Antifreeze leak... just need a step by step.

[Nitro187]

I believe my head-gasket is leaking antifreeze. Lots of fun. I have a 99 Grand AM GT, and was curious if anyone has a step by step, or a how to on changing a head-gasket? Just so I don't buy a headgasket, and then change it.. just to find out I should have changed something else at the same time; for example, should I do the intake manifold at the same time? What about Valve covers? The head gaskets are running about $35 each, so not too bad.

I had a 96 Grand am GT before this, and it was rather simple, but this is a different engine completely.

Thanks!

[crazy Jim]

Whenever I take an engine apart I replace every gasket, O ring, rubber hose and belt because usually by the time you are tearing into an engine the car is many years old and the harsh enviroment of an engine compartment deteriorates these items fairly quickly. I also change the spark plugs and wires (on really old engines; distributor cap, rotor, capacitor and points) engine oil and filter. On really high mileage vehicles I replace/rebuild the Altenator and Power steering pumps as well.

[xeroinfinity]

Its not that bad to change the head gaskets, but you really need a manual of some sort, to many things to remember.
I dont know of any free online help either for the 99' and up.
Even a cheap haynes manual will help.

But Why do you think the head gaskets are bad;
Do you have overheating,
coolant in the oil,
oil in the coolant.
Or Just leaking out onto the ground?

BWT,
I do Have a copy of the revised lower intake procedures from 2003, which wouldnt be in a manual unless it was made after 2003.

Engine Oil or Coolant Leak (Install New Intake
Manifold Gasket) # 03-06-01-010B - (10/24/2003)


Engine Oil or Coolant Leak (Install New Intake Manifold Gasket)

2000-2003 Buick Century

2002-2003 Buick Rendezvous

1996 Chevrolet Lumina APV

1997-2003 Chevrolet Venture

1999-2001 Chevrolet Lumina

1999-2003 Chevrolet Malibu, Monte Carlo

2000-2003 Chevrolet Impala

1996-2003 Oldsmobile Silhouette

1999 Oldsmobile Cutlass

1999-2003 Oldsmobile Alero

1996-1999 Pontiac Trans Sport

1999-2003 Pontiac Grand Am, Montana

2000-2003 Pontiac Grand Prix

2001-2003 Pontiac Aztek

with 3.1L or 3.4L V-6 Engine (VINs J, E - RPOs LG8, LA1)

This bulletin is being revised to change the model Information. Please discard Corporate Bulletin Number 03-06-01-O10A (Section 06 - Engine).


Condition

Some owners may comment on an apparent oil or coolant leak. Additionally, the comments may range from spots on the driveway to having to add fluids.

Cause

Intake manifold may be leaking allowing coolant, oil or both to leak from the engine.

Correction

Install a new design intake manifold gasket. The material used in the gasket has been changed in order to improve the sealing qualities of the gasket. When replacing the gasket, the intake manifold bolts must also be replaced and torqued to a revised specification. The new bolts will come with a pre-applied threadlocker on them.

Notice

An oil leak may result if the vertical bolts are not tightened before the diagonal bolts.


Diagonal bolts may require a crows foot to tighten.

Tighten

1. Tighten the vertical lower intake manifold bolts (1) to 7 N.m (62 lb in).

2. Tighten the diagonal lower intake manifold bolts (2) to 7 N.m (62 lb in).

3. Tighten the vertical lower intake manifold bolts (1) to 13 N.m (115 lb in).

4. Tighten the diagonal lower intake manifold bolts (2) to 25 N.m (18 lb ft).

Lastly I would replace all the gaskets.
You will also need new head bolts.
The ones you take out will be stretched and no good.
And Fel Pro gaskets are really good!

Hope that Helps &
Have a Happy New Year!

[Nitro187]

It might not be my head gasket a mechanic told me, but he said it's like an 8 to 10 hour job to replace the "panel gasket? or pan gasket?" I forget which he said, but either way... no oil in my coolant, and no coolant in my oil. It's just leaking onto a peice in the middle of my engine, then evaporating, causing a very sweet smell (the antifreeze) I go through a gallon jug a week from topping it up, it's becoming expensive, and annoying.

How long would it normally take to replace all the gaskets on an engine? Anyone know? Is it a job I could do myself, or leave it to the pros? Would it require me taking the whole engine out?

[crazy Jim]

Eight hours for pro may be stretching it, for a novice it may take twice that long. Quite a bit has to be removed to get the lower intake manifold off. No need to pull the engine though and you just need to replace the upper and lower intake manifold gaskets and the odd O ring or two that comes in the kit.

[xeroinfinity]

Well just removing the Lower intake will be between 8-12 hrs depending on previous experiance with this engine.

To do all the gaskets, hum thats a weekend job for sure.
If you have a good shop manual, and have to tools and a place to tear it down you can DIY .
And take notes or pictures , they are great referance.

The motor doesnt need removed for this.
Just alot of time and patients.