LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Intake manifold leak causes

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Old 05-12-2007, 02:58 AM
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Default Intake manifold leak causes

Thanks to everyone that responded on my other intake manifold thread, this one I'm wondering what the cause is. It says in one of the write ups (http://www.geocities.com/MotorCity/Downs/4013/ol.html) that:

"The EGR pipe...yep, that's right...there are two types, the solid and the flex. The flex is the more common...of course, I have the solid. The pipe does a 180 degree bend right down the back left side of the intake manifold heading for its final hook up. On long trips, the temp inside that pipe can reach upwards to 700 degrees Farenheit! Now folks, that's darn hot! The intake is torqued down with 35 ft. pounds a bolt...that's not much. The sealant is weak, we knew that. The liquid sealant is used in the front and rear instead of cork because of the "wavy-dippy" surface on the manifold. Bottom line: pipe gets hot, left rear corner of mainfold lifts ever so slightly, pressure under manifold is looking for a way out...finds its weakest link and carves a passageway...drip drip drip, right down the left rear of the block. The hotter the motor, the bigger the drip...the longer you wait for repair, the bigger the drip. "

my question is: is it true?
Old 05-12-2007, 03:19 AM
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Yes. Check out the Edelbrock intake comparison. The alu lips where they press down on the block, are really thin and they warp from all that heat.
Old 05-12-2007, 04:09 AM
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Yea, that EGR Pipe gets a little warm back there and messes up the Seals.
Old 05-12-2007, 05:55 AM
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It is a combination of a poor design of the EGR pipe style and location, combined with a really cruddy seal, which is not a gasket but RTV sealant. Known issue, we all have to fix it. Did mine 2 years ago.
Old 05-12-2007, 01:53 PM
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so just lots of heat tape to fix that stupid egr plug?
Old 05-12-2007, 01:57 PM
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Originally Posted by Ironxcross
so just lots of heat tape to fix that stupid egr plug?

haha REMOVAL of it, to fix that problem. Get, or make, an EGR block off plate and then get the EGR tuned out. If you have to pass emissions, well I can't tell you if that'll effect it any.




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