Intake Manifold 540, HELP!
09-21-2006, 06:54 AM
#1
Intake Manifold 540, HELP!
I have a Dart Big M block, 9.0:1 static compression, 4.500" bore x 4.25" stroke, 9.800" deck, Crane 741 hydraulic roller cam, Crane roller lifters, AFR 315 CNC heads with backcut Del West stainless intake valve, Del West inconel exhaust valves, Isky (PSI) "Tool Room" springs, Crower stainless rockers, JE forged pistons, Crower 4340 billet 6.386 rods, Crower semi-lightweight 4340NT crank, Victor Jr intake, Holley marine 850cfm 4150 carbs, MSD Pro-Billet Distributor.
The problem is in the corner where the heads meet the intake on both motors above the timming chain. I have done the intake gasket twice on each side. I am using Mr. Gasket gasket set, Black RTV Silicon ( I am allowing it to film up for about 20min before applying) , I follow the order for intake bolting and I am applying 30lbs with a torque Wrench.
It is just a tiny drip, but it pisses me off becasue my bilge is red, motor is red and everything else is clean. I can't seem to stop this. I am willing to do it one more time. Any input would be great. The gaskets come with the cork front and backs but I have been using the silicoln becasue everyone says not to use them because they are junk
The problem is in the corner where the heads meet the intake on both motors above the timming chain. I have done the intake gasket twice on each side. I am using Mr. Gasket gasket set, Black RTV Silicon ( I am allowing it to film up for about 20min before applying) , I follow the order for intake bolting and I am applying 30lbs with a torque Wrench.
It is just a tiny drip, but it pisses me off becasue my bilge is red, motor is red and everything else is clean. I can't seem to stop this. I am willing to do it one more time. Any input would be great. The gaskets come with the cork front and backs but I have been using the silicoln becasue everyone says not to use them because they are junk
09-21-2006, 07:57 AM
#2
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Re: Intake Manifold 540, HELP!
I always use silicone at the front and back of the intake. A thick bead, 1/4 dia. or so. Make sure it ovelaps the intake gaskets. I always put the intake on while the silicone is still wet. No leaks there ever.
09-21-2006, 08:55 AM
#3
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Re: Intake Manifold 540, HELP!
I agree with PatriYatch. I always put just a little extra on the ends where the RTV meets the intake gaskets.
From my experience, if you're waiting until the RTV "skins" over, that's the problem. I've done it that way a couple of times and it leaked. I know thats what a lot of people say you should do, but if the RTV starts to dry, it won't adhere to the manifold, which is the reason you're using the Black (Adhesive) RTV in the first place.
What you don't want to do is to have to move the manifold around alot to line up the intake bolt-holes as this will squish out the wet RTV. Try to line it up perfect as you're lowering it down. A steady set of other hands helps a bunch too.
Hope this helps.
From my experience, if you're waiting until the RTV "skins" over, that's the problem. I've done it that way a couple of times and it leaked. I know thats what a lot of people say you should do, but if the RTV starts to dry, it won't adhere to the manifold, which is the reason you're using the Black (Adhesive) RTV in the first place.
What you don't want to do is to have to move the manifold around alot to line up the intake bolt-holes as this will squish out the wet RTV. Try to line it up perfect as you're lowering it down. A steady set of other hands helps a bunch too.
Hope this helps.
09-21-2006, 08:59 AM
#4
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Re: Intake Manifold 540, HELP!
What they said + :
A good tech tip that may help:
When you intall intake, snug bolts up to ony about 10-15ft/lbs and let sit for a good amt of time, then go back and do your sequence up to recommended torque.
This lets silicone dry only partially compressed. Then you torque down intake to final specs which then puts more pressure on the silicone.
A good tech tip that may help:
When you intall intake, snug bolts up to ony about 10-15ft/lbs and let sit for a good amt of time, then go back and do your sequence up to recommended torque.
This lets silicone dry only partially compressed. Then you torque down intake to final specs which then puts more pressure on the silicone.
09-21-2006, 09:30 AM
#6
Registered
Re: Intake Manifold 540, HELP!
Another tip, clean all gasket surfaces to the metal and then use laquer thinner on them to remove all oil. Silicone doesn't adhere to oily surfaces.
09-21-2006, 12:28 PM
#7
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Re: Intake Manifold 540, HELP!
And use the RTV called great stuff or good stuff made by permatex. It is almost like a rubber epoxy when it dries,hard to clean off but you can almost use it on a rear end cover or oil pan on a car and take the bolts off after it is completely dry and it still won't leak,Smitty
09-21-2006, 01:02 PM
#10
Banned
Re: Intake Manifold 540, HELP!
Originally Posted by articfriends
And use the RTV called great stuff or good stuff made by permatex. It is almost like a rubber epoxy when it dries,hard to clean off but you can almost use it on a rear end cover or oil pan on a car and take the bolts off after it is completely dry and it still won't leak,Smitty
