Torque on the manifold Bolts
Via LS1HowTo.com
Once all 10 intake manifold bolts are hand threaded as far as they'll go, tighten them down with a wrench and then torque in the order shown in the picture on the left. You need to torque these down in a 2-pass fashion..the first pass, tighten to 44 INCH-lbs, then, on the 2nd pass torque them to 89 INCH-lbs. Again, note those specs are in INCH lbs. If you don't have an inch pounds torque wrench, just tigthen the bolts hand tight...its only about 7 ftlbs of torque on that final pass and the intake seals with rubber gaskets so its doesn't need much pressure at all to seal.
**I'm guessing this is where you say you meant the exhaust manifold bolts...**
If so, those bolts are 18ft lbs
Once all 10 intake manifold bolts are hand threaded as far as they'll go, tighten them down with a wrench and then torque in the order shown in the picture on the left. You need to torque these down in a 2-pass fashion..the first pass, tighten to 44 INCH-lbs, then, on the 2nd pass torque them to 89 INCH-lbs. Again, note those specs are in INCH lbs. If you don't have an inch pounds torque wrench, just tigthen the bolts hand tight...its only about 7 ftlbs of torque on that final pass and the intake seals with rubber gaskets so its doesn't need much pressure at all to seal.
**I'm guessing this is where you say you meant the exhaust manifold bolts...**
If so, those bolts are 18ft lbs
Y'all's mean. 9 posts man. Search on this site is not the best.
Welcome OP, good answers available here, including from the gents above. FWIW ls1howto has a lot of good info, but double check everything you can by searching this site. Google works better than the site search.
Welcome OP, good answers available here, including from the gents above. FWIW ls1howto has a lot of good info, but double check everything you can by searching this site. Google works better than the site search.
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Repeated leaking on intake manifold Hey guys, so I followed this spec here and verified it with others. now this is the second time redoing this intake in the last 3 months. its fine for a cpl months the first time, this time a cpl hours. I tried tightening it down more, maybe Im crazy but it seems as it made it worse... has anyone else had this issue? I'm trying to decide now if i should RTV this thing down any advise against that? I ain't doing this a fourth time, so this time it has to work lol.
09 escalade LSA GEN 4 6.0 2 mode hybrid
09 escalade LSA GEN 4 6.0 2 mode hybrid
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TECH Addict
Joined: Dec 2017
Posts: 2,180
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If you look closely at The System, what it does is, the bolts tighten down SOLID against that metal sleeve, and then there's just abuncha rubber that actually grabs the intake. Any torque greater than around 7 ft-lbs (84 in-lbs) up to the point of stripping the threads, isn't gonna make a damn bit of difference to the intake sealing.
The torque "spec" is really more of a FACTORY thing, than a "must follow" out here in The Real World. In the factory, they have automatic (or nearly so) assembly tools, and they have to have SOME setting or other. But out here, all we need to do is, make sure they're TIGHT ENOUGH to properly compress the rubber and seat thoroughly against the sleeves, but not TOO TIGHT such that we strip the threads. Obviously the factory spec gets us there. Butt, understanding what we're REALLY DOING, as opposed to merely worshipping The Book, helps illuminate reality, and dissipate the hunger for Revelation.
I'd suggest starting over with new intake gaskets and new those rubber bushings.
I'd suspect something went sideways at your initial assembly, and it's too far gone to recover. It needs new at this point. The System is really quite reliable if something didn't slip out of place or whatever. That's why they designed it that way.
DO NOT use RTV. It dissolves in gasoline. Just use the parts in the kit, ALL OF THEM, with a little white lithium grease on everything including the bolt threads.
Incidentally, the "89" number is just, 35 metric units, converted to Imperial. Kinda like the 22 you see for rocker bolts: that's just, 30 N-m, out to 2 decimal places. These motors are metric at the factory.
The torque "spec" is really more of a FACTORY thing, than a "must follow" out here in The Real World. In the factory, they have automatic (or nearly so) assembly tools, and they have to have SOME setting or other. But out here, all we need to do is, make sure they're TIGHT ENOUGH to properly compress the rubber and seat thoroughly against the sleeves, but not TOO TIGHT such that we strip the threads. Obviously the factory spec gets us there. Butt, understanding what we're REALLY DOING, as opposed to merely worshipping The Book, helps illuminate reality, and dissipate the hunger for Revelation.
I'd suggest starting over with new intake gaskets and new those rubber bushings.
I'd suspect something went sideways at your initial assembly, and it's too far gone to recover. It needs new at this point. The System is really quite reliable if something didn't slip out of place or whatever. That's why they designed it that way.DO NOT use RTV. It dissolves in gasoline. Just use the parts in the kit, ALL OF THEM, with a little white lithium grease on everything including the bolt threads.
Incidentally, the "89" number is just, 35 metric units, converted to Imperial. Kinda like the 22 you see for rocker bolts: that's just, 30 N-m, out to 2 decimal places. These motors are metric at the factory.
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Make sure you use new gaskets.
Make sure the bottom of the intake isn't hitting anything, steam tubes, etc.
Spray the cylinder heads with WD40
Use blue loctite on the intake bolts
Do the first pass at 45 inch lbs
Second pass at 89inch lbs
Use a quality torque wrench.
Make sure the bottom of the intake isn't hitting anything, steam tubes, etc.
Spray the cylinder heads with WD40
Use blue loctite on the intake bolts
Do the first pass at 45 inch lbs
Second pass at 89inch lbs
Use a quality torque wrench.
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Overtightening the bolts WILL NOT have any effect whatsoever on the manifold itself. All that will happen is, the metal sleeve that the bolt tightens against, will be held more securely, up to the point that the threads strip
Overtightening the bolts WILL NOT damage the intake. Only (potentially) the heads.
Overtightening the bolts WILL NOT damage the intake. Only (potentially) the heads.
yes....blue lock tite is a must....those bolts seem to wanna get loose over time...and the intake bolt holes do go down into the engine so the lock tite does act as a sealant...without sealant potential vacuum leak.....i myself use Vaseline on the heads so the gaskets can slide around until they find their place as you TQ it down
and dont re use the gaskets.....get new
and dont re use the gaskets.....get new
IIRC, factory intakes only have the metal sleeves on the corners that help locate it on the head. Its been a long time since I've used or seen a factory intake. I don't think my FAST 102 uses them at all but its been a while since I put it on.
I've started using orange loctite instead of blue. The orange stuff is badass and is perfect for something like this.
I've started using orange loctite instead of blue. The orange stuff is badass and is perfect for something like this.
