Total coolant flush
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Teching In
Joined: Aug 2021
Posts: 1
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From: SC
Total coolant flush I have a 93 Trans Am with 5.7 V8 that i picked up last month the coolant is crusted with the orange stuff. I want to totally flush the system and start using the green stuff. Thank you for any help.
Regardless of the coolant you use, you need to open the block galleries to properly flush the coolant. This thread shows how to do that: https://ls1tech.com/forums/generatio...l#post19670393
^ It's a total mess, but a right of passage. The alternator and starter need to come out and then coolant will fall out of the engine and everywhere. When I did this, I measured 1/2 of the coolant still in the block, so be prepared for over a gallon of fluid to come out of the block. You'll also need some thread sealant when you put the block plugs back in. "Flushing" with water or other fluids doesn't flush anything. It just dillutes what's in the system to progressively lower and lower concentrations. To get 100% of everything out, you need to:
- Drain the radiator
- Remove the overflow bottle and drain it (While you are at it, you may find it can use a good rinse.)
- Unhook the heater hoses and drain the heater core
- Drain the block
Last edited by wssix99; Aug 9, 2021 at 09:36 PM.
TECH Junkie
Joined: Aug 2006
Posts: 3,915
Likes: 676
From: Western North Carolina
I had my mechanic change out my Dexcool for the green stuff about 5 years ago. I knew it was very important to totally flush out the old and my mechanic knew that as well. I can NOT do that myself. I've been very pleased with the green stuff and no issues. You just have to stay on top of the maintenance like anything else.
