radiator flush?

grumpyvette

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Wanderwilly said:
I have all the Factory manuals,four volumes, I like to think the guys who built this Vette knew what they were doing.I want to flush out the cooling system, but in the book it says"no chemical flush". Today I was at a very large Chevy dealer .The parts counter man said GM makes a flush Part number 89021562. Should I use it?? The system needs a good flush. Has anyone had any experience??

most RADIATOR FLUSH ADDITIVES are a MILD acid additive that if used correctly tends to clean , loosen and removes the mineral base scale that forms on the internal surface of the radiator tubes running thru the radiator fins, if used correctly and flushed out after a few minutes they do help remove that scale or internal coating, holding it in suspension and as a result allowing it to be removed , thus increasing the thermal efficiency.
in most cases you drain the engines old anti freeze , refill the radiator with the flush additive and water and let the mix circulate in the engine for 15 minutes, you then drain the mix and refill the radiator several times letting the engine run and circulate the water to dilute the remaining flush additive at least three times to be sure its removed from the system before draining the system and replacing the fluid with a fresh 50% distilled water and 50% fresh anti-freeze mix

the bad reputation youll hear at times comes from IMPROPER USE, where the ACID ADDITIVE is left in the radiator for longer than the instructions suggest, the acid will continue to dissolve crud.
most anti-freeze is supposed to be mixed in a 50%/50% mix with DISTILLED WATER and changed out when it gets old, over heating an engine tends to drastically reduce the anti freeze expected life span, and modern engines have lots of aluminum components that electrolysis will quickly damage if you don,t keep the anti-freeze mixed in the engine at the 50%/50% ratio
Anti freeze has a semi predictable life expectancy, and generally needs to be changed out for fresh anti freeze about every 3-3.5 years or 70K-80k MILES IS A WAY TO REDUCE PROBLEMS
CHANGING YOUR HOSES AND FAN BELTS, AT THE SAME TIME IS SMART, AND WATER PUMPS SELDOM LAST FOR MORE THAN 150K-170k MILES SO YOU MIGHT WANT TO CHANGE THOSE TO PREVENT COOLANT RELATED ISSUES ON A HIGH MILEAGE ENGINE miles

so obviously the choice you make is or should be based on proper use of the RADIATOR FLUSH product, and the cars mileage and how old the anti freeze is in the car.
BTW OLD USED ANTI-FREEZE is POISON too DRINK,
so don't allow pets to drink the old antifreeze or just pour it out on the lawn

 
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Here is my newbie question of the day, since my car is on jack stands, where are the coolant block drains located on the L83 block? The shop manual is poor in this regard!
Maybe I’ll have better luck changing the coolant fluids today.
 
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There is a large hex-socket plug near the front of the block on the driver's side cylinder wall, and another near the rear on the passenger side. Will take a large allen wrench to remove. You would be advised to remove the alternator and starter; may need to regardless
Drop the starter (13mm socket, 6" extension, 3/8 drive ratchet) and then remove the 8mm allen plug (use an 8mm allen socket, 6" extension, and 3/8 ratchet again). This will drain the coolant from the passenger side of the block.

On the drivers side, there is a brass 17mm allen drain plug in the wall of the block. It is located right about the height of the alternator, and just to the rear of it. Right next to the engine mount. Use a 17mm 1/2 drive allen socket to remove it. A 1/2 drive ratchet with a flex head is better to use to remove it. That will drain the coolant from the drivers side of the block.

watching this video and reading may help as its what is posted on several web sites
 
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“There is a large hex-socket plug near the front of the block on the driver's side cylinder wall, and another near the rear on the passenger side. Will take a large allen wrench to remove. You would be advised to remove the alternator and starter; may need to regardless
Drop the starter (13mm socket, 6" extension, 3/8 drive ratchet) and then remove the 8mm allen plug (use an 8mm allen socket, 6" extension, and 3/8 ratchet again). This will drain the coolant from the passenger side of the block.

On the drivers side, there is a brass 17mm allen drain plug in the wall of the block. It is located right about the height of the alternator, and just to the rear of it. Right next to the engine mount. Use a 17mm 1/2 drive allen socket to remove it. A 1/2 drive ratchet with a flex head is better to use to remove it. That will drain the coolant from the drivers side of the block.”


This part tells me a lot as most folks just drain the radiator at the drain plug, flush the system using water, possibly several times after getting the motor to operating temp to open the thermostat, and then, finally mix the 50/50 distilled water coolant combo. I’m not sure the added complexity and work to fully drain the block drains are worth it. With my luck, I probably would have trouble opening those ports up, like my transmission plugs.

I don’t know, but I could remove the thermostat in the system to avoid having to get the motor to operating temp.
 
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