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3400 gm engine burning water,

10K views 11 replies 7 participants last post by  fast68 
#1 · (Edited)
got a 2000 something 3400 grand prix

burning water gettin hot

tryin to make sure its a head gasket blown

when the thermostat opens big large bubble of air come up out of the coolant tank every few seconds or so

from my past experience with bown head gaskets this means one or both are blown.

and it is not an intake gasket, in which would not force air bubbles up through the tank


correct?

any good tips to help tearing the heads off a 3400 engine easier or quicker let me know please

what is book time on both head gaskets on one of these things?




thanks
randy
 
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#2 ·
fast68 said:
got a 2000 something 3400 grand prix

burning water gettin hot

tryin to make sure its a head gasket blown

when the thermostat opens big large bubble of air come up out of the coolant tank every few seconds or so

from my past experience with bown head gaskets this means one or both are blown.

and it is not an intake gasket, in which would not force air bubbles up through the tank


correct?

any good tips to help tearing the heads off a 3400 engine easier or quicker let me know please

what is book time on both head gaskets on one of these things?




thanks
randy
Head gaskets are not common on those. Intakes are real common. I would do a compression test before you go pulling heads off. Those dexcool engines will eat the intake gaskets.

As far as doing head gaskets, I have done a couple, both had been overheated and the job wasn't bad. a couple things if you are just doing the intake, you need to keep the push rods in order. They are not all the same length. The rear valve cover is a pita to get off. We leave it and use a tool to get the rockers off the push rods. It is something that we made. You can also back off the nuts without taking the cover off if you want.
The rear head is also a pita to remove. Be careful when you lift the injector rail out. Try not to remove the injectors from the rail. On most of them you dont need to disconnect the fuel lines. you can just flop the whole thing out of the way
 
#3 ·
I do MANY of these per week. We joke all the time about these heads being a great bread and butter Generous Motors item. I do so many that I have one machine dedicated to these heads..

Once the intake gasket goes. The engine warps the end cylinders. Heads usually rise .003-.005" on the ends of both. The inside (rear) head is usually the worst. DO BOTH HEADS!!!

Only cure is to mill heads usually .005" Don't let it go too long or you will pay "Mucho dinero" for the consequences..


You will also find at least two flush broken exhaust studs in the heads when removed. They can be real fun to remove/re-tap
 
#4 ·
And when you put it back together, after blasting any and all traces of DexCool from the thing, refill it with something green, like Prestone, and if you just gotta follow directions and use water--- use distilled water.

Another option if your back pocket wad is up to it, is Peak. This stuff is made out of the same things found as a preservative in food,,,? Propylene glycol! Which is easier on pets, stupid kids and the environment. Again if you just have to put water in the mix use distilled.

Numeral uno is Evans, but bring your rich uncle and some nitro pills along.

Bogie
 
#5 ·
A trick to help get to the rear head area easier is to remove the dogbone mount(the one going from the engine to the front of the car on top)have some one set in the car with it in park, push back on the car the engine will rotate forward then set the park brake and chock the wheels.This makes accessing the bolts, valve cover etc. much easier.
 
#7 ·
BOBCRMAN@aol.com said:
I do MANY of these per week. We joke all the time about these heads being a great bread and butter Generous Motors item. I do so many that I have one machine dedicated to these heads..

Once the intake gasket goes. The engine warps the end cylinders. Heads usually rise .003-.005" on the ends of both. The inside (rear) head is usually the worst. DO BOTH HEADS!!!

Only cure is to mill heads usually .005" Don't let it go too long or you will pay "Mucho dinero" for the consequences..


You will also find at least two flush broken exhaust studs in the heads when removed. They can be real fun to remove/re-tap
How does the intake gasket going bad warp the heads. This makes no sense unless the car was overheated. If overheating is in the equation then anything is possible.
We have done 100's of intake gaskets that have not resulted in head issues. Am I missing something.
 
#8 ·
The intake gasket deteriorates from design and Dexcool coolant problems.

The typical car owner doesn't notice anything wrong till the cars warning light comes on or the driver actually looks at any guage other than the fuel level. In Michigan they seem to notice the heater quits working before seeing any other sources..Either way and the engine is cooked..

Replacing the intake gasket is a temporary fix at best most of the time. If the vehicle has over 120 thousand miles on it. The heads are well on the way to failure.

Once overheated the head bolts relax just that small amount. The head gaskets start brinnelling the aluminum heads and very soon the compression overtakes the metal fire ring on the outer upper edges of the gasket.

Coolant in cylinder. Pour in stop leak..... Next is coolant in oil...More stop leak... Then rod knocks, or cam bearings seize or cam breaks==== Adios !!!
 
#9 ·
done, fired right up purrs like brand new,. wow so nice now.

good info to learn here thanks :)

car just left here with its happy owner.

its a gt with ram air and from canada.

it drives absolutely like a brand new car, so effortlessly wow, it doesnt even feel or drive like a typical grand am... at all..

must have some kind of chassis stabilizers or somethin extra hmm.. and also better brakes and better steering than typical ones because wow they all work so awesome... ive never felt a grand am like this, driving it,.,.




wow.
 
#10 ·
BOBCRMAN@aol.com said:
The intake gasket deteriorates from design and Dexcool coolant problems.

The typical car owner doesn't notice anything wrong till the cars warning light comes on or the driver actually looks at any guage other than the fuel level. In Michigan they seem to notice the heater quits working before seeing any other sources..Either way and the engine is cooked..

Replacing the intake gasket is a temporary fix at best most of the time. If the vehicle has over 120 thousand miles on it. The heads are well on the way to failure.

Once overheated the head bolts relax just that small amount. The head gaskets start brinnelling the aluminum heads and very soon the compression overtakes the metal fire ring on the outer upper edges of the gasket.

Coolant in cylinder. Pour in stop leak..... Next is coolant in oil...More stop leak... Then rod knocks, or cam bearings seize or cam breaks==== Adios !!!
I agree if overheated and aluminum head engine is in trouble. I guess we have been lucky and have caught them all early enough.
We recently had one with a cam shaft that broke in half.
 
#11 ·
fast68 said:
it drives absolutely like a brand new car, so effortlessly wow, it doesnt even feel or drive like a typical grand am... at all..

must have some kind of chassis stabilizers or somethin extra hmm.. and also better brakes and better steering than typical ones because wow they all work so awesome... ive never felt a grand am like this, driving it,.,.




wow.
I think they're the same... us/can market for the most part, maybe metric gauges for Canada. The GT has a firmer suspension, thicker sway bars, 4 wheel disc brakes, and wider tires than the standard 'se' version.

The Ram Air is kind of a gimmick, look at how it pinches down and twists around to the airbox, then there's this other air intake at the airbox that goes to the front fender (the only intake for the SE models). There goes any ram air pressure :( I had a 'cold air intake' that ran down behind the drivers side fog light; had to pull the plugs for the inner fender liner to clean the KN filter. But it ran like hell with that and a 2.5" exhaust (mandrel is best, 'pressure bent' is ok where the inner radius of a turn goes in a little, but the 'crush bent' ripples on the inner radius of a bend is to be avoided!)... considering the effort I put into it and starting off with 170hp.

check out gaownersclub.com as there's guys there who did simpler mods like me, and guys who are doing more hardcore stuff.
 
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