HEMI: Intake to Heads Oil Leak
#1420295
04/15/13 02:43 PM
04/15/13 02:43 PM
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Joined: Jan 2003
Posts: 9,670 Lima, Peru
domingo
OP
EL Master
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OP
EL Master
Joined: Jan 2003
Posts: 9,670
Lima, Peru
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Hi guys! This is the 3rd time Im having to remove my intake because it keeps sucking oil from the Valley area into the intake ports and then into the chambers, fouling the plugs with oil after a few minutes of running time.... I have checked proper alignment, bolt interference with the intake bolt holes, etc....face of intake is parallel with heads....so its not that the faces are crooked and not sealing right one against the other, they are nice and parallel whenI shim them and then I check them with a gauge on all 4 corners. I have glued the head side of the gasket to the head with silicone, and I have left the intake side of the gasket with NO silicone, just some grease....but its still sucking oil. Im sick of this so Im just gonna silicone both side of the gasket to assure a tight leakproof seal. Now, my other concern is the torque Im applying to the intake bolts. Richard Nedball's book asks for 25 ft-lbs torque on these bolts....but it sure looks like a lot to me. Its just 1/4" bolts threading into ALUMINUM cylinder heads. I have just tightened them with a small socket wrench till I felt they were were tight enough, didnt want to overtighten them and risk stripping threads on my brand new ALUMINUM heads!! Should I just go ahead and torque them at 25 lbs-ft??? Is it safe to do so on aluminum heads? Still it sound like a lot for such a small fastener threading into aluminum.
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Re: HEMI: Intake to Heads Oil Leak
[Re: hemi-challenger]
#1420297
04/15/13 04:15 PM
04/15/13 04:15 PM
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Joined: Jan 2012
Posts: 2,645 Stuttgart, Arkansas
rickseeman
master
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master
Joined: Jan 2012
Posts: 2,645
Stuttgart, Arkansas
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Ditto, re-read that. It's 72 in lbs on some and I think 48 in lbs on the others. Thats 4 ft lbs and 6 ft lbs!!! The proper intake torque and sequence is in the Mopar Hemi engine manual which should be on top of your work bench.
2011 Drag Pak Challenger
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Re: HEMI: Intake to Heads Oil Leak
[Re: domingo]
#1420299
04/15/13 06:03 PM
04/15/13 06:03 PM
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Joined: Jan 2012
Posts: 2,645 Stuttgart, Arkansas
rickseeman
master
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master
Joined: Jan 2012
Posts: 2,645
Stuttgart, Arkansas
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I love Rich and his book is the best but it is wrong on this. Use the torque values and sequence in the Mopar Hemi engine book. That is the only way to do it right. The bolts will loosen up after you run it several times. Retorque every month until it settles in. If possible I prefer to use studs on aluminum heads. I get mine from ARP.
2011 Drag Pak Challenger
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Re: HEMI: Intake to Heads Oil Leak
[Re: rickseeman]
#1420300
04/15/13 07:05 PM
04/15/13 07:05 PM
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Joined: Jan 2003
Posts: 7,489 Minnesota
Hemi_Joel
master
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master
Joined: Jan 2003
Posts: 7,489
Minnesota
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I read somewhere that because the bolts are verticle, if you over-tork the intake bolts, it can wedge the heads apart and crack the block!
[img]http://i.imgur.com/boeexFms.jpg[/img]31 Plymouth Coupe, 392 Hemi, T56 magnum RS23J71 RS27J77 RP23J71 RO23J71 WM21J8A I don't regret the things I've done. I only regret the things I didn't do. "Wise men talk because they have something to say; fools because they have to say something. ~ Plato"
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Re: HEMI: Intake to Heads Oil Leak
[Re: Mopar_Rich]
#1420305
04/15/13 11:41 PM
04/15/13 11:41 PM
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Joined: Jan 2012
Posts: 2,645 Stuttgart, Arkansas
rickseeman
master
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master
Joined: Jan 2012
Posts: 2,645
Stuttgart, Arkansas
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Another thing to check is intake fit. Let's say the block was decked alot. Now the holes in the intake don't line up with the threads in the heads. The intake bolts end up hitting the sides of the intake. You can be tightening the intake and it feels snug but you are really just jamming the bolts. To check this, put intake manifold studs in the heads, (best without the intake gaskets on), and see if the intake manifold will slide all the way down to the head. If not you will have to get a rat tail file and elongate the holes in the intake manifold until it will slide down to the head without wedgeing into the studs.
2011 Drag Pak Challenger
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Re: HEMI: Intake to Heads Oil Leak
[Re: domingo]
#1420306
04/16/13 12:04 AM
04/16/13 12:04 AM
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Joined: Aug 2003
Posts: 43,163 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,163
Bend,OR USA
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Be very careful on which type silicone you use on intake gaskets, I like and use "adhesive" silicone only on any gasket that is exposed to oil Make sure the label says Adhesive silicone, not gasket maker or any other label Let it dry 24 hrs or more
Last edited by Cab_Burge; 04/16/13 12:06 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: HEMI: Intake to Heads Oil Leak
[Re: rickseeman]
#1420309
04/16/13 11:31 AM
04/16/13 11:31 AM
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Joined: Jan 2003
Posts: 9,670 Lima, Peru
domingo
OP
EL Master
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OP
EL Master
Joined: Jan 2003
Posts: 9,670
Lima, Peru
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Quote:
Another thing to check is intake fit. Let's say the block was decked alot. Now the holes in the intake don't line up with the threads in the heads. The intake bolts end up hitting the sides of the intake. You can be tightening the intake and it feels snug but you are really just jamming the bolts. To check this, put intake manifold studs in the heads, (best without the intake gaskets on), and see if the intake manifold will slide all the way down to the head. If not you will have to get a rat tail file and elongate the holes in the intake manifold until it will slide down to the head without wedgeing into the studs.
I caught this the first time around and elongated the manifold holes....still after doing this im still sucking oil into the intake ports.....
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Re: HEMI: Intake to Heads Oil Leak
[Re: domingo]
#1420310
04/16/13 11:36 AM
04/16/13 11:36 AM
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Joined: Jan 2003
Posts: 9,670 Lima, Peru
domingo
OP
EL Master
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OP
EL Master
Joined: Jan 2003
Posts: 9,670
Lima, Peru
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I glued it back on with grey silicone on both sides. Torqued the 4 center bolts more than the 4 outers....
we will see if the problem is solved this time around....
I used a set of MR Gasket 0,060 gaskets....even though they are thicker than what Id like to use for better port alignment(0,030 would be better) I am gonna try this time with the thicker ones to see if they seal better.
Port aignment is not exactly on center, its like the intake would like a thinner gasket to go down a bit more so the intake ports are more on center with the head ports....
although the intake is sitting a bit high and the ports are not perfectly concentric, I am still not seeing a "step" whhen looking down from the carb opening into the intake ports. The top oprtion of the intake runner is perfectly flush with the port roof on the heads, and the lower portion of the intake runner sits about 1/8" higher than the intake port...(the stage V intake ports are smaller than the head ports...the heads are CNCd and gasket matched,k the stage V intake is untouched, hence the smaller runner openings).
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Re: HEMI: Intake to Heads Oil Leak
[Re: hemi-itis]
#1420311
04/16/13 11:54 AM
04/16/13 11:54 AM
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Joined: Mar 2006
Posts: 9,910 Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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If leaking at the bottom persist carefully check the following areas: Head to manifold alignment(top to bottom) Head to manifold angle and gasket thickness that's required. Manifold to block rail spacing(make sure nothing is holding the manifold up) Head intake surface flat and not cut at an incorrect angle front to back,Check same for the intake surface. Make sure there is no warped surfaces. The angle and straightness can be checked buy using four block(steel) guages at all four corners then check all the areas at each port for discrepencies and if the four corners don't set tight on the corner guages then you know something is out of square. We usually use 2"X 1"X .060 thick block steel guages at all four corners and check for the manifold setting flush on the guages and then pass a aluminium welding rod flattened to just a hair under .060 through the port area to see if it's loose or tight in any one spot. We never use any torque values when tightening the intakes but use a sequence of side to side and repeat till there is no more bolt rotation with a 1/4 drive then we repeat it after the engine has heat cycled a few times.We also recheck them every few seasons if the engine sets for long period of time.
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Re: HEMI: Intake to Heads Oil Leak
[Re: domingo]
#1420312
04/16/13 12:01 PM
04/16/13 12:01 PM
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Joined: Apr 2005
Posts: 1,505 TN
SCATPACK 1
pro stock
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pro stock
Joined: Apr 2005
Posts: 1,505
TN
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Dom what are you using to seal the ends of the intake to the block? Are you just using silicone or are you using the gasket that is supplied with the intake gaskets for the end rail. I had a problem with those gaskets holding the intake up too high and the intake gaskets would not seal properly. I left out those end gaskets on each end and just used silicone on the ends and then the intake gaskets sealed up on the ports with no leaks. Just a thought
Old Geezer Racing
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