GM 3.4L intake gaskets

[88Nightmare]

How hard of a job is this? I have to get it done on a friends car. Anyone have any tips or tricks for this job?

[Lash]

Upper...or lower intake gasket....or both?


Use good gaskets otherwise you'll be doing it again in no time.

[Holeshot]

Document ID# 209819
1998 Pontiac Grand Am

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Intake Manifold Replacement Lower
Removal Procedure

Caution
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.


Disconnect the negative battery cable.
Depressurize the fuel system. Refer to Fuel Pressure Relief Procedure in Engine Controls - 3.1L.
Remove the top half of the air cleaner assembly.
Drain and recover the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.



Remove the EGR pipe from the exhaust manifold.
Remove the drive belt. Refer to Drive Belt Replacement .
Remove the brake vacuum pipe at the plenum.
Remove the power steering lines at the generator bracket.
Remove the generator. Refer to Generator Replacement in Engine Electrical.



Remove the secondary ignition wires from the spark plugs.
Remove the secondary ignition wires from the harness at the plenum.



Remove the following components at the same time:
Electronic ignition coil and module assembly
EVAP canister purge solenoid
Remove the following upper engine wiring connectors:
Throttle Position (TP) sensor
IAC sensor
Injector harness
Engine Coolant Temperature (ECT) sensor
MAP sensor
Camshaft Position (CMP) sensor




Remove the following vacuum lines:
Vacuum Modulator
Fuel Pressure Regulator
PCV




Remove the MAP sensor from the upper intake manifold.



Remove the upper intake manifold bolts.
Remove the upper intake manifold.



Remove the fuel lines at the fuel rail and the bracket.
Install the J 28467-360 .
Remove the engine mount assembly. Refer to Engine Mount Replacement .
Remove the power steering mounting bolts. Support the pump aside. Refer to Power Steering Pump Replacement in Pwer Steering System.



Remove the heater inlet pipe from the coolant outlet housing.



Remove the heater by-pass at the coolant pump and the cylinder head.
Remove the radiator hose at the heater outlet housing.
Remove the heater outlet housing.
Remove both of the valve rocker covers. Refer to Valve Rocker Arm Cover Replacement .

Important
Retain the washers in the same orientation on the center bolts.






Remove the lower intake manifold bolts.
Remove the lower intake manifold.
Loosen the rocker arms.







Important
Keep the pushrods in order. The pushrods must be installed in the original position.


Remove the pushrods.



Remove the intake gasket.
Inspect the flatness of the inlet flanges.
Clean the following items:
Gasket material from the mating surfaces
Excess RTV sealant from the front and the rear ridges of the cylinder
Block
Sealing surfaces with degreaser
Installation Procedure

Important
All gasket-mating surfaces need to be free of oil, and foreign material. Use GM P/N 12346139 (Canadian P/N 10953463) or equivalent to clean surfaces.






Install the intake manifold gasket.



Install the pushrods.
Install the pushrods in their original location.
Coat the ends of the pushrods with prelube GM P/N 1052356, or the equivalent.
Intake pushrods are 144 mm (5.75 in).
Exhaust pushrods are 152.5 mm (6.0 in).
Ensure that the pushrods seat in the lifter.

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Install the rocker arm bolts. Tighten
Tighten the bolts to 10 N·m (89 lb in) +30 degrees.






Important
All gasket-mating surfaces need to be free of oil, and foreign material. Use GM P/N 12346139 (Canadian P/N 10953463) or equivalent to clean surfaces.


With gaskets in place apply a small drop 8-10 mm (0.31-0.39 in) of RTV sealer GM P/N 12346141 (Canadian P/N 10953433) or equivalent to the 4 corners of the intake manifold to block joint (1).
Connect the 2 small drops with a bead of RTV sealer that is between 8-10 mm (0.31-0.39 in) wide and 3.0-5.0 mm (0.12-0.20 in) thick (2).
Install the lower intake manifold.




Important
All lower intake manifold bolts need to be cleaned, free of any foreign material, and reused only if new bolts are unavailable. Use GM P/N 12345382 (Canadian P/N 10953489) or equivalent and apply to the old intake manifold bolt threads.



Important
Manufacturer recommends the center bolts be fully torqued before the diagonal bolts to assure proper seal ability.



Important
Lower intake manifold bolts in location 6 and 7 should be torqued to specification using a crows foot type tool.


Install the lower intake manifold bolts. Tighten
Tighten the lower intake manifold bolts in sequence to 7 N·m (62 lb in) on the first pass.
Tighten the lower intake manifold bolts (1, 2, 3, 4) in sequence to 13 N·m (115 lb in) on the final pass.
Tighten the lower intake manifold bolts (5, 6, 7, 8) in sequence to 25 N·m (18 lb ft) on the final pass.
Install the water outlet housing.
Install the radiator hose to the thermostat housing.



Install the heater inlet pipe to the thermostat housing.




Important
Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.


Install the fuel injector rail assembly.
Install the fuel injector O-rings using GM P/N 12345616, (Canadian P/N 993182) or equivalent.
Install the injector nozzles into the lower intake manifold injector bores.
Press on the injector rail using the palms of both hands until the injectors are fully seated.
Install the fuel injector rail bolts. Tighten
Tighten the fuel injector rail bolts to 10 N·m (89 lb in).





Install the fuel feed and return pipe retaining clip.
Install the fuel feed and return pipe retaining clip bolt. Tighten
Tighten the fuel feed and return pipe retaining clip bolt to 8 N·m (71 lb in).





Install the upper intake manifold. Refer to Intake Manifold Replacement .
Install the valve rocker covers. Refer to Valve Rocker Arm Cover Replacement .

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[Holeshot]

^^^^ The above info is from my GM SI Repair CD's Mike if want a print out let me know. Ill do it at work for you when you come in for parts.

[Car Guy]

How hard of a job is this? I have to get it done on a friends car. Anyone have any tips or tricks for this job?

Pretty straight forward, but if you spend the time to do it order the metal/rubber gaskets instead of the el-cheapo plastic/rubber ones that will leak again in no time [factory junk]. Also, for the 4-5 inch section to where the block/heads/intake all meet up use an aluminized RTV sealer and not the cheap sh*t from. I've screwed up when using that stuff and it still holds true, where as the cheap stuff has leaked even when everything was perfect.....






:3gears::3gears::3gears:

[88Nightmare]

dan, thats some good info right there. I'll try to make it there on my lunch break tomorrow, otherwise I'll be in Tuesday. I will call you tomorrow for sure though.

[Karps TA]

I love the fact that GM hasn't been able to fix that intake gasket problem in basically 20 years. 2.8, 3.1, 3400 same shit.

[Holeshot]

Its called stable repeat income LOL

[70challenger]

those things are gravy. calls for 6 hours. if the car does have the dog-bone style engine mounts, see if u can borrow a puller from somebody. it makes the job much easier. (the tool reqires u to remove both upper mounts that attatch to the radiator support and the tool slips in between and pulls the motor forward)

[Russ Jerome]

Good torque wrench, as mentioned do upper/lower.
Dump the orange lifetime coolant, go green (thats
why they leaked in the first place).

[Russ Jerome]

I love the fact that GM hasn't been able to fix that intake gasket problem in basically 20 years. 2.8, 3.1, 3400 same shit.

Poor middle managment decision to run the acidic orange crap
must have been big money. My first weekend with my 94 Impalla
SS was spent dumping and flushing the alloy eating crap from
my car. I have never seen a comeback using cheapo Felpro
gaskets and green coolant even working downtown where our
customer base was no maintanance owners (23rd/ Clybourn).
Even drunken backyard intake gaskets for freinds are still on
the road, again cheapest parts I could get and K-mart green
coolant.

[Car Guy]

Its called stable repeat income LOL

Which is why the foriegn car companies are taking over...!!! It's a free economy, why would you want to put out a product that is constantly going bad. People aren't dumb and eventually they'll try something else [and stick with it] that lasts more than 60k without needing 'un-nessecary' work.....

The way I look at it is you can 'rape' everybody once and they'll never come back or you can give them there $$$ worth and you have a customer for life. That's one of the big reasons I don't care for GM in general, same stupid easily fixable problems for almost a quarter century now. It's not the way to do business if you want to stick around in this world.....




Dump the orange lifetime coolant, go green (thats
why they leaked in the first place).

Oh yeah I forgot about that, but some people don't like to that because the factory 'calls' for the orange and if you put in the green stuff nothing will work right.....:rolleyes:






:3gears::3gears::3gears:

[Karps TA]

It's not just the orange coolant. My 93 Grand Prix never had dexcool in it. And It had the gaskets replaced at around 60K. My 02 Monte had to have them replaced last year at around 60K as well. Atleast GM came to the table with that one and paid the labor while I paid parts.

I don't know if I know anyone who hasn't had to have that done.

[Z28Envy]

Just had to get them replaced on our 98 Grand Am. My friend did it and he said it was a little harder on the 3.1 than the 3.4.

[Berettaspeed]

i love these things. ill do it for ya and have it back in say 3 hours? after 03 they upgraded to the metal gaskets. alot of short trips will cause this probelms as well. very easy to do, just remeber where the bolts go.

3100s and 3400s are basicly the same engine. even the 2.8/3.1 has this probelms, but not as bad. the 3800s have another intake probelm. buts its money in my pocket. ya for GM!

[88Nightmare]

im not gonna pay someone to do it when im fully capable of doing it myself, Just wondered if there were any tips or tricks to doing this job, or if there was a need for any specialty tools other then a torque wrench.