When Draining the Coolant
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
When Draining the Coolant
On my 69
I am draining the coolant... I've unscrewed the drain on the engine block and opened the expansion tank as to let it all drain out. Did this drain the entire system? Or do I need to drain the radiator (which by the way has no drain plug) seperatly?
I am planning on running some water into the expansion tank to try and flush the system out a little... will this work?
When refilling.... how do I know when its full? Do I just fil the expansion tank until it reaches the proper level? or do I need to have the car running so the water pumps thorugh the system and letting air out?
I am draining the coolant... I've unscrewed the drain on the engine block and opened the expansion tank as to let it all drain out. Did this drain the entire system? Or do I need to drain the radiator (which by the way has no drain plug) seperatly?
I am planning on running some water into the expansion tank to try and flush the system out a little... will this work?
When refilling.... how do I know when its full? Do I just fil the expansion tank until it reaches the proper level? or do I need to have the car running so the water pumps thorugh the system and letting air out?
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
If there's a coolant shutoff valve for heater make sure it's open.
First, take the lower hose loose at bottom of rad & flush rad out until clear & colorless.
There's a drain plug on both sides of block ... both need to be opened & flushed until both sides clear & colorless.
Now's a great time to replace the t'stat.
To refill it'll help if you have nose of car up at slight incline:
If there's a coolant shutoff valve for heater make sure it's open:
First fill and burp/squeeze the upper hose while motor cold ... keep topping off. Then do same as motor comes up to op temp.
First, take the lower hose loose at bottom of rad & flush rad out until clear & colorless.
There's a drain plug on both sides of block ... both need to be opened & flushed until both sides clear & colorless.
Now's a great time to replace the t'stat.
To refill it'll help if you have nose of car up at slight incline:
If there's a coolant shutoff valve for heater make sure it's open:
First fill and burp/squeeze the upper hose while motor cold ... keep topping off. Then do same as motor comes up to op temp.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Hoses are new... tstat new.... heater core new.... radiator not sure, but it looks to be good and keeps engine cool. No heater valve and I dont need one.
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Originally Posted by wfo76
I like to fill the block directly thru the t-stat opening, then install stat.
Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
Originally Posted by genuine1980
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
As far as draining and filling. I fill and drain my rad and block until the water runs absolutely clear, that includes running the engine with cold, fresh water going in. I then seal everything back up and start to fill with coolant. Let's say for discussion purposes only that your block takes 20 pints. Since there will be some trapped water, I take the advertised volume of the cooling system and divide by two. In this hypothetical case, I would add 10 pints of my favorite coolant and then fill the rest of the block, rad, and coolant overflow with distilled water. Depending on how efficient I was at draining the system, I would bet that you can get close to the hpyothetical required quantity of 10 pints of water.
Disclaimer - I don't have my references handy so I really DON'T KNOW the exact amout of coolant in the system. My example tells you how to do that though.
Gary
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Originally Posted by genuine1980
Hoses are new... tstat new.... heater core new.... radiator not sure, but it looks to be good and keeps engine cool. No heater valve and I dont need one.
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
Also check your freeze plugs to see if they are rusted.
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Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
You can fill from both teh water neck and the rad cap. Both will require a top off after the car has run, maybe even two times. Use a good mixture for your application. 50/50 is perfect for most climates, and in a warm location with no freezing weather a higher water ratio will net you better cooling.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Ok so I'll fill it at the tstat opening and through in the expansion tank... I'll run the engine a few times and topoff in the expansione tank.
Next question... Do I NEED to use distilled water? I've always used a 50/50 mixture of Dexcool and Water from the faucet.
Next question... Do I NEED to use distilled water? I've always used a 50/50 mixture of Dexcool and Water from the faucet.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by genuine1980
Do I NEED to use distilled water? I've always used a 50/50 mixture of Dexcool and Water from the faucet.
Faucet water is okay unless there is a high concentration of lime or other minerals in your water. Distilled is good, but should only be needed if you have VERY hard water where you live.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Originally Posted by Durango_boy
Faucet water is okay unless there is a high concentration of lime or other minerals in your water. Distilled is good, but should only be needed if you have VERY hard water where you live.
Le Mans Master
Joined: Oct 2001
Posts: 6,798
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From: Pine Bluff Arkansas
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16-'17-'18-‘19-'20-'21
I have a buddy that is a rad. guy. He says... to use distilled water. I know, we've used tap water for most of our lives, but this is your VETTE. Splurge and spend $2 on the water.
Larry
Larry
Last edited by lebvette; Oct 26, 2006 at 01:42 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
If it has been a few years since the radiator was filled, you should do more than flush the radiator. The cooling fins and passages get crud built up on them over time, and flushing just gets the loose stuff. Go to your local auto parts store and get "radiator cleaner". The process takes a little more time, but the radiator really gets clean and cools much better when you get done. It involves draining, putting in the cleaner and refilling with JUST WATER, running for a couple of days, draining and re-fill with water again and running some more. THEN, you drain and refill with new coolant and water (50%/50% mix). I can guarantee that your car will run cooler after the cleaning job and re-fill.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Originally Posted by 7T1vette
If it has been a few years since the radiator was filled, you should do more than flush the radiator. The cooling fins and passages get crud built up on them over time, and flushing just gets the loose stuff. Go to your local auto parts store and get "radiator cleaner". The process takes a little more time, but the radiator really gets clean and cools much better when you get done. It involves draining, putting in the cleaner and refilling with JUST WATER, running for a couple of days, draining and re-fill with water again and running some more. THEN, you drain and refill with new coolant and water (50%/50% mix). I can guarantee that your car will run cooler after the cleaning job and re-fill.
And it really sucks that my radiator has no drain... I have to disconnect the bottom hose which is in a tight spot and the coolant never comes out in a nice stream. It ends up getting all over.
Pro
Joined: Nov 2004
Posts: 607
Likes: 0
From: North Alabama
Originally Posted by Durango_boy
Faucet water is okay unless there is a high concentration of lime or other minerals in your water. Distilled is good, but should only be needed if you have VERY hard water where you live.
Instructor
Joined: Apr 2003
Posts: 156
Likes: 0
From: Oakdale Ct
Funny thing... there are two drain plugs on the engine block... the one on the drivers side drained the coolant. When I opened the one on the pass side, befind the plug is solid metal... cast iron, like the block. It did not look like it was plugged by bubba. It looks like it was cast that way and never drilled open.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Originally Posted by noonie
Classic symptom of a cooling system that needs some serious flushing. When flushing a system properly these should always be taken out to drain. Take a small screwdriver or metal rod or drillbit or whatever nd work on what you think is the casting. It's really rust/scale sediment that has compacted and rusted and feels solid. Will be the same as other side and will allow you to see the space between the 2 cyl sleeves.
Also check your freeze plugs to see if they are rusted.
Also check your freeze plugs to see if they are rusted.
100%I've run into that very thing several times ... it'll come loose. Search archives for my posts about using Prestone AS100 heavy duty cooling system cleaner (2-part powder in divided canister) ... how to use & where to get ... the BEST home remedy cleaner out there bar none.