Coolant change - 2002 OBW

[srs_49]

I'm getting ready to change out the coolant in our 2002 OBW, 3.0L. I have the replacement coolant (Prestone, green). I was just planning on draining the existing coolant, running some water through the system while the engine is on to further flush things out, then add the new coolant, 50-50 mix. I have 2 questions:

1. Are there any additives I should use? I just replaced the coolant on my son's '94 Caddy Deville, and the Caddy forums called out using a Bar's Leak sealant, made from walnut shells, I think? Anything like that called for here?

2. Should I use distilled water?

 

Thanks,

[Setright]

3.0 liter engine shouldn't need any additives.

 

Yes, use distilled water, and 50/50 mix. You can tune the ratio, more water in hotter climates, or more antifreeze in colder climates. Always have 20% antifreeze, it's needed to lubricate the water pump and prevent corrosion.

 

And here's my tried and tested advice on re-filling copied from an other thread:

 

Having replaced coolant on my boxers many times, I have been searching for the right way to get all the old fluid out and getting as much new fluid in, without having to burp the system for a week after I'm done. I think I have finally cracked it!

 

Draining

 

Drain the radiator as far as possible with the little "faucett", and then detach the lower hose from the radiator. (If you are like me, replace any coolant hoses that you remove, and use stainless steel clamps on the new ones)

Even more fluid will drain from the radiator, and some will drain from the engine block. Detach the upper hose from the radiator, and run clean water through the rad until it comes out of the bottom clear in color.

 

Now, I do not contest that the best way to flush the engine block is by unscrewing the two drain plugs, but these are often seized and could turn into a source of trouble if you strip the threads or if they won't seal tight when you screw them back in. SO, I jack up the rear of the car until the engine block is tilting slight forward, ie. wheels about 6 inches off the ground, unscrew the thermostat housing, and let the old fluid run out through the thermostat opening. (Needless to say, I replace the thermostat gasket)

Run clean water in through the upper hose until clear water comes out of the thermostat opening. Leave the car in this position until it stops dripping water.

 

Remove the expansion tank and flush it, there will be plenty of "snot" in the bottom of it! Rinse the hose too. Install the tank again and fill to the FULL mark.

 

 

Filling

 

Close up the bottom end of the cooling system, ie. thermostat and lower hose. If possible, perform the next phase on a slight incline, car pointing upward.

Get a funnel with about 10 inches of half-inch diameter hose on the end of it and slide this down the upper hose in toward the engine block. I do this because bending the upper rad hose causes it to collapse and that makes pouring coolant into it impossible. Pour your preferred coolant directly into the engine block. Pouring slowly, and pausing along the way will help keep air from being trapped inside the block. It should swallow at about two litres before it starts to rise and threaten to come out of the hose. At that point, attach the upper hose to the rad and continue to fill slowly through the rad cap hole. Once it seems full, start the engine, let it run for twenty seconds and shut it off again. This will dislodge the few air pockets that are unavoidable and the fluid level in the radiator should drop a little after the burp, top it off.

Start the engine again, and let it run until the radiator fan starts running, be patient! When then fan starts running, top off the level in the rad and install the radiator cap - and bleed screw if there is one. During the warm up, a small amount of coolant will spill over the rad filler neck, have a cloth to absorb it.

 

Take the car for a shortish run, just a few miles to get it fully warmed up, and park it on level ground. Check hoses for leaks of course, and let it cool. This will take a number of hours, overnight is good.

In the morning, note the level in the expansion tank, it will probably be a little lower than FULL. Fill to the FULL mark, and you're all set.

 

Obviously, you should check the level in the expansion tank for a few days afterward, but there shouldn't be any problems. Resist the temptation to open the rad cap, this will only interfere

[unibrook]

Thx! I was wondering what the proven method was for changing coolant. Don't want to create the dreaded "air bubble" catastrophe.

Husk Fart Kontrol !

[crazyhorse001]

On the Caddy you changed the coolant in...If it's the northstar v8 & you put prestone green coolant in it, you can look forward to waterpump, & possibly even head gasket issues shortly. Caddy reccommends the dexcool for a reason, it has added lubricants.

[nipper]

On the Caddy you changed the coolant in...If it's the northstar v8 & you put prestone green coolant in it, you can look forward to waterpump, & possibly even head gasket issues shortly. Caddy reccommends the dexcool for a reason, it has added lubricants.

 

 

There have been a lot of issues with dexcool, with failed intake manifold gaskets.

 

http://www.consumeraffairs.com/automotive/gm_dexcool.html

Just search dexcool failures on google.

 

 

nipper

[srs_49]

On the Caddy you changed the coolant in...If it's the northstar v8 & you put prestone green coolant in it, you can look forward to waterpump, & possibly even head gasket issues shortly. Caddy reccommends the dexcool for a reason, it has added lubricants.

 

I spent a lot of time on the Cadillac forums before doing the coolant change. The consensus seemed to be that the "green" was fine so long as it was changed out evry 2 years and the sealant was used. Plus, the engine had "green" coolant in it, and I heard bad things about mixing green and DexCool.