JD1964

I looked for a few minutes but haven't found it. Is there an article or thread on here for DIY coolant flush and change? My 51k mile '96 still has the Dexcool and I would prefer to get it out of there.

Thanks.

ccrazor

Google is your friend..

https://www.google.ca/?gfe_rd=cr&ei=...RVETTE+DEXCOOL

Cliff Harris

There is nothing wrong with Dexcool as long as it was the only kind of coolant in the system.

To completely drain the cooling system you need to drain the radiator (roughly 1 gallon) and pull out the knock sensors (roughly 1 gallon per side). Also drain the overflow tank.

To do a complete cooling system flush, drain the whole system. Fill with plain water. Run the engine up to temperature. Let cool and drain. Repeat until the coolant is completely clear. This is the method spelled out in the FSM.

Fill with 50:50 antifreeze/water. Everybody I know recommends using distilled water. The FSM does not. The antifreeze companies do not. Use your own judgment. I can buy a gallon of distilled water for 89 cents at my local grocery store, so it's cheap enough...

bac22

Why? Whats wrong with Dexcool, I was under the impression it's better than the green stuff.

I use the Prestone Antifreeze Flush and Fill Kit to make it much quicker and ensure a complete flush including heater core.

JD1964

I suppose keeping Dexcool is an option. Is 96 the first year it was used in the Corvette?

Cliff Harris

Yes.

mixalive

Just don't mix the stuff. It creates a gel and clogs things up. And looks ugly as well.

dayle97se

wasn't dexcool the factory fill for our 96s? why would anyone want to change that? I could understand draining and refilling with fresh dexcool...

Cajun CB

When you drain your system, you only get about 2 gallons of the 4 or so. If you refill with the premixed 50/50 you will only be about 25% if you do a good flush.

You can get more out if you remove the block drains but they are a PIA.

dayle97se

Is the dexcool supposed to be 50/50? If so, it doesn't matter how much you drain, because you're still refilling with the same 50/50 proportion.

Cajun CB

If you flush the system it will matter because the fluid left in the retained part will be straight water.

dayle97se

Gocha. I was referring to draining and refilling a couple of times, as opposed to draining, flushing, and then refilling.

Cajun CB

I just went through this. Mathematically it takes 6 drain-run-drain cycles to get the old stuff below 1%. It still looks contaminated after 6 cycles. I had to go 10 to feel like it was well done. Distilled water is fairly cheap.

Tom400CFI

I agree with others who posted that Dexcool works and why change to something else?

I disagree w/the FSM method of flushing b/c it takes too long and creates too much waste liquid.

My method is simple and works even better than the FSM method;
*Drain radiator, then engine block.
*Run Garden hose through radiator until clear
Disconnect heater core hose and run garden hose through that, until it runs clear out block drains.

System is completely clean, including the heater core (which simply draining system does not accomplish).

Install all drain plugs, fill and bleed system. Done.