GormanRacingZ28

I have a 2002 Camaro Z28, i'm the second owner and it just it 70k miles, decided that it was time for a coolant change and discovered nice green coolant, went to work and got 2 bottles of Dexcool. I have been having minor overheating issues ever since I changed the valley cover gasket, I know that I exposed the system to air and I think I might have some within the system. Q1 What is the best way to relieve air from the system and what is the complete procedure. Q2 How do I know if the air is removed? Thanks. Never done it without a machine so I figured I could learn on LS1tech from you guys.

dr_whigham

iTrader: (49)

I'll tell you the "Whigham Method" which I'm sure alot here may be opposed to....

Once its topped off, with the cap off, start her and while she's getting to operating temp, squeeze the top coolant hose trying to expell all the air you can.

If it holds operating temp no problem, take the car out and beat on it. Think high RPM here. That should definitely circulate out any other air.

This method has never failed me.

Personally, I think your issue is a mixture of green coolant with Dex. That WILL create blobs, so to speak, as when they come in contact with one another they coagulate.

Here's my question: when you "drained" the green coolant, did you drain the block as well?

GormanRacingZ28

Thank alot man, I'll do that now and give it a shot. I put straight distilled water into the system and let it run till it hit operating temperature, just to extract any green coolant within the system. I did this about 4 times till I saw nothing but pure water coming from the drain plug on the radiator.

RezinTexas

you MUST drain the block, otherwise you will NOT get out all the old coolant.

Lambert695

iTrader: (17)

I would have never put dexcool back in it, im sure many people disagree with me but dexcool is junk

dr_whigham

iTrader: (49)

Oh, I agree. The only, and I mean the ONLY reason I have Dex is exactly this reason. It's hard to get EVERYTHING out to make the switch.

I think Dex is good for a completely sealed system. Ours isn't completely sealed though, hence the issues.

I know the Dex in the Escalade is just as orange as the day I bought it. Sealed system.....

GormanRacingZ28

I drained the entire block from the drain plug, added the new dex till it reached the bottom of the filler neck, started it up and watched it bubble for like 4 mins, squeezed upper hose until it stopped bubbling, then turned it off and the coolant level started dropping. Added more coolant and went for a test drive. here is the shitty part, not even 3 miles down the road temp almost hit 260. Pulled over till it got around 210 and drove back. Not sure if I still have air in the system.

dr_whigham

iTrader: (49)

Did you flog the car? To get the air out you have to drive HARD. The water pump is belt driven.... RPM dependent....

GNIUS

iTrader: (2)

Open the cap. Turn on the the engine then fill it to the brim then close the cap. This will get all they air out of your system.

GormanRacingZ28

@Wigham, I drove it hard and it is a little bit better but not much. Gonna let it cool down, pull the cap and run the engine. This tumor of air is pissing me off.lol.

chrisfrost

iTrader: (8)

You can drive car on a really steep place ,,,,,,,or use a vacuum pump for A/C and with system empty pull a vacuum , then let the vacuum pull the coolant in until as full as You can get ,,,,,,almost full but less air than pouring it in at no pressure ,,,,then do 1 of the previously described procedures .

joecar

You can get air out by undoing the hose that comes from the steam crossover tube (immediately to the lower right as you look at the front of your throttle body)...

if you undo this hose, and place a length of clear tube on the steam crossover outlet, you can watch air bubbles coming out... when the air is gone (you may have to give the engine an occasional rev every so often), the clear tube will show only coolant; keep an eye on the temp gauge, it shouldn't go above 220F.

You might want to first fill the block by pouring coolant in thru the upper radiator hose (with the steam crossover hose undone).

chrisfrost

iTrader: (8)

Don't You have the cross over tubes ,,,,,,,,if so just crack the bolt loose with the cap closed and the air will bleed out until coolant comes out then tighten bolt .

GormanRacingZ28

I just performed everything that everyone has said, and no overheating exist. Thanks alot guys, 10 mins of bubbles = orgy of excitement.lol. Stays below 210 where it used to be. Didn't think that exposing the system in such a small component such as the TB could cause all of this. Thanks again.

02 NHRA

So when you guys say "cross over tube" I'm guessing that is the throttle body coolant hoses? I am dealing with the same problem and haven't tried this or filling the block through the upper hose yet.

GormanRacingZ28

Well I ******* spoke to early. Now it wants to make gargling noises. I don't think my baby has burped every last bubble up yet. Gargling means air in the system right, only does it when I turn the car off. Damn guys thought this was it. 02 NHRA, yeah those are the crossover tubes, connect to the cylinder heads and have a hose feeding the Y. This is a pain in the *** man.

bww3588

iTrader: (49)

There is nothing wrong with dexcool. Sealed system or not. It goes bad when people mix it with plain tap water or other coolants. Like the idiots at quick lubes that just "top it off" with whatever happens to come out of the hose labeled "coolant"

Lambert695

iTrader: (17)

Still going to have to go with the fact that dexcool is junk, and will have to disagree with your "top it off" thing. Dexcool might be ok at first but when it goes bad.... it goes bad fast. Leaving you with crap colored clumps passing through your engine.

bww3588

iTrader: (49)

"when it goes bad" is the key phrase there. do you even know why it goes bad? and its not because of air in the system...the reason it goes bad, and only reason is being mixed with things that are not compatiable with dex. i.e. plain water, green coolant, ****, beer...etc

I'm sorry, but over 20 years of GM vehicles in my family and having dexcool equipped vehicles since it has came out and not a single problem with any of them is proof enough for me. your going to have to do a lot to convince me and a lot of other people on here that it is junk.

I'm sure you will have the bandwagoners jump on board with you that neglected their system and had problems...but again, dexcool doesnt just go bad on it's own.

91sonomast

Not correct, when I worked for GM doing GM training we got on the topic of dex-cool, and the engineers said dex-cool needs to stay away from air, I asked why they used it in open systems. "Well it's cheaper for GM to use one coolant than 2-3 different kinds so every vehicle get the same thing. In all actuality if you have a vehicle with a non-sealed cooling system, every 50,000 miles the dex-cool either needs to be fully flushed or the better option, with the first 50k clean the cooling system completely of dex-cool and switch to green and go 150k miles with no worries." And how many dealerships use distilled water? It is specifically stated to use distilled water with dex-cool if you read GM's actual recommendations. In a sealed system, dex-cool is fine as long as you use distilled water only and keep the system sealed up. But if you have a leak, you are supposed to drain the system and refill with fresh new dex-cool because it has been exposed to air for an extended period. I have more faith in green, it is less aggressive and less corrosive to aluminum, laboratory tested and proven time after time. No one really knows why GM spent all that money to design dex-cool and still uses it, it's mostly junk. It needs to be flushed every 50k sealed system or not, you can run it longer than that and risk it, but I wouldn't. When it goes bad, it only takes a few weeks for dex-cool to get ugly and do damage.