Intake Manifold Sealer

[34ford]

What do you guys use for the ends on an intake manifold for sealer. I used the black gasket sealer and now have a leak on the front with only 3500 miles on the engine. It is a zz4 crate motor with the aluminum intake. I roughed up the surface on the block before I installed it. I do have a pvc valve on the passenger side and a breather on the driver side. I hate leakers.

Thanks

[wayne petty]

i personally use several sealers on intake manifold gaskets..


either 3m or permatex black super weather strip adhesive..
off brands of super weather strip adhesive are worthless..

ulltra grey silicone.. permatex 82194

sometimes some hylomar.. permatex 85420

clean the ends of the block with brake cleaner.. examine the end gaskets to see if the end seals sit in first or the intake gaskets sit in and the end seals over them...

i like gluing the side gaskets to the coolant openings on the heads so the gaskets will stay in place while i am installing and torquing the manifold   a loop of black superweather strip around the coolant openings in the head and the gaskets wiggled into it.. then separated for a minute then set back in and moved around until the  are kinda tight.. then the other side..

the end rails.. if the side gaskets go on top of them i run a bead of black super weather strip along the top of the block.. wiggle the end seals into it..  separate them for a minute or minute and a half..  then i set them into place .. work them in tight and do the other end.. 15 minutes but not longer than 30 minutes before i am ready to install the intake.. so its solid but will still mash down ever so slightly..

a dab of silicone sealer at the 4 corners where the end of the side gaskets meet the end rails..  i usually smear silicone sealer around the water opening in the side gaskets..  

hylomar around the cross over. this is usually done on both sides of the exhaust cross over area..  as the hylomar will seal the high temp area as its good for 500F..

the big X pattern  to torque the intake down.. going around the pattern several times after i have have reached final torque..

warning.. some vortec manifolds are only a few foot pounds..

there are many ways to perform this.. this is just the way i do it...

and if the manifold sits too tight on the end rails..  cleaning the end rails with brake cleaner..  running a nice bead of usually clear silicone RTV.66B. not silicone for glass as that can flow..  but you need to wait a while after installing the intake so the crankcase pressure or vacuum does not displace it..  probably an hour or two.

[Harry]

I have heard of using a centre punch and putting several small dimples in both surfaces to help hold the sealers in place.

[34ford]

Thanks Wayne.

I did do the dimples in the block before the install last time. Looked closer this weekend and it is leaking on the corners where the block, heat and manifold come together. Must not have put enough sealant on it. I used the black permatex black RTV sealer.  Is the ultra grey silicone like the factory sealer?  Not looking forward to this but need to get in the mood to do it.

[enjenjo]

I use Pematex Ultra blue. It has a quality that allows it to seal minor leaks.

[purplepickup]

Permatex product, "The Right Stuff".  Hooley uses it on his engines and from what I've seen it's the best RTV type sealer around.  I haven't put an engine together lately but when I do I'll use it.

[wayne petty]

Thanks Wayne.

I did do the dimples in the block before the install last time. Looked closer this weekend and it is leaking on the corners where the block, heat and manifold come together. Must not have put enough sealant on it. I used the black permatex black RTV sealer.  Is the ultra grey silicone like the factory sealer?  Not looking forward to this but need to get in the mood to do it.

two things... clean it with some brake cleaner.. before you are ready to take it apart.. i like the autozone brand brake cleaner...  smear a little more of your black silicone sealer on top. of the gap..  it does not take a lot.. and if you pack it in with your finger tip..  you can wipe off excess..  nobody  but you and i will know..

second thing..  do you have one of the fuel pump testers that is also a vacuum gauge???  30 inches of mercury, 15 psi??  get out adaptors and hook it to your engine oil dipstick.. rev the engine a few times..  or take it around the block.  make sure that you are NOT building any crankcase pressure or vacuum..     if you place your hand over the crankcase breather opening you should get vacuum almost instantly at idle..  slow build up though..  pull hand away after a few seconds and you should get a POP.. like some waiters did in the movies..

if you have a  hand held digital tachometer..  checking the PCV calibration .. if you are warmed up at idle..  squeeze or block the PCV flow at the end of the PCV valve..  your idle should reduce 50 to 70 RPMs..


if you are building crankcase vacuum.. or crankcase pressures.. you will blow not just the intake end seals out.    you will also want to retorque your intake manifold bolts carefully.. starting at the middle also..

when you are pulling the intakes off.. do you guys preset the engine to TDC#1 before you pull the distributor???  i go as far with electronic ignitions as turning the motor until the timing mark on the damper is close.. and looking at the reluctor poles and the pick up coil poles and slowly turn the crank in normal direction of rotation. until the poles lineup.. i then look down at the crank and see where the timing mark is.. thats going to be where the timing was set at..  now i can remove the distributor.. and what ever else.. drop it back in.. even if i have to bump the engine over two turns while it drops on the shaft. can then reset the damper position.. turn the housing to align the poles.. lock the distributor down.. reach thru the window and start the engine..  no more turning the distributor to get the timing close enough to get the engine started..    i do the same with points type.. i turn the crank till the points are just about to open.. and i have it..

hint.. with points. set the damper.. turn the distributor until the points are just about to open.. you can verify this.. by turning the rotor.. that first fragment of turn should make the points open..


and if anybody who reads this.. ever runs across one of the little bit larger than a checker game piece PCV flow tester..   clear plastic top with a ball inside like a mini roulette game.. and its only a few bucks.. i would love one..

[34ford]

Permatex product, "The Right Stuff".  Hooley uses it on his engines and from what I've seen it's the best RTV type sealer around.  I haven't put an engine together lately but when I do I'll use it.

Thanks George,  That's looks like some good stuff.

[purplepickup]

Thanks George,  That's looks like some good stuff.

It's like stepping up to Gorilla tape after using generic duct tape.  If you use it I'd bet you'll never have a leak there again.  It might be overkill but sometimes that's a good thing.

[Arnold]

What do you guys use for the ends on an intake manifold for sealer. I used the black gasket sealer and now have a leak on the front with only 3500 miles on the engine. It is a zz4 crate motor with the aluminum intake. I roughed up the surface on the block before I installed it. I do have a pvc valve on the passenger side and a breather on the driver side. I hate leakers.

Thanks

  There were some engines that were notorious leakers. They seemed to start leaking early..and then the fixes never lasted even as long as the first one.Even looking at the end gaskets..ya..this needs to be trimmed.And these were the new or replacements.
 Dark ages..pre-silicone.

  I remember fixing a leaker(notorious leaker)
and it leaked again..and someone who obviously knew a lot more about this than I did..could not believe that I was even using those end seals.
  I
 I was in the middle of this when the "Know It All" showed up.
 He even offered to do it..and said that is what he does now.

  Throw away those end seals. Even cheap hardware silicone..clean both sides with lacquer thinner..set up a good bead..let it sit..maybe 5 min or so max..stick it together..leak gone.

  I could not believe it that I had this leaker tamed

  WHERE :?: was silicone when I had British Motorcycles.

[34ford]

This crate motor has no gaskets on the ends. It is sealed with silicone or some grey colored material. Have some big hypodermic needles & syringes they use here at the lab for autopsy's so might fill one of them up with some and see if I inject it in the 2 leaking spots. It might cure it till I can fix it this winter. Worth a try.

[papastoyss]

The key to preventing leaks w/ silicone is clean, clean,clean. I clean the surfaces w/lacquer thinner, throw down the rag, get another one & do it again. Assemble the parts, finger tighten the bolts, let the goop cure before tightening the bolts. Using this method I've even had SBC's that the valve cover gaskets didn't leak!  Oh.btw, don't stick the thinner rag in your back pocket!!

[Beck]

Permatex product, "The Right Stuff".  Hooley uses it on his engines and from what I've seen it's the best RTV type sealer around.  I haven't put an engine together lately but when I do I'll use it.

I agree "The RIght Stuff" comes highly recomended, but any can fail. Twio different years I have been in the pits with Hooley repairing the 974 due to it leaking oil from the rear of the intake.
I just put a lower intake gasket on a GM 4.3. The Felpro gastket set came with the sealant for use on the front and rear, so that's what I used.

[34ford]

I picked up the gaskets yesterday and it comes with a small tube of Prematex black. probably will tackle it this weekend.