. I will check for that plug tomorrow on the passenger side. I never knew it had one, and hopefully it comes out after being in there that long. I guess with the tstat out, the block will refill? I know with it in, I won't have any water in the block when it is running.