INTAKE GASKET MAIN PAGE, PLEASE POST Q'S&A'S HERE!

[LexVenture]

Hello, I like to thank everybody who posted all the helpful information on doing this intake gasket replacement job! I am now half way through with the front old intake manifold gasket out.

I do have some questions:
1. I know I should have a shop manual but haven't found it locally yet. Meanwhile, can somebody tell me the torque spec for rocket arm retaining bolts? I broke them loose at around 40 ft-lb.
2. While I'm seeing the cylinder head bolts, should I check the torque? What should they be?
3. When I detach the short metal pipe out from the thermostat housing, I broke a hard plastic piece at the tip of the pipe (between the metal fitting and the rubber 0-ring). Just wonder whether I can just get a replacement piece from the dealer or the local parts store.

Thanks,
Bob

Edit / follow up:
Great forum! I did some search and have found some answers:
1. Rocker arm bolts torque: First torque to 168 in-lb then torque an additional 30 degrees.
2. Head bolts torque: Torque to 37 ft-lb and then an additional 90 degrees. Head bolts are stretch bolts so I believe they should not be loosen and then re-torqued.

[iceman2]

My efforts ended in failure, I am replacing the entire engine on my 1997. After several weekends and several hundred dollars I thought I'd done a great job, I failed to ensure all of the sludge was cleaned out of the oil system and the engine died from metal to metal contact as oil was not apparently flowing to the crankcase, believe the screen was clogged. Lesson learned - flush your oil system (hot) several times right after you change the head and/or intake gaskets, best indicator of this problem will be your mpg - on the 3.4L, you should be over 20, I was right around 15, I knew something was wrong but couldn't figure it out. Also, if you have any kind of metal to metal contact, your engine will warm up very quickly.

[OOge]

Could someone be so kind to tell me the most import things that i need while changing the intake.
e.g is the fuel pump o-ring [FONT='Calibri','sans-serif']Necessary [/font]to order.
Here in Europe the parts are way to expensive, so i want to order everything i [FONT='Calibri','sans-serif']Necessary[/font] need in the US. It will be a waste if something appears to be needed, and not ordered.

thanks

[Sparky1349]

Originally Posted by OOge

Could someone be so kind to tell me the most import things that i need while changing the intake.
e.g is the fuel pump o-ring [FONT='Calibri','sans-serif']Necessary [/font]to order.
Here in Europe the parts are way to expensive, so i want to order everything i [FONT='Calibri','sans-serif']Necessary[/font] need in the US. It will be a waste if something appears to be needed, and not ordered.

thanks

Hey OOge, The absolute minimum you need to do the job is the upper and lower gasket set, front coolant bypass tube to water pump o-ring (this comes with the lower gasket if you buy the Felpro gasket), valve cover gasket set and the EGR valve gasket. That being said I would also get the lower fuel injector o-ring set because when you pull the injectors out to get at the lower intake bolts you're pulling the o-rings over all that old aluminum corrosion, it's cheap insurance (Note: don't pull the injectors out of the fuel rail or disconnect the rail from the fuel hoses, just disconnect it from the lower intake and flip it over on top of the drivers side fender that way you won't have to replace those o-rings). You will also want to replace the o-ring for the heater pipe that goes into the thermistat housing, I could find this o-ring only at the Chevy dealership, none of the autoparts stores had it. In addition your going to want to replace the coolant and to do an oil change after you put it all back together.

The standard recommendations at this point is to replace the spark plugs, spark plug wires, thermostat (and thermostat gasket), and the distributer plug o-ring (the aluminum plug under the thermistat where the distributor use to be plugged in before electronic distributorless ignition). Since you have to order parts from here you should assess that condition the air filter, serpentine belt, coolant bypass hose and the radiator hoses since all of those parts will have to come out to replace the IMG anyway.

Oh, one more thing....If you don't have a 10mm crowfoot wrench and inch pound torque wrench plan on picking those up too since you can't do the job with out them.

Good luck, hope this helps.

Sparky

[OOge]

Originally Posted by Sparky1349

Hey OOge, The absolute minimum you need to do the job is the upper and lower gasket set, front coolant bypass tube to water pump o-ring (this comes with the lower gasket if you buy the Felpro gasket), valve cover gasket set and the EGR valve gasket. That being said I would also get the lower fuel injector o-ring set because when you pull the injectors out to get at the lower intake bolts you're pulling the o-rings over all that old aluminum corrosion, it's cheap insurance (Note: don't pull the injectors out of the fuel rail or disconnect the rail from the fuel hoses, just disconnect it from the lower intake and flip it over on top of the drivers side fender that way you won't have to replace those o-rings). You will also want to replace the o-ring for the heater pipe that goes into the thermistat housing, I could find this o-ring only at the Chevy dealership, none of the autoparts stores had it. In addition your going to want to replace the coolant and to do an oil change after you put it all back together.

The standard recommendations at this point is to replace the spark plugs, spark plug wires, thermostat (and thermostat gasket), and the distributer plug o-ring (the aluminum plug under the thermistat where the distributor use to be plugged in before electronic distributorless ignition). Since you have to order parts from here you should assess that condition the air filter, serpentine belt, coolant bypass hose and the radiator hoses since all of those parts will have to come out to replace the IMG anyway.

Oh, one more thing....If you don't have a 10mm crowfoot wrench and inch pound torque wrench plan on picking those up too since you can't do the job with out them.

Good luck, hope this helps.

Sparky

Thanks, but assuming that a OEM GM intake manifold is a beter product, can you tell me the partnumber of the front coolant bypass tube to water pump o-ring. I can't find it.

[Sparky1349]

Originally Posted by OOge

Thanks, but assuming that a OEM GM intake manifold is a beter product, can you tell me the partnumber of the front coolant bypass tube to water pump o-ring. I can't find it.

Hey OOge,

I tried some of my favorite place to look for parts (like gmpartsdirect.com and rockauto.com) and I couldn't find it either. Here is a picture of the cooling components:




The O-ring is on the bypass pipe (number 18), right below the bleeder screw which is number 19. Maybe you can take this picture to a parts place and find out the part number of the o-ring.

Hope this helps.

Sparky

[OOge]

Originally Posted by Sparky1349

Hey OOge,

I tried some of my favorite place to look for parts (like gmpartsdirect.com and rockauto.com) and I couldn't find it either. Here is a picture of the cooling......

Sparky

Thanks for all the help.
I've made a list at gm-auto-parts.com (they ship worldwide with USPS) and find the following things.

Part Number: 89017279 Fuel system - Fuel induction - Intake - Manifold gasket Manifold gasket, 3.4l 1997 - 2003
Part Number: 24506439 Emission system - Egr system - Valve gasket Valve gasket, 3.4l 1996
Part Number: 10241048 Emission system - Emission components - Egr tube - Gasket 3.1 liter 1996
Part Number: 10189205 Cooling - Radiator and components - Pipe - Seal Seal - 3.1 liter 1995 - 1999
Part Number: 10154775 Engine - Cylinder head & valves - Valve cover gasket Valve cover gasket, all models - 3.4l 1997 - 2005
Part Number: 17113544 Fuel system - Fuel induction - Fuel injection - Seal kit Seal kit, mpfi w/turbo, syclone, typhoon 1992 - 1993
Part Number: 17113034 SEAL KIT
Part Number: 11609991 BOLT Part number 11588914 was superceded by part number 11609991.
Part Number: 11588915 BOLT

Did i forgot something. With exception of the filters.

[SEMORiverHills]

Hello everyone, AF newbie here. I have a 98 Venture, with 192,000 miles. It's gasket time (at least I hope that's the extent of my van's issues). I have read every page of this thread, and the amount of detailed information based on real experience by 'the average home mechanic' has inspired me to take on the seemingly beastly task of replacing my IMG and head gaskets.
A quick background summary:
- I am the 2nd owner of this van (my MIL/FIL bought it new). I purchased it about 11 months ago, and have driven it approximately 11,000 miles. It has never had the IMG or head gaskets replaced. For that matter, this Venture's still running on factory plugs and plug wires (my in-laws never had it tuned up because "it always ran good.")
- Big problems started a few weeks ago, when my wife informed me she got a CEL, and the van 'ran rough' while she was in town one day. She said no gauges or dummy lights indicated any trouble, only the CEL and idle that was noticeably rougher than usual.
- That evening, I was going to take the van to Autozone to have the DTC pulled. Cold start, then 2 miles down the highway, then redline on the temp gauge and dummy light on for overheat. Stopped the van immediately, checked the upper radiator hose - still cold, not pressurized, and cooling fans not running. No coolant had entered the overflow reservoir, and the radiator cap was cool to the touch.
- Drove the van 2 more miles to my Dad's shop, parked, checked under the hood while idling. Upper radiator hose had heated up and pressurized, cooling fan was running, radiator cap hot. Temp gauge fluctuating from normal reading to top end of normal range. This was the first time that ever happened with this vehicle...temperature had always topped out about a third of the way into the normal range then stayed there.
- Since then, I have replaced:
Coolant Temperature Sensor, Thermostat, Water Pump, Flushed Coolant System and filled with new Dexcool. After all of that, temperature gauge actually read worse - would go to near the red, and park there.
- Made appt with reputable local dealer for diagnosis, as the gauge checked out OK per the check Haynes manual prescribes.
- Started van to drive to dealer, and ran very rough, and a tremendous amount of white smoke billowing from the exhaust. Flashing CEL. Idled very rough, and significant hesitation at takeoff.
- Drove approx 5 miles (highway), in the next town, it died at a stoplight. Restarted only with a lot of pedal while cranking, then wouldn't get over 20 mph. Pulled over immediately, had it towed the rest of the way to the dealer.
- Dealer pulled valve cover, and definite coolant mixed with oil (the infamous milkshake / jelly situation.
- Dealer determined much coolant entering #6 cylinder.
- Dealer took intake manifold loose to inspect gasket, said IMG actually in pretty good shape. Told me they're certain bad HG or cracked head.
- Now I have it back, ready to take this puppy on and avoid the approx $1,000 estimate to replace both head gaskets and IMG.

Sorry for the long post, I just wanted to provide plenty of detail on what's happening with this van, as this is my 'introductory post' so to speak.

So, procedure-wise, I'm sure I'll be back with questions here and there, but everything appears to be pretty straightforward so far. I just have 2 questions off the top:

1. Does anyone have or know of any pictures of the engine rotated forward (preferably a pic that included the rad support / cooling fan area, to provide me with some guideline on how far to rotate). I would also be interested in seeing some pics of how the rotation was done and the engine secured, as the most detailed posts I have read on this operation refer to using an engine hoist to tie off to, which I do not have at my disposal right now.

2. Once the rear head is loose and ready to remove, how is the clearance? What can I expect there?

I'm nervous as can be about this, as the guys at the dealer service shop told the wrecker driver to tell whoever was doing the work 'good luck.'

Thanks in advance for any input or guidance you can provide.


Andy

[SEMORiverHills]

Is anyone with experience R&R heads on these vans still monitoring this thread? I apologize for coming across as a little antsy; I'm just targeting getting the heads off of this 3400 this weekend, and it would be great to know that there are folks with knowledge I can draw on as I dive into this project.

Thank you so much for any knowledge and insight you can provide. Have a good one!

Andy

[kornjulio]

Originally Posted by SEMORiverHills

1. Does anyone have or know of any pictures of the engine rotated forward (preferably a pic that included the rad support / cooling fan area, to provide me with some guideline on how far to rotate). I would also be interested in seeing some pics of how the rotation was done and the engine secured, as the most detailed posts I have read on this operation refer to using an engine hoist to tie off to, which I do not have at my disposal right now.

Andy

I did the LIMG on mine this past summer. I used a wratchet tie-down to rotate the engine. Hook it from the bracket on the engine, across the front bumper, then loop it to the crossmember on the engine cradle underneath. Rotate it as much as you need - it'll go pretty far.

[534BC]

Well, I'm about to join the club. After getting a pressure test and estimate , my guy can't get to it right away so I'll do i tmyself. Hopefuly is just the gaskets.

A Chevy dealer did this job in 2002 with 34,000 miles and now it has 100,000 and I keep adding a quart of water every month.

I'll do plugs, wires, gaskets and whatever else needs done. I read nearly every page of this thread, very helpful. Thanks.

[534BC]

I pulled my engine forward by hand and used multiple bugee cords to tie it forward. It's pretty easy, I wish I'd done it a lot earlier.

Here's the latest GM gaskets for intakes with upper, lower, and bolts.

19169127 kit was cheaper than aftermarket (and includes bolts)

The question is do I use the sealing washers for the 4 long bolts that seal vacuum?

The new bolts in addition to haveing loctite also have a white sealing substance under the boltheads.

I'm inclined to think not to use the washers , what you all think?

['97ventureowner]

Originally Posted by 534BC

Here's the latest GM gaskets for intakes with upper, lower, and bolts.
19169127 kit was cheaper than aftermarket (and includes bolts)

Excellent information! I wasn't aware that this was available. I like the idea of the "kit" as it also contains the bolts. Many people elect to not get the new bolts per GM's TSB recommendation. Now it's all included in one handy package.

[Sparky1349]

Originally Posted by 534BC

I pulled my engine forward by hand and used multiple bugee cords to tie it forward. It's pretty easy, I wish I'd done it a lot earlier.

Here's the latest GM gaskets for intakes with upper, lower, and bolts.

19169127 kit was cheaper than aftermarket (and includes bolts)

The question is do I use the sealing washers for the 4 long bolts that seal vacuum?

The new bolts in addition to haveing loctite also have a white sealing substance under the boltheads.

I'm inclined to think not to use the washers , what you all think?

Hey, The 4 center bolts don't actually seal manifold vacuum they kind of go through free space under the manifold into the lifter valley. I would install the gaskets since it acts as a seal for the negative pressure inside the engine from the PCV valve. I seem to recall that the original equipment center bolts had some kind of seal under the bolt head also.

Good luck,
Sparky

[534BC]

The four bolts have a sealant, I decided to not use the old seals. The bolts "pass thru" manifold vaccum so if the bolt heads leak then it sucks air. After they wer tightend it was very evidant that the sealer is put on there for a reason. Looks good, I'm almost done with mine and do recommend the GM intake kit.

After doing this whole job, I kick myself in the butt and highly recommend one to simply tighten at least the outer 4 bolts (in my case it would've fixed the problem) I should've guessed it when I heard that the "bolts come loose" anyways, mine wasn't too late to catch it in time.

Two things also come to mind after seeing things:
The machine job on the intake is terrible with a terrible steps, finish, and hopefully the angle is correct. If I had to do it again I'd get a very light pass done on a grinder as the smooth surface would probably be far more forgiving with metals sliding up against the gasket. The head surface and uper intake wasn't nearly as bad a milling job.

The second thing is the design with in effect 1 bolt per 5 ports is bound to give more trouble than a design with 2 effective bolts per port. The 4 middle bolts help somewhat and probably do more to control flex than anything else. I'm surpised it does as good as it did.

An engineering marvel that went slightly off kilter, lol.