: Changing Coolant and the Right Number of Tablets



wilsonmi
05-17-04, 10:39 PM
OK - Im new to Cadillacs and new to the Forum. I did the searches on coolant changes and read as many as I could until my eyes got blurred.

I've got a 99 STS with 68K on it. The water pump is starting to seep which I've heard is fairly common. So I'm going to replace it in the next couple of weeks. While I'm at it, I'll replace the coolant. In several of the threads I've read, I saw people talk about using powder and some say tablets instead. Some of the threads say 6 tablets - the sticker under my hood says 3. What's the right number?

By the way, before anyone asks I'm going to use a new pump - not rebuilt. My brother got what I thought was a good price - $75.00 for the pump and the special socket. The dealer wanted $570.00 to replace it.

P.S. I bought it used with 64K on it and I love the car.

Thanks for any advice
Mike

growe3
05-17-04, 10:54 PM
Put in two tubes of Bars Leak Golden Seal (.75 oz each) or the equivalent in the tablet form. If using the tablets, crumble a bit to help it break down. They are the same ingredient, ginger root.

Be sure to only place it in one of the radiator hoses. Usually pull the lower hose loose from the water pump and add at that point.

DO NOT PUT IN THE SURGE TANK, it will not circulate properly.

-George

wilsonmi
05-20-04, 10:56 PM
Thanks for the advice. I appreciate it.

Mike

JimD
05-20-04, 11:22 PM
And be sure to replace any lost coolant with a 50/50 pre-mix of distilled water/Dex-Cool.

Anthony Cipriano
05-20-04, 11:54 PM
The manual will say 3 of the GM coolant supplement pellets for the Northstar. The 4.x engines were recommended for 6 of them due to the greater chance of an internal leak of coolant directly into the oil. I always recommend 6 of the GM coolant supplement pellets/2 tubes of the BarsLeaks golden seal powder for either engine. It just provides extra protection against leakage and wont hurt a thing.

It's a good time to drain and refill the system with fresh 50/50 DexCool/distilled water as the 5year/100K life of the DexCool from the OEM fill is near. The water pump will be the easiest you've ever changed. It's hard to believe the dealers can somehow justify charging $570.00 to change one. That's about $450.00 profit I'd say. With the special tool it's a snap. Remember that the water pump cartridge is removed by turning it clockwise as viewed from over the left front fender looking into the water pump cavity from the backside after removing the cover. It is installed by turning the special tool counterclockwise - a "left handed thread" install. When the old pump is out remember the o-ring seal that is in a groove in the water crossover casting. Look inside the housing when the water pump is out and you will see it. Put a new o-ring in the groove (should be in the kit with the pump) and make sure it is seated and lubed with antifreeze when installing the new pump.

Check the water pump drive belt and tensioner. The tensioner may need to be exercised and the pivot lubed to keep it moving freely.

lowscola
06-01-04, 03:47 PM
I was getting the Check Coolant Message and figured I might as well drain and fill instead of just topping off. Prestone makes the Dexcool compatable extended life coolant so that wasn't a problem. But two parts stores I went to didn't have the recommended supplement:

a pic for future reference since this seems to be a hot topic
http://www.barsproducts.com/images/images/cooli1.gif

so I purchased two bottles of the R6 liquid, mixed one bottle with my 50/50 water & coolant mix and then filled up.
http://www.barsproducts.com/images/images/origin.gif

the R6 and the supplement seem to do the same thing or am I badly mistaken.
Holding off on adding the second bottle.

RLLOVETT
06-01-04, 08:32 PM
Thanks for the thousand word pictures!!

jgr7
06-01-04, 09:54 PM
What color was the R6, I don't think it is the same as the G12BP or HDC, that are made from ginger root and ground up shells. Some of that stuff has some kind of Aluminum powder in it that could be trouble.

Jeff

RLLOVETT
06-01-04, 10:11 PM
Pretty sure it's all the same dang stuff...hope I'm right since I used the bottles until I could find the pellets!

lowscola
06-02-04, 12:01 PM
What color was the R6, I don't think it is the same as the G12BP or HDC, that are made from ginger root and ground up shells. Some of that stuff has some kind of Aluminum powder in it that could be trouble.

Jeff

Dark brown.



Thanks for the thousand word pictures!!

Don't hurt you brain trying to read through all of those words...

sportyal
03-28-06, 12:12 AM
what is the procedure to change and flush the coolant in a 2000 catera

GreenMachine
03-28-06, 06:21 AM
careful which prestone you use, theres one with the GM Approved logo on it (thats the one you want should say dex-cool on it also) then there is one that just says Compatable with all coolants, don't use that one, it can be used but better to stick with the GM certified one.

My dealer replaced the waterpump and out the door for just under 375. Half is labor, don't mind that to much, those mechanics need to eat..even if sometimes it's steak :) Plus since its really my dads car he payed :)
Invoice:
Click for Picture of Invoice (http://www.cadillacforums.com/forums/attachment.php?attachmentid=15938&d=1133926949)

I've also been told to stay away from the bars-leak, been told it could cause the heator core to get clogged. Unless thats a differant kind than what your talking about.

Rob S
03-28-06, 09:58 PM
I just did my 99 STS waterpump and coolant change. I used a new waterpump, all 6 tablets (bought from Dealership in a 6pk), and Prestone Dexcool. I left the tablest whole and inserted them in the lower hose. Worked fine, no leaks, or anything. Good luck.

boxhalr188
02-15-07, 04:06 PM
I am going to drain and add new coolant. I am not familar with the tablets, what are they and what purpose do they serve? The car is a '98 Eldorado ETC. Thanks for any info.

Ranger
02-15-07, 04:23 PM
They are a cooling system supplement (sealant). The purpose is to prevent nuisance leak & seepage. They can be purchased at any GM dealer or Walmart, or most parts stores. If you get them from other than a dealer look for Barsleaks products. The tabs product code is HDC and the powdered version is G12BP. Put them in the radiator hose, NOT the surge tank. Do a search for Barsleaks, tabs, cooling system supplement, HDC, G12BP. You should find enough reading to keep you out of trouble for days.

mr_mr11
02-18-07, 05:58 AM
They are a cooling system supplement (sealant). The purpose is to prevent nuisance leak & seepage. They can be purchased at any GM dealer or Walmart, or most parts stores. If you get them from other than a dealer look for Barsleaks products. The tabs product code is HDC and the powdered version is G12BP. Put them in the radiator hose, NOT the surge tank. Do a search for Barsleaks, tabs, cooling system supplement, HDC, G12BP. You should find enough reading to keep you out of trouble for days.

Ranger, when I was at my local parts desk at the Caddy dealer last week picking up a water pump, I asked them about installing the pellets. They told me that they no longer put them in N* engines b/c they tend to clog up the radiator? They also no longer carry them in stock for sale. Any truth to this notion? mr_mr11 :confused:

JimD
02-18-07, 10:15 AM
....they tend to clog up the radiator?....
Not so.

The proper material installed properly will not clog the radiator. The tablets or powder is only an insurance policy protecting you from minor nuisance leaks.

You decide.

Ranger
02-18-07, 11:04 PM
If that were true, all the earlier Northstars plus the 4.9's, 4.5's & 4.1's would have clogged radiators and we would certainly have heard complaints here. I think the reason that they quit using them is because they make the coolant look muddy, thus people where complaining that the cooling system is going bad and asking that the coolant be changed while under warranty. Especially if they have been on the internet and were reading Dex-Cool horror stories.

Mountie
02-19-07, 03:24 AM
I replaced my North*, and refreshed everything. Just a little suggestion about installing your waterpump. ( You can do it yourself ).... When using that special socket installing the waterpump, & as you turn it to lock it in place, notice the bent-up tabs...... They will flatten very easy, if you use a breaker bar!! Careful not to go to tight, to the poing you flatten the tabs, and 'spin' the waterpump past the stops. I was told to use just grease at the '0' ring area, and it's to keep the pump from corroding / rusting.

mr_mr11
02-19-07, 09:38 AM
I replaced my North*, and refreshed everything. Just a little suggestion about installing your waterpump. ( You can do it yourself ).... When using that special socket installing the waterpump, & as you turn it to lock it in place, notice the bent-up tabs...... They will flatten very easy, if you use a breaker bar!! Careful not to go to tight, to the poing you flatten the tabs, and 'spin' the waterpump past the stops. I was told to use just grease at the '0' ring area, and it's to keep the pump from corroding / rusting.

Mountie - I echo your comments on the water pump replacement however I had to use an impact wrench to get my old one off and get the new one back on - the handy socket I purchased from Napa worked well.

Thanks to all for the good posts!! mr_mr11 :thehand:

26TP
03-13-08, 09:00 AM
Apologies for what might seem like a dumb question,

After draining all of the old coolant, should you flush cold water through the system to remove any old coolant deposits?

Ranger
03-13-08, 12:19 PM
No. You never get all the old coolant out, so I you flush it, you won't get all the water out. Then you'll have to use a refractometer to get the correct 50/50 mix.

tateos
03-13-08, 05:51 PM
Mountie's warning is correct....I know....

26TP
03-14-08, 04:39 PM
Great, thank you very much to all who replied for your help.

And finally is the 50/50 mix rule super critical?

JimD
03-14-08, 06:44 PM
....And finally is the 50/50 mix rule super critical?It's important enough to put some effort into measuring carefully if you are doing the mixing.

Not only does the Dex-Cool provide freeze protection. It also elevates the boiling point of the mixture. And you really want the boiling point of the mix to be in the neighborhood of 265 degrees F @ 15 PSI pressure. If you end up with less than 50% Dex-Cool and more than 50% water, the pressurized mixture will vaporize at less than 265 degrees F @ 15 PSI. How much less won't matter when you are stranded on the side of the highway some dark and stormy night.

It might seem super critical at that point.

racinrod67
04-30-08, 02:34 AM
I picked up some cooling system seal tabs from the dealer today, part #3634621. I plan on putting all 6 tabs in the system along with fresh 50/50 Dexcool mix. I understand not to flush the cooling system with fresh water, just drain and refill, correct? One other question, the parts guy and the package instructions say to crush up the tablets, add to the coolant and pour directly into the radiator, so is that the best way, mix and pour into the surge tank?

AJxtcman
04-30-08, 08:59 AM
I picked up some cooling system seal tabs from the dealer today, part #3634621. I plan on putting all 6 tabs in the system along with fresh 50/50 Dexcool mix. I understand not to flush the cooling system with fresh water, just drain and refill, correct? One other question, the parts guy and the package instructions say to crush up the tablets, add to the coolant and pour directly into the radiator, so is that the best way, mix and pour into the surge tank?

You may want to look at this
#51 (http://www.cadillacforums.com/forums/1458731-post51.html)

Submariner409
04-30-08, 10:00 AM
racinrod, If your manual calls for the cooling system tablet supplement, it generally specifies 3 tablets crushed in the lower (return) radiator hose. Using the whole package is unnecessary overkill and could very well lead to clogging of some cooling passages.

As AJ's lengthy thread (referenced above) says, the supplement tablets were and are not designed to be a cure or preventative for head gasket gas leaks into the coolant; rather they were used to seal nuisance weeps from gasket irregularities and aluminum casting pososity. General Motors is not the only engine manufacturer to use the product, not by a long shot.

Drain as much old coolant as possible and refill with a 50/50 mix of the coolant specified in your manual.

Ranger
04-30-08, 10:56 AM
They need to be crushed when putting them in a radiator because of the oil or trans cooler line in the side tank. That prevents you from putting whole tabs in there. On the Northstar you can just pop the whole tab in the radiator hose.

krimson_cardnal
04-30-08, 11:32 AM
:yeah: Upper hose will do - NEVER in the surge tank. K_C

racinrod67
04-30-08, 11:53 AM
I am not trying to repair anything, I am not experiencing any coolant leaks this is purely a preventive maintenance issue. I have read the past threads on this topic, which include varying opinions and advice. Then add the instruction I received from the dealer (add all 6 tabs) and what I've read in my aftermarket repair manual (add three tabs but flush cooling system repeatedly until water is clear) and I find myself with more questions than I started with. But if the seal tabs are a good idea to add to new coolant in a N* with over 100,000 miles, then I will drain the system, not flush it, crush three tabs and place in the lower rad hose and fill with 50/50 mix of Dexcool and distilled water. Sound good, I'll wait for your replies, thanks guys.

krimson_cardnal
04-30-08, 12:05 PM
That'll work. Tabs give a safety factor to minor gasket leaks in the cooling system, not necessarily the head gaskets. Last time I had a dealer do it they put six tabs in the lower hose. I maintain my system the same way. After market manuals are not a GM FSM, I wouldn't use one. I'm not running Dexcool. System didn't have it when I acquired the car and as I understand things, once Dex has been replaced with conventional coolant no sense trying to go back, just change it on a two year cycle. K_C

Submariner409
04-30-08, 02:12 PM
................from the 2002 Seville/Eldorado GM Factory Manual.

Click on the pic and scroll in.

AJxtcman
04-30-08, 02:41 PM
2000 Northstars (previous years are similar)

Filling Procedure
Notice: Do not add cold water to the cooling system with the engine at or above operating temperature. Adding cold water causes rapid cooling, resulting in possible engine damage.

NOTICE: When adding coolant, it is important that you use GM Goodwrench DEX-COOLŽ or HAVOLINEŽ DEX-COOLŽ coolant. If Coolant other than DEX-COOLŽ or HAVOLINEŽ DEX-COOLŽ is added to the system the engine coolant will require change sooner; at 50 000 km (30,000 mi) or 24 months.

Notice: Do not use a solution stronger than 70 percent antifreeze. Pure antifreeze can freeze at -22°C (-8°F).

Notice: This engine uses DEX-COOLŽ and GM coolant supplement (sealant) P/N 3634621 specifically designed for use in aluminum engines. Failure to use the engine coolant supplement (sealant) and the approved coolant antifreeze could result in major engine damage. When refilling the cooling system, add three pellets of the engine coolant supplement sealant GM P/N 3634621 to the lower radiator hose.

Important: This engine is not equipped with block drains, 2.5 l (2 qt) of residual coolant remains in the engine block.


Refill the cooling system. In order to ensure sufficient engine cooling, freezing and corrosion protection, maintain the protection level at -37°C (-34°F) or lower.
Start the engine.
Place the heater and A/C control in any A/C mode except Max and the temperature in the highest setting.
Allow the engine to continue idling until the lower radiator to water pump hose is hot.
Turn OFF the engine.
Allow the engine to cool to outside temperature. Ensure the coolant level in the surge tank is at the proper level (1).


2001+ Northstar's

Filling Procedure
Notice: Do not add cold water to the cooling system with the engine at or above operating temperature. Adding cold water causes rapid cooling, resulting in possible engine damage.

NOTICE: When adding coolant, it is important that you use GM Goodwrench DEX-COOLŽ or HAVOLINEŽ DEX-COOLŽ coolant. If Coolant other than DEX-COOLŽ or HAVOLINEŽ DEX-COOLŽ is added to the system the engine coolant will require change sooner; at 50 000 km (30,000 mi) or 24 months.

Notice: Do not use a solution stronger than 70 percent antifreeze. Pure antifreeze can freeze at -22°C (-8°F).

Important: This engine is not equipped with block drains, 2.5 L (2 Qt) of residual coolant remains in the engine block.


Refill the cooling system. In order to ensure sufficient engine cooling, freezing and corrosion protection, maintain the protection level at -37°C (-34°F) or lower.
Start the engine.
Place the heater and A/C control in any A/C mode except Max and the temperature in the highest setting.
Allow the engine to continue idling until the lower radiator to water pump hose is hot.
Turn OFF the engine.
Allow the engine to cool to outside temperature. Ensure the coolant level in the surge tank is at the proper level (1).

racinrod67
04-30-08, 07:53 PM
Hey guys, thanks for all the detailed responses, I think I better get a factory service manual and throw this aftermarket one away!:thumbsup:

jeffrsmith
05-03-08, 10:40 AM
I'll Second that

NHRATA01
05-05-08, 10:08 AM
So does the 2001+ not specify the addition of the sealant tablets?

Ranger
05-05-08, 10:30 AM
I forget exactly what year GM stopped using them. My '03 doesn't. If they are recommended for your car, there should be a sticker on the radiator shroud.

Eric
05-05-08, 10:54 AM
From GM Techlink March 2004:



Cooling System Seal Tabs What’s made of ground-up ginger root, almond shells and binder? And causes confusion in auto service departments?

Some people call them coolant pellets, but the proper name is Cooling System Seal Tabs. And we hope to clear up some misunderstandings about them.

How They Work
Seal tabs are dissolved in the engine coolant and the resulting fibres circulate through the cooling system. At a microscopic level, the tabs break down into irregular, long, thin fibres. When a small leak or seepage occurs, the coolant carries the fibres into the opening, where they cluster up and jam together. (Think of logs and branches in a beaver dam.) This mechanism is very effective at stopping leaks. Any fibres that make it to the surface will crust over and enhance the seal.

This sealing method is useful only for small-scale leaks and seepage, and tends to work best in conditions where the surrounding parts aren’t moving. The seals tend to break down in areas between metals that are expanding and contracting with temperature changes, for instance.

A Secondary Benefit
The traditional green-colored coolant, used until DEXCOOLŽ was introduced in 1996, contained silicates, which deposit on cooling system surfaces. The tiny fibres from the seal tabs acted as scouring pads, removing silicate deposits from the water pump seal faces, which contributed to longer water pump seal life.

Side Effects of Seal Tabs
In addition to the benefits of sealing small leaks and scrubbing silicates from water pump seals, seal tabs also have some side effects.

After awhile, a brown, dirty-looking stain may form on translucent coolant bottles. Residue may form on the backside of the radiator cap. And deposits that resemble rust may be found in the cooling system.

These are not problems, in the sense that they cause no physical harm. But their appearance can be alarming, especially on a new vehicle. Both customers and well-intentioned technicians can be misled by these deposits.

Another side effect comes from overuse. When seal tabs are used in the prescribed amounts, they will not cause restrictions or plugging in an otherwise properly operating cooling system.

But, if a little is good, a lot must be better. Wrong!! Overuse can lead to plugging, especially in the relatively small tubes used in heater cores.

Some History
There was a time when seal tabs were installed in every new vehicle, at the factory, to account for the inevitable small leaks that occur in castings, joints, and so on. By the mid ‘90s, manufacturing and machining techniques had improved to the point where the seal tabs were no longer needed on a universal basis.

With the introduction of long-life coolant, silicate deposits were no longer a concern, so the scrubbing action from the seal tab fibres was no longer needed.

TIP: GM plants, as well as other manufacturers, still occasionally use seal tabs to address specific concerns.

Today’s Recommendations
In short, GM no longer endorses universal use of seal tabs. Procedures in SI have been specifically written to discourage their use in most cases.

When a condition appears in which seal tabs may be beneficial, a specific bulletin is released, describing their proper use. One such bulletin is Customer Satisfaction Program 03034, dated 7/7/03. This applies to specific 3.8L engines only, and is in effect until July 31, 2005.

TIP: After performing the procedure in the bulletin, be sure to install a recall identification label to the vehicle to indicate that the seal tabs have been installed.

TIP: If seal tabs were installed in a vehicle at the factory, it’s OK that the proper amount of tabs be installed if the coolant must be drained and replaced.

What’s a Recommended Dose?
TIP: Use this information only when instructed to do so by bulletin or SI procedure.

The proper number of Cooling System Seal Tabs depends on the capacity of the vehicle’s cooling system. Use between 1 and 1 1/2 grams of tabs per liter of cooling system capacity.

TIP: Cooling System Seal Tabs are packaged in two sizes.12378254 Small tabs (4 grams each) 5 tabs per package
3634621 Large tabs (10 grams each) 6 tabs per package

- Thanks to Greg Cockerill and Gary McAdam

Ranger
05-05-08, 06:26 PM
Thanks Eric. I'm going to copy and sticky this for future reference.

krimson_cardnal
05-05-08, 11:48 PM
:yeah: GREAT info long sought by many! Kudos to Eric. K_C

racinrod67
05-07-08, 01:27 AM
The proper number of Cooling System Seal Tabs depends on the capacity of the vehicle’s cooling system. Use between 1 and 1 1/2 grams of tabs per liter of cooling system capacity.

TIP: Cooling System Seal Tabs are packaged in two sizes.12378254 Small tabs (4 grams each) 5 tabs per package
3634621 Large tabs (10 grams each) 6 tabs per packageAccording to these figures, I have just added anywhere from 2-3 times the recommended amount during my recent coolant change. I wonder now if I need to drain half the coolant back out and replace with new Dexcool/Demin water without tabs to dilute the mixture before any damage is done!!!

krimson_cardnal
05-07-08, 02:22 AM
IMHO - no. If you added the recommended tabs to the upper or lower hose you're most likely in OK shape. Too much attention and concern is being applied to the issue. Again, it is only my opinion, Eric's post explains things in an updated way - great info to ease our minds and guide us in the future, however, he references 2004 GM Techlink. I have done the same as you with no ill effects what so ever. K_C

Ranger
05-07-08, 11:37 AM
Our old Guru said that it was almost impossible to put too many in....... unless you go crazy.

racinrod67
05-08-08, 01:11 AM
I'll leave it alone then, thanks guys.

08flstc
09-13-11, 09:52 AM
Okay, after reading all these posts, I'm STILL confused as to what the proper procedure is for my newly acquired 1987 DeVille? The car currently has "green" coolant in the system. Since I do no know the service history and the car has 88,000 miles on it, I want to make SURE that the coolant system is up to par, so the following questions come to mind...

1) Should I drain, flush and re-fill the system with a 50-50 mix of Dex-cool?
2) Should I add 3 or 6 of the GM tablets to the system?

The car runs great now and I want to do everything I can to keep it that way. Thanks in advance for your help.

Chris in PA
1987 Sedan DeVille

Submariner409
09-13-11, 09:56 AM
A 1987 engine is far removed from the general Northstar coolant/tablets/powder discussions.

Simply exchange your old coolant for a fresh fill of good ol' green 50/50 coolant and forget the tablet thing - if the cooling system has no leaks now, why risk clogging a heater core ?

tateos
09-15-11, 06:11 PM
Well, if you've already got conventional green coolant, whether it's an '87 or a '97, I would say drain and re-fill with green coolant and 3 tablets - they can do no harm, unless you add too many - then they can become too much of a good thing

00 Deville
09-17-11, 09:56 AM
Well, if you've already got conventional green coolant, whether it's an '87 or a '97, I would say drain and re-fill with green coolant and 3 tablets - they can do no harm, unless you add too many - then they can become too much of a good thing

I agree with you that the 08flstc should stay with the green coolant in his '87. I'm going to have to disagree with the use of the tablets... I wouldn't put the tablets in my car unless I was experiencing a leak that could not be easily fixed or diagnosed. I recently performed an autopsy on the surge tank on my 02 Deville and was amazed at the amount of sludge in the bottom of the tank. I highly suspect the sludge was from the seal tabs. The pictures can be seen in the thread below.

http://www.cadillacforums.com/forums/cadillac-deville-1985-2005-including-1985/230400-2000-2005-surge-tank-dissection.html