LS1 pwrd NOVA

iTrader: (2)

What is causing my freeze plugs in my heads to deteriorate internally that they will start to leak coolant? First was my front pass side head a few years ago and now something is leaking again and it may be the driver rear head freeze plug as its dripping onto the exhaust. When I took off the the front freeze plug off of the passenger head, the inside looked like it was deteriorating slowly over time. Well something slowly ate the metal away and it finally starting leaking. The car had dexcool but since the leaks I've just been putting in distilled water. Is dexcool that bad to deteriorate metal? I thought even distilled water is ok to run as it has no inpurities that are bad. Now what sux is I may have to replace all the freeze plugs to eliminate any more issues. But I need to fix what is eating up the freeze pluge first or it may happen again over time. I am the second owner for about 10 years and do my own maintenance on the 99 ws6 and it only has 85000 miles on it.

senicalj4579

iTrader: (41)

You know, I know mechanics who swear that dexcool eats gaskets and parts. But at the same time I have owned 3 ls1 Camaros and I have no idea what they are talking about. I'v never had any of those issues.

I have never taken mine out I should do a cooling flush this year. Everything in my system (that I can see) looks good. I guess if there is any truth to the "deathcool" conspiracy time will tell lol.

dr_whigham

iTrader: (49)

I'd replace the plugs, flush the HELL out of the system, new hoses, Tstat, the whole 9 yards. Spend 200 and get a new water pump and an LT1 radiator.

And I'd stick with the Dex-Cool.

LS1 pwrd NOVA

iTrader: (2)

But...... what do you think is causing this issue though? I don't mind doing all that but I'd like to stop or fix what is doing this. Somethings not right as I only have 85k miles on this car.

dr_whigham

iTrader: (49)

Maybe at one time someone put something in the system they shouldn't have... Mixing green coolant with Dex, shitty water quality... Who knows. But obviously it needs to come out.

And if it's eating my freeze plugs, EVERYTHING associated with the cooling system is getting replaced.

RRW

Straight water, distilled or tap is not good either, it will cause the freeze plugs to rust out.

RockinWs6

Lots of misinformation in this thread. Best to read up on dexcool and dexclones like prestone. The problem is you **** getting air into the system somehow. its either a little low or has a small leak, air and dexcool = acid that wil eat the sheet out of everything. Dexcool-dexclones were designed to be used with CLEAN TAP WATER.

Drj8787

I agree with rockinws6 A few years back becuz of work I was doing on another car not my 98z but a gm truck long story short when dexcool is used with aluminum for some reason it cause electrolysis which is electric current flowing threw the water/coolant/liquid,when this happens the h20 is split down into seprate hydrogen and oxygen atoms which is how the air gets into the system. this is chemically breaking down the elements that are present where ever this takes place. So pretty much it's some bad sh** that u don't want to have in ur car! It eats way about anything it comes in contact with that's my .02

dr_whigham

iTrader: (49)

That's cute considering I'm the only one that replied.

Bottom line is no matter what the problem is, everything needs to be replaced. It doesn't really matter if the source is found or not, bc everything is trashed.

Grimes

iTrader: (3)

Don't want to start an anti-dexcool flame war over here, but if you have a properly sealed system, with 50/50 clean water and dexcool, you should be fine. Running straight tap water is not a great idea because you are then lacking any rust inhibitors and other additives that are good for the cooling system.

Been running dexcool and water for over 12 years now, and have been doing amazingly well. My radiator rusted out from road salt, but when I removed it, the interior was perfect.

CattleAc

iTrader: (7)

This is it...I have 7 different vehicles with DexCool. Six are well sealed and have been just fine...the other one developed a small leak about half way down the radiator. I kept just adding to the over flow tank for a couple years...what a mess. The whole system is a nightmare of corrosion inside.

joecar

The problem (even if you replace the coolant) may be due to coolant completing the electrical path to ground (check for missing ground connections)...

you can test this by seeing if liquid coolant in radiator has an offset voltage compared to battery/vehicle grounds (test with engine running).

Drj8787

Aluminum doesn't rust lol it oxidizes to Al2O3. When aluminum oxidizes the surface layer of material becomes hardened. Passivation is a way of oxidizing and hardening the outer most layer of material on lots of material like stainless steel, defferent hastelloies, aluminum, ect...Which actually makes it stronger. Anidoizing is passivation FYI with dye interduced during the process. So you saying ur radiator rusted out is and oxymoron lol it didn't rust the electrolysis has ate the material away it dissolved it essential

Drj8787

I'm not saying dexcool doesn't work or can't be used for 12-15 years but 16 yrs I'd be weary. It was a real big prob with head and intake gaskets on 97 and 98 ls motors and the genII vortec truck motors 96+ just say its very common prob with anything that had dexcool in it

Grimes

iTrader: (3)

Well "rust" is a general not totally accurate term, I agree. But if you want to say aluminum oxidizes, then you can also say that something containing iron oxidizes to form "rust".

Either way, my radiator failure was not caused by dexcool, it separated and peeled apart due to the electrolytic process you speak of, from the outside, not interior.

Also, I refreshed my coolant every spring by draining just the radiator.

LS1 pwrd NOVA

iTrader: (2)

So many variables but lots of good info from all.
I can understand that low coolant and air may cause an issue, but initially, the only leak I had was from the freeze plug deteriorating. So if I was a little low on coolant, which I can't recall over all these years would that make the plug fail? Electrolysis makes sense or some form of catholic protection is needed it seems to protect the dissimilar metals, aluminum head and steal or stainless freeze plugs. Maybe I have a ground missing on the block as stated earlier.

Drj8787

Typically if a ground is missing some where it won't start on these cars. Had this prob before took forever to fig out it was a ground that didn't get hooked back up behind the intake up under the fire wall

Jeff Smith

iTrader: (44)

My ls2 Camaro's 243 head (3) freeze plugs fell out recently. I use distilled water. Next time I will use dex-cool.

A.R. Shale Targa

iTrader: (2)

GM created Dexcool to be able to sell to customers the "idea" that their cooling systems were 100,000 mile maintenance free. The problem is as some of the chemists have stated that the relentless heating/cooling cycles does in fact change the Ph balance of the Dexcool...essentially changing it to acidic which again as others have declared eats the **** out of gaskets, plugs, radiatiors, and thermostats. Those who spend the money, invest the time, and MAINTAIN their cooling sytems will almost never have any issues with Dexcool.

64post

iTrader: (5)

Why not run a radiator cap with an anode under it? (available at Summit, Jegs etc..) it will be consumed first by the electrical charge introduced into the cooling system. There are different theories as to why this happens ( charged coolant) but it's much more common than most people think. Use a DVOM and you can actually read voltage in your cooling system.