1fine69

Hey guys,

I've got this 98 LS1/T56 combo with 42,000 miles in my '69 Camaro, and it just started smoking white and dripping a LITTLE antifreeze out of both tailpipes. I had a friend following me probably 2 months ago and he said it was putting out some smoke on WOT. The car has a good radiator/fan combo and a 160 degree thermostat, so it's NEVER gotten over about 190.

I haven't been driving it much lately, probably 50 miles in the last month, but I started it last night and let it idle for about 5 minutes, and then was revving it up to ~3k RPM's when I noticed. I was trying to get it to throw a CEL(it does every once in awhile) so I could pull the codes.

Is there any chance it's anything other than a headgasket? I'll be doing a leakdown test soon, but I'm a a little worried, seeing as how it's coming from both sides, and how likely are 2 headgaskets to pop at the same time?

Little background - the motor that's in the car came out of a 98 Z28 that was hit pretty hard in the front passenger's side(totaled), and I've already had to replace the water pump and alternator as they went out - the motor sat, unstarted, for 4 years while I scrounged up the time and money to finish the swap. The motor seemed to run fine when I pulled it out of the car...

Thanks again guys,
-Adam

jam01

thats a real nice looking car. any thing is possble with engines, is there water or coolant in the oil? any leaks or cracks on the block, did you change the intake manifold. i dont think there is a magical answer except doing the obvious test's to see whats wrong. you could try pressurizing the coolant system to see if any leaks out.

conan

iTrader: (5)

Sound hike a head gasket to me. Do you have a (H) or a (X) pipe in your exhaust system? If so its probly just one and its mixing in the exhaust system. If it were me I'd pull both heads and replace both gaskets. Nice car BTW! got any pic's of the ls1 under hood?

Wesmanw02

iTrader: (4)

I think that 4 years of sitting is probably what did the head gaskets in. Dexcool has a tendancy to eat through gaskets when left in an engine for too long, and having that coolant sitting in the heads for 4 years is like leaving acid in the motor. Its going to chew up gaskets, you should see what my 3800 Series II looked like after 10 years of Dexcool.

I would change both head gaskets with GM OEM MLS gaskets, and any other gaskets that appear to be worn or leaking in the process. I assume you're not going to pull the motor, its much easier to work on an LS1 in a 1st gen than a 4th gen.

When you refill the coolant, flush the system with a flush kit and garden hose, and then refill it with the newer Prestone or Peak All Makes/All Models 50/50 Coolant. Its compatible with all antifreeze, and they use distilled water in the 50/50 blend to prevent corrosion from minerals and conatminants found in regular water. Then you should be good to go.

Might want to also consider a heads/cam swap while you have the whole thing apart, you can pick up a set of LS6 heads and an LS6 cam for pretty cheap these days and still retain stock driveability while adding about 60WHP.

CoastieWS6

iTrader: (1)

So it's better to switch to prestone? Also how many people have done this?

Wesmanw02

iTrader: (4)

Yes. As for the amount of people that have done it...countless, its not a big deal because the new ALL MAKES/ALL MODELS coolant is compatible with both conventional green antifreeze as well as Dexcool...so there is no downside to switching, nothing will be damaged, and you can even add it without a complete flush. Its just better coolant, it has the long life additives of dex-cool with the gasket and metal friendly properties of the conventional green antifreeze.

Wesmanw02

iTrader: (4)

Here's what my '97 GTP looked like when I pulled the intake after 10 years of Dexcool (I highly doubt it was ever changed/flushed):

CoastieWS6

iTrader: (1)

Holly sh%t! Ok, note to self change coolant

Vndcatr

iTrader: (8)

Well on my next self service, Ill definally note to switch coolants. But ive drained my coolant completely about 3 times from cam swaps and a water pump!..

Wesmanw02

iTrader: (4)

From what I've seen, Dexcool really isn't a problem is its changed often as you've been doing. But when its left in the cooling system for many years/100K miles, it starts to eat through gaskets. So with proper cooling system maintanence you should never have a problem, but I'd rather run the universal green just to be on the safe side.

1fine69

Hey guys,

The motor was DRY when it was sitting for so long, so I don't know if Dexcool could eat it up like that - it was in probably 0 degree temps for 10 days, so who knows what could have happened...I'm pulling the throttle body and plugs tomorrow to see if there's antifreeze in the intake and what chambers have it.

And to answer another question - this car has NO crossover. The right header comes out the right tailpipe, and left out the left.

Thanks for the advice,
-Adam

Wesmanw02

iTrader: (4)

Thats good that it wasn't full of coolant, but that doesn't mean that there wasn't any left in the coolant passages in the heads/block, which could still east away at gaskets, especially when exposed to oxygen, which might make it worse.

Bottom line is it sounds like you have bad head gaskets, you can do a cooling system pressure test to confirm that though.

jam01

thats not just from not servicing the cooling system, looks like lack of any kind of servicing.

Old Geezer

iTrader: (3)

X2...
no oil change for 10 yrs!!

Wesmanw02

iTrader: (4)

Well I bought the car when it had 152K miles so who knows its past service history. It appears that regular oil changes were done, but probably not every 3,000 miles, and they definitely used cheap oil, because every part that was replaced or serviced on the car was from Autozone. So I'm sure that included Autozone Valuecrap oil or whatever it is as well. The Supercharged 3800 Series II run hot by design, which is the reason that the oil is sludged up everywhere and burned onto everything, it was the same deal when I changed the valve cover gaskets. Let that be a lesson as to why running cheap garbage oil in a high performance motor is a bad idea, no matter how much you change it you can't avoid the effects that thermal breakdown has on conventional oil over the oil change interval. The reason the stock intake gaskets break down is also from the heat, stock gaskets are plastic, and sit between an aluminum supercharger and lower intake. So they end up eventually melting and turning into brittle plastic that leaks. The replacements from GM were soft aluminum gaskets, which are supposed to be much better.

As for Dexcool, you can see where it began eating through the gasket around the coolant passages. If left in an engine too long it tends to become corrosive.

BlueBird346

iTrader: (13)

Off topic, but thats a badass car.

SMAX

iTrader: (11)

You really shouldn't find any coolant in the intake because no coolant passes through the intake. I would pull the intake off and then just go ahead and pull the heads. It sounds like bad head gaskets. Go to a GM parts dealer and get a set of head gaskets for a 2004 gto then pick up a can of copper gasket spray from the parts store, and you are also going to need a new set of head bolts either factory or step it up to a set of ARP's which are reusable.