Cooling System Flush - most effective way

[98GPGT2D]

1 more question boys and girls..

1997 Grandprix GT 4 door, 3800 Series II.


What is the most effective way you have found to flush the cooling system of its old coolant.


The reason I ask is because the guy I bought the car from was a parts jockey at the GM dealership, and the car has Dex-Cool in it from a previous flush and fill.
I'm going to be replacing the coolant elbows at the same time, as per my previous post.

What's your best way/technique? I will be doing this at work. For those of you who dont know me well (basically all of you..lol) I am a farm equipment mechanic, and have access to most everything. I will be refilling with some off the shelf green coolant.



Thanks,
Jay

[Bio248]

why do you want to replace the dex? you do realize 80% of the things on the shelf at the parts store are a dex type coolant?

if you have no leaks in your system, the dex is fine and does not need to be replaced with old school green.

[98GPGT2D]

Just figured I'd get rid of it. Over on the S-series forum i'm on that's the first thing everyone recommends getting rid of.

I have the heads off my 05 Jimmy right now (Intake gaskets turned cam swap turned head job..) and the dexcool made a mess of the passages and ports.


Jay

[Bio248]

it only oxidizes and gunks up if it is exposed to air in the system, IE improperly bled systems and leaks.

[matt5112]

I had better luck with green personally.

Only took 6 months to corrode my blower case.

[BillBoost37]

I tend to flush with a garden hose by pulling the T stat, and unhooking hoses here and there. Flush the heater core, block (6 different directions) rad etc.

If you have all the possible equipment available.. hook it to a flusher machine and let it go.

As for coolant..I'd suggest the AnyColor. That way you are covered if there's some residue etc left in the engine block.

[98GPGT2D]

Thanks Bill....

As for the coolant flush machine.. no go on that one. Do they make one designed fr farm equipment? Some of our combines hold 15 gallons or better..


Jay

[BillBoost37]

I dunno man.. I live in New England.. we eat what you guys farm

[Zef_66]

I do like Bill said. Only I will fill the entire cooling system with water (in the summer) and drive it for a day or so. Drain it, flush it with a hose, and drive it again for a day. Continue doing this until the water that I drain out is as clear as the water going in. It usually takes a couple cycles like that. Then I will drain, pull the knock sensors to drain as much as I can, and even take an air hose on low pressure and blow the water out of the heater core. Then mix up antifreeze with distilled water and fill and bleed properly.

[boostedcompg]

you can make a flush machine with a 5 gal bucket, a ladder or something about 4 feet tal and some hoses and fittings. be it its not a power flush machine, it works without the mess