: Where does a coolant change go into?



Jack M
02-23-05, 11:44 PM
I drained and filled my '85 Eldo radiator with 50/50 Prestone, plus sealant tabs, a month ago, and decided today to do the same with my '01 Eldo ETC. Then, the fun begins:

I couldn't find a radiator drain cock, then I couldn't find a radiator cap and neck. I got my operator manual out and only saw reference to topping off the Dex-Cool via the surge tank, and putting the tabs in the radiator hose. Nothing about draining and refilling the radiator, like a gallon or so.

So, I conclude either I'm a dumb-ass, or only the dealership can do what I intended, or both.

The Dex-Cool reference wasn't a complete surprise, since the car is a 2001 model. But I bought the car from a dealer when it had 16k miles on it (22k now), and don't really know it's anti-freeze history, so wanted to hedge all bets by changing coolant. Then I got my two above surprises!

So, you 200x Eldo and Seville owners out there - is there a drain cock and a radiator cap/neck somewhere on my car? If not, how does a dealership change coolant? Or, do they assume that Dex-Cool equiped cars only have to be toped-off through the surge tank, and owners have no need for the more traditional means changing coolant? Also, is there a test to determine if I truly have Dex-Cool coolant in my cooling system?

Help!! Jack M.

Ranger
02-23-05, 11:56 PM
There is a drain plug. Usually at the bottom left (driver) side of the radiator. Also usually impossible to reach. It is easier to just remove a radiator hose and let it drain. You need to put the tabs in the hose anyway. There is no radiator cap. fill slowly though the surge tank. The Northstr is self purging so after the fill warm it up and run the RPM up to 3000 or so (or take it for a ride) to purge the air if any is in the system then recheck the level. Dex-Cool will be orange as opposed to conventional green coolant.

BeelzeBob
02-24-05, 12:01 AM
I drained and filled my '85 Eldo radiator with 50/50 Prestone, plus sealant tabs, a month ago, and decided today to do the same with my '01 Eldo ETC. Then, the fun begins:

I couldn't find a radiator drain cock, then I couldn't find a radiator cap and neck. I got my operator manual out and only saw reference to topping off the Dex-Cool via the surge tank, and putting the tabs in the radiator hose. Nothing about draining and refilling the radiator, like a gallon or so.

So, I conclude either I'm a dumb-ass, or only the dealership can do what I intended, or both.

The Dex-Cool reference wasn't a complete surprise, since the car is a 2001 model. But I bought the car from a dealer when it had 16k miles on it (22k now), and don't really know it's anti-freeze history, so wanted to hedge all bets by changing coolant. Then I got my two above surprises!

So, you 200x Eldo and Seville owners out there - is there a drain cock and a radiator cap/neck somewhere on my car? If not, how does a dealership change coolant? Or, do they assume that Dex-Cool equiped cars only have to be toped-off through the surge tank, and owners have no need for the more traditional means changing coolant? Also, is there a test to determine if I truly have Dex-Cool coolant in my cooling system?

Help!! Jack M.


DexCool is orange....conventional silicated coolants are green. Look at the color.

The Northstar cooling system has the pressure cap on the pressurized surge tank....not the radiator. The surge tank is an active part of the cooling system not just a coolant recovery bottle like the 85 Eldo with the 4.1 has. Fill the system thru the pressure cap fitting on the surge tank just like it was on the radiator.

There is a drain petcock on the lower edge of the left hand tank I believe.... Honestly, it is easier to pop the radiator hose off and drain the system that way for several reasons. It is easier to get to. It drains faster. You need to disconnect one of the radiator hoses anyway to install the GM Coolant Supplement pellets into the hose. Use the Supplement with the Northstar but do NOT install it into the surge tank as it will not distribute thru the system.

When you drain the sytem and install the coolant supplement pellets into the hose and reconnect it just refill the system thru the surge tank cap fitting. Pour slowly and the system will fill fine. When the system is full and the coolant backs up into the tank start the engine with the cap off, rev it slowly to 4000 RPM or so and back to idle several times to purge any air out. Turn the engine off and top off the surge tank with coolant until it is about 1.5 or 2 inches from the cap fitting. Install the cap and you are done.

Make sure you use the DexCool mixed 50/50 with distilled water. The OEM supplier of the DexCool is Texaco if you can find their product in a store then you have the OEM stuff.

Jack M
02-25-05, 05:55 PM
Thanks for the help, guys. Hopefully I'll be able to see some orange color in the surge tank, then top it off with 50/50 DexCool, as necessary.

The '01 car is 4 years old, but has only 22k miles on it. I read someplace that DexCool lasts a long time (80k - 100k miles, or 8 - 10 years?), so I'll have a while before a drain-out procedure, like 60,000 miles/4 years from now.

However, with respect to the 3 - 6 sealant tabs, is there a mileage or age thresh hold that I'll need to drain the existing DexCool in order to place the tabs in the lower radiator hose and refill? Big Question.

Other questions: How about water pump lubricant? And thermostat replacement? I'd probably have the dealer do this latter item. But when?

My retiree driving habits are mostly to the golf course and a few errands two or three times a week, so don't put many miles on the car, particularly since buying the '85 Eldo, which needs it's turn, too. I'd guess 4k miles/year on the '01, and 2k miles/year on the '85.

Thanks again for the help, and you patience! Jack M.

Ranger
02-25-05, 11:10 PM
Dex-Cool is 5 yrs or 150K but personally I'd error on the safe side and go 4 yrs at most. Replenish the tabs every time you do a coolant change. The coolant contains all the lubricant you need. I wouldn't worry about the stat til it gives you a problem or maybe at 100K. Mine is still OEM at 97K.

Yaemish
02-28-05, 03:56 PM
I tried changing the coolant in my Eldorado the other day. I'm not really seeing where I can disconnect the radiator hose. How close the the clamp to the radiator? I don't want to break anything when I do this. Also, I got Alumiseal brand powder, will this work instead of the Bars Leak stuff?

davesdeville
02-28-05, 04:58 PM
The radiator hoses run between the radiator and the engine and have regular, worm gear type hose clamps. Alumaseal will NOT work!

oldgamer
02-28-05, 05:27 PM
...The '01 car is 4 years old, but has only 22k miles on it. I read someplace that DexCool lasts a long time (80k - 100k miles, or 8 - 10 years?), so I'll have a while before a drain-out procedure, like 60,000 miles/4 years from now.

However, with respect to the 3 - 6 sealant tabs, is there a mileage or age thresh hold that I'll need to drain the existing DexCool in order to place the tabs in the lower radiator hose and refill? Big Question.

Other questions: How about water pump lubricant? And thermostat replacement? I'd probably have the dealer do this latter item. But when?
...

It's looks like about time to change coolant (Dexcool works for 5 years or 100K). So, just drain and refill (NO FLASH!) with Dexcool and sealant tabs.
Don't warry about water pump and thermostat. My car is 11 years old and still has original water pump and thermostat. If it works don't bother to change it. The dealer can't do anything good for your car but broke at most cases, don't change anything in the car untill it's a nessesary.