: Is there an easy way to change coolant?



limoguy
10-30-07, 07:38 PM
what would you sugjest is the easiest way to do it?
remove lower hose & let drain?
drain radiater?
does it really matter what brand of coolant is used?
dont they all do the same?
thank you

Cadillacboy
10-30-07, 07:45 PM
Easiest way ? I think unplugging the drain plug lol

limoguy
10-30-07, 07:52 PM
drainplug on the radiater?
will that drain it all out?

Cadillacboy
10-30-07, 08:04 PM
It should be somewhere under the rad . Still, it might not drain it all out and this is when you can need flushing the cooling system

JimD
10-30-07, 08:47 PM
Drain as much as possible and refill with GM approved (licensed) Dex-Cool mixed at 50/50 with distilled water. Approved vendors are permitted to say Dex-Cool on the container; Havoline and Prestone are two such vendors.

Pulling the inlet and outlet hoses will drain about 4 quarts. Some models have a drain valve at the left side of the radiator. Using a little air pressure will force a little more out.

Catch the old coolant in a container as much as possible. The corrosion inhibitor package is acid based and potentially painfully fatal to small animals. Then there is the contamination of the ground water system if you let the old stuff hit the ground and go wherever gravity takes it.

I would not use any "flush" technique on my cooling system. Using a "flush" product from the aftermarket introduces who-knows-what chemicals into the system. Not for me. And, water flushing is guaranteed to lose control of the desired 50/50 mix ratio.

Back to the top; drain as much as possible and refill.

codewize
10-30-07, 09:53 PM
Here we go again.

There is no lower hose. it's in the middle of the tank. DO NOT FLUSH

There's a drain plug on the bottom of the radiator. Pull that and you'll get about half the total coolant out. That's all you need.

Put 4 GM seal tabs in the upper hose. Refill with a 50/50 mix of Dex and Distilled water.

This is NOT by any means a difficult or long procedure.

Ranger
10-30-07, 10:53 PM
The radiator has a drain plug for a reason. It is the lowest point in the system. Drain it there to get the maximum amount of coolant out.

limoguy
10-30-07, 11:27 PM
thanks everyone..I apreciate the help

CadillacSTS42005
10-31-07, 10:51 AM
this was like just covered two days ago lol

limoguy
10-31-07, 12:09 PM
thats why theres erases on pencils, cadillac. maybe you are perfect, i guess

limoguy
10-31-07, 02:29 PM
cant find the drain plug!!:banghead:

dkozloski
10-31-07, 03:04 PM
Take it to the dealer.

limoguy
10-31-07, 03:50 PM
thats the last resort..ill ask someone at the auto parts store first..i alreay have all the stuff to do it:banghead:

dkozloski
10-31-07, 04:01 PM
Do some searches on the forum before you give up. This subject has to have been covered a hundred times.

Ranger
10-31-07, 06:24 PM
There should be a hole in the splash shield right below it. Get a 3/4" dowel rod and cut a slot in the end of it. Use that as a key to turn the plug. The other alternative is to pull the splash shield. That should be relatively easy. Once you see where it is and how to open it, the next time will be a cinch.

clarkz71
10-31-07, 08:04 PM
And, water flushing is guaranteed to lose control of the desired 50/50 mix ratio.
.

Not true if you know the capacity of the cooling system, which on my 95
Eldo is 12.5 quarts.

After "distilled" water flushing drain out as much water as possible and add
6.25 quarts of dexcool (a gallon & half) and the rest distilled water. you'll have a 50/50 mix.

JimD
10-31-07, 08:34 PM
Not true if you know the capacity of the cooling system, which on my 95
Eldo is 12.5 quarts.

After "distilled" water flushing drain out as much water as possible and add
6.25 quarts of dexcool (a gallon & half) and the rest distilled water. you'll have a 50/50 mix.

Help me understand your logic that makes my position "not true".

You would drain "as much water as possible". Exactly how much water is that; "as much water as possible" fails the scientific measure standard.

Please share the methodology behind adding exactly 6.25 quarts of Dex-Cool to produce a 50/50 mix.

clarkz71
10-31-07, 08:47 PM
I thought I explained it. After draining all water add a gallon & a half
of coolant. If the system holds 3 gallons, after adding 1.5 gallons of straight
dex, what ever water was left in the block plus what you top off with can
only add up to the other 1.5 gallons.

1.5 gallons coolant (50%)
+
1.5 gallons water (50%) = 3 gallons coolant mixture or 50/50


I've done a drain and fill on my Eldo and was able to get 2.5 gallons
of 50/50 coolant mix in. So I know if I did a water flush I would have
no problem get 1.5 gallons of straight coolant in. Then top off with water.

JimD
10-31-07, 09:32 PM
I thought I explained it. After draining all water add a gallon & a half
of coolant. If the system holds 3 gallons, after adding 1.5 gallons of straight
dex, what ever water was left in the block plus what you top off with can
only add up to the other 1.5 gallons.

1.5 gallons coolant (50%)
+
1.5 gallons water (50%) = 3 gallons coolant mixture or 50/50


I've done a drain and fill on my Eldo and was able to get 2.5 gallons
of 50/50 coolant mix in. So I know if I did a water flush I would have
no problem get 1.5 gallons of straight coolant in. Then top off with water.

What works for you on a '95 Eldo engine cooling system might not apply to a later model cooling system design.

Fast forward to '98, and it is not possible to "drain" 2.5 gallons of coolant from a Seville Northstar (for example). The cross-flow radiator design could be the reason.

The original post refers to a '98 Deville.

clarkz71
10-31-07, 09:39 PM
What works for you on a '95 Eldo engine cooling system might not apply to a later model cooling system design.

Fast forward to '98, and it is not possible to "drain" 2.5 gallons of coolant from a Seville Northstar (for example). The cross-flow radiator design could be the reason.

The original post refers to a '98 Deville.

My 95 also has a cross flow radiator, I wasn't aware I had to "fast foward"
to go 3 model years. I was able to drain 2.5 gallons by removing the radiator
drain plug which is on the left front of the car and using a floor jack to raise
the right rear of the vehicle. This allows the block to drain.

codewize
10-31-07, 10:00 PM
Ranger is right. I actually found it easier to just pull the splash pan off. The plug is not in the side of the tank it's in the bottom pointing at the ground. For the life of me I can't remember which side.

A dowel with a slot in it will work but pulling the splash pan right off will also ensure you won't make a mess.

BTW when I drained my 01 I got exactly 6.25 quarts out. I was amazed, aggravated and confused but I had an exact measurement. And also amazingly enough I put 6.25 quarts back in to get it full. So having said that and others having said the same thing I think it's safe to say that you'll usually get 1/2 the coolant out.

limoguy
10-31-07, 10:29 PM
thanks everyone for the help..i will look into it getting this done.

Ranger
10-31-07, 11:03 PM
The plug is on the drivers side.

codewize
11-01-07, 12:09 AM
Just an additional side note. I used an internally marked bucket to drain into so I knew how much I got out.

Small blue bucket from Wal-Mart has measurements in 1 QT increments on the inside.

limoguy
11-01-07, 04:55 PM
Is there any chance that the drainplug could break off in the radiator while attempting to remove it? I have no idea if it was ever off. May have, who knows. just tryying to not cause more problems here:banghead:

codewize
11-01-07, 09:43 PM
I suppose it's possible but the plug is plastic so it shouldn't ever get corroded to that point.

Unless someone really overtightened it and or it's been damages I find it unlikely to be seized in there

Ranger
11-01-07, 10:37 PM
I agree with Code. Not very likely.

thu
11-02-07, 12:35 AM
I found that the drainplug fits a socket (I forgot what size) nicely.

I could drain 1.5 gallons (6qts). Total system capacity is 12.5 qts. I'm glad I took off the splash shield. Besides being easy, it prevented coolant from running all over the place.

I filled with pure water, ran the engine until upper radiator hose was hot. Turned on heater full blast. Shut off, let cool, drain. Did that three times. Took some time, but I wanted to do it. On final rinsing, antifreeze tester showed freezing point of the stuff in the radiator to be almost that of pure water.

Added 50-50 mix of water/dexcool on final fill. Used antifreeze tester to make sure I got it right.

codewize
11-02-07, 01:29 AM
Almost sounds like I knew what I was talking about.


I found that the drainplug fits a socket (I forgot what size) nicely.

I could drain 1.5 gallons (6qts). Total system capacity is 12.5 qts. I'm glad I took off the splash shield. Besides being easy, it prevented coolant from running all over the place.

I filled with pure water, ran the engine until upper radiator hose was hot. Turned on heater full blast. Shut off, let cool, drain. Did that three times. Took some time, but I wanted to do it. On final rinsing, antifreeze tester showed freezing point of the stuff in the radiator to be almost that of pure water.

Added 50-50 mix of water/dexcool on final fill. Used antifreeze tester to make sure I got it right.

limoguy
11-03-07, 02:36 PM
Finally got the dang coolant changed!! I took it to the shop,way to much trouble to do it laying on the floor! even he had trouble with it up on the lift. Bottom line is, I drained almost 2 gallons out of it. I filled with almost 2 gallons prestone extended life plus 5 GM tablets. :worship:

clarkz71
11-03-07, 03:23 PM
I'm not surprised you were able to drain nearly 2 gallons. I was able to drain
2.5 gallons by jacking up the right rear of the car to get out that last little bit.

I grew up in westhampton beach by the way. Where are you at on the island?

limoguy
11-03-07, 09:28 PM
Yes ..I got like 2 gallons out, worked out well. Im in Saint James