Coolant drain plug - Help PLEASE
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Instructor
Joined: Jan 2009
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From: Houston Texas
Coolant drain plug - Help PLEASE
I'm trying to drain my coolant and I have a question: I turned the drain plug a quarter turn and wiggled it out a little but I'm not getting nearly as much coolant flow as I was expecting - does this plug actually pull completely out of the radiator? Am I just not getting it out far enough? Thanks for your input!
Le Mans Master
Joined: Feb 2002
Posts: 6,937
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From: Waldorf MD
Yes, turn it 90 degrees and pull it all the way out. Some have found spraying it with lubricant helps.
Car should be level to drain out all the fluid (use a thin pan and empty it several times).
DO NOT turn it more than 90 degrees, or you will break off the pin and need a new one. New ones cost $5 at NAPA (don't ask how I know).
Car should be level to drain out all the fluid (use a thin pan and empty it several times).
DO NOT turn it more than 90 degrees, or you will break off the pin and need a new one. New ones cost $5 at NAPA (don't ask how I know).
Drifting
Joined: Jul 2007
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After you turned it a 1/4 turn you need to pull the plug back away from the radiator a bit to get the max flow or remove it completely as described. But the flow will be more toward the back of the car than down if you remove it completely. Just need a bigger diameter pan to catch the coolant with the plug all the way out.
Melting Slicks
Joined: Apr 2002
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From: Clever, MO aka SOMO
Have you removed the cap from the holding tank by the engine..........to help vent the system and let the coolant flow better? Some guys even remove the small hose to the back of the throttle body to help vent.
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
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From: Houston Texas
Thanks for all of your replies - yes, I have the cap off of the surge tank and that did help with the flow. I had to head off to work but I made a quick stop at the Chevy dealer and bought a new drain plug and surge tank cap - I figure it is better to be safe than sorry, and I could definitely see Murphy looking over my shoulder when I was wiggling the drain plug. I'll pull it out when I get home tonight and finish the job, hopefully with no drama. I notice the new plug has a metal pin and not a plastic one - nice to see.
Does anyone see any harm in putting a very light smear of dialectric grease on the plug O-ring prior to reinstalling it?
Does anyone see any harm in putting a very light smear of dialectric grease on the plug O-ring prior to reinstalling it?
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
If you just rotate the plug 90 degrees, the pin may not exactly line up with the slot in the radiator. You may need to visually locate the slot and make sure the pin lines up before you pull the plug outward. On my radiator, the spiral part of the slot actually extends past the horizontal slot so that you can rotate the plug to the full open position without it coming out of the radiator.
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Thread Starter
Instructor
Joined: Jan 2009
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From: Houston Texas
If you just rotate the plug 90 degrees, the pin may not exactly line up with the slot in the radiator. You may need to visually locate the slot and make sure the pin lines up before you pull the plug outward. On my radiator, the spiral part of the slot actually extends past the horizontal slot so that you can rotate the plug to the full open position without it coming out of the radiator.
- I had to back off slightly from the full counter-clockwise position to get the plug out, but it did finally come out. With the plug removed, I was only able to get just over a gallon of coolant in my drain pan - did the rest stay in the engine? What came out looked just like brand new coolant, so I guess the previous owner was telling me the truth about having just had the car serviced before it was shipped to me. I'm guessing I'm okay with this "partial" change?
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
The system holds 12 quarts, and I have always been able to get close to 2 gallons out by just draining at the radiator. This includes what was in the reservoir.
Was the car low on coolant before you drained it?
Was the car low on coolant before you drained it?
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From: Houston Texas
My coolant level was right at the "Full Cold" mark on the reservoir before I started. Engine was cold when I opened the drain valve on the base of the radiator, and the car was sitting level in my garage. I even used my floor jack to raise it a bit from each side and at the rear to see if that would create some flow - I got a little more out doing this. I used a clean shallow plastic pan to catch the drained coolant, and when everything was said and done just over one gallon came out and the system took the same amount to refill it. I was expecting more like 2+ gallons to drain out based on the 12 qt. system capacity... puzzling.
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Joined: Oct 2004
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
My coolant level was right at the "Full Cold" mark on the reservoir before I started. Engine was cold when I opened the drain valve on the base of the radiator, and the car was sitting level in my garage. I even used my floor jack to raise it a bit from each side and at the rear to see if that would create some flow - I got a little more out doing this. I used a clean shallow plastic pan to catch the drained coolant, and when everything was said and done just over one gallon came out and the system took the same amount to refill it. I was expecting more like 2+ gallons to drain out based on the 12 qt. system capacity... puzzling.
If you did not drain the block, than you still have half the old in the system...
Peace
Chip
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From: Houston Texas
If you did not drain the block, than you still have half the old in the system...
Peace
Chip[/QUOTE]
I don't see where the service manual calls for draining the block - how is this done?
Peace
Chip[/QUOTE]
I don't see where the service manual calls for draining the block - how is this done?
Drifting
Joined: Apr 2007
Posts: 1,496
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From: LEBANON PA.
Hi There:
It is not possible to open the engine block drains with the engine installed in the car. Thats why you have to drain & flush the system until the coolant is clear. Follow the instructions on page 6-474.Instead of drinking water I substituted with distilled water.If your vette is 8 yrs. old like mine is, good time to change the thermostat housing.Costs about $33 from the dealer.
robsc501
It is not possible to open the engine block drains with the engine installed in the car. Thats why you have to drain & flush the system until the coolant is clear. Follow the instructions on page 6-474.Instead of drinking water I substituted with distilled water.If your vette is 8 yrs. old like mine is, good time to change the thermostat housing.Costs about $33 from the dealer.
robsc501
Thread Starter
Instructor
Joined: Jan 2009
Posts: 149
Likes: 1
From: Houston Texas
Hi There:
It is not possible to open the engine block drains with the engine installed in the car. Thats why you have to drain & flush the system until the coolant is clear. Follow the instructions on page 6-474.Instead of drinking water I substituted with distilled water.If your vette is 8 yrs. old like mine is, good time to change the thermostat housing.Costs about $33 from the dealer.
robsc501
It is not possible to open the engine block drains with the engine installed in the car. Thats why you have to drain & flush the system until the coolant is clear. Follow the instructions on page 6-474.Instead of drinking water I substituted with distilled water.If your vette is 8 yrs. old like mine is, good time to change the thermostat housing.Costs about $33 from the dealer.
robsc501
Since the coolant I drained was so clean I opted for just a refill with Dex-cool and distilled water - next time I do it I may change the thermostat and I'll take a close look at the hoses too.
