I have removed my intake to clean things up and hopefully correct a problem. But I have not done this since 1978 when I was a kid and then I did not sweat the details. Is there a preferred gasket manufacturer I should go with or is the Fel-Pro listed on NPD as good as any?
Is there anything I should do special when installing the gaskets? Should I put anything on the gaskets or the mating surfaces? Should I put something in the joints between the side gaskets and the end gaskets?
Thank you,
Corey
Fel-pro.
I just installed my GT350 aluminum intake last year. I used the fel pro gaskets and the cork ends. Clean the intake and heads very well and make sure they are smooth. I used a DA sander on the intake side to clean it up. Use weatherstrip adhesive to glue the cork pieces to the block first and let dry. I also used the copper spray on the side gaskets to help hold them to the block. Black RTV on the 4 spots that the cork meets the gaskets. About the size of a dime or less. I believe most people advise using a thin layer of RTV around the water jackets as well. Make sure the intake drops straight down over the studs and doesn't move front or back while you start the torque sequence.
One of the issues here is that there are two different cork thicknesses. The original one was thinner then virtually everyone you get in anyone's "kit" including Fel-pro,
The expensive issue is going to be that the COBRA aluminum intakes can be fragile on the rear two bolt holes and often we see repaired manifolds were those tabs have been cracked or even snapped off.
In order to use the current supplied cork ends you are going to need to compress them and I don't know how that you do that without clamping them down with the manifold?
If you want to risk that, that's up to you but that can be a VERY expensive mistake to damage that intake and I'll also point out that the rear water ports are where the gaskets like to leak sometimes internally where you don't see it.
You CAN use the cork ends but all things considered it is MUCH safer to trash them and just RTV the ends. However, it's your choice and neither is a mandatory decision. It's just you who has to regret not going the safer route.
Quote from: shelbydoug on February 14, 2021, 09:55:23 AM
One of the issues here is that there are two different cork thicknesses. The original one was thinner then virtually everyone you get in anyone's "kit" including Fel-pro,
The expensive issue is going to be that the COBRA aluminum intakes can be fragile on the rear two bolt holes and often we see repaired manifolds were those tabs have been cracked or even snapped off.
In order to use the current supplied cork ends you are going to need to compress them and I don't know how that you do that without clamping them down with the manifold?
If you want to risk that, that's up to you but that can be a VERY expensive mistake to damage that intake and I'll also point out that the rear water ports are where the gaskets like to leak sometimes internally where you don't see it.
You CAN use the cork ends but all things considered it is MUCH safer to trash them and just RTV the ends. However, it's your choice and neither is a mandatory decision. It's just you who has to regret not going the safer route.
+ 1 on ditching the cork end seals and going with RTV. I've noticed that the aftermarket intake manufacturers (Edelbrock, Weiand) tell you to discard the cork end seals and use RTV in their instructions.
Terry
Some restorers take the cork end pieces and carefully slice them to half thickness and use them that way so that they can retain the factory type cork end pieces. This works for the majority of instances . More work for sure compared to use just the RTV. This would only be more for the person concerned about wanting a solution for a effective yet original looking installation.
Can I presume that SA used cork end seals during the original manifold installation?
How did that work out for them?
Quote from: 68countrysedan on February 14, 2021, 03:38:49 PM
Can I presume that SA used cork end seals during the original manifold installation?
How did that work out for them?
Yes but the original cork ends seem to be thinner, as Bob says, by about half.
I recently tried to go back to them and wound up doing the manifold installation three times.
First it leaked water, then oil and had a vacuum leak.
I was convinced the water and oil, was a bad head gasket which was a $90 Cometic one. Nope. Freakin' cork is what it was. It was all in the back against the firewall too so instead of it taking normal time, it took six times the effort since I had to do everything twice AND change the head gasket.
I even shimmed up the head bolts thinking they were too long and bottomed out?
Dumb, dumb and dummer.
A wise man will learn from the folly of others so as not to repeat it. Some of us become wise,,,sometime later. ;)
I know the difference between self deprecating and self defecating. I'm embarrassed to admit, sometimes... not always, exactly which apples best to my case?
I just offer my experiences in order to save you from the same mistakes. But we can change the names in order to protect the innocent?
Quote from: 68countrysedan on February 14, 2021, 03:38:49 PM
Can I presume that SA used cork end seals during the original manifold installation?
How did that work out for them?
You presume correctly regardless of if Ford or SA installation of the intakes. Unlike fresh engines back in the day the engines of today many times have been rebuilt more than once. During rebuilding it is not uncommon for heads and blocks to be resurfaced. The resurfacing of one or the other or both complicates the fitment of a gasket on the front or back of the intake each time. That is why it is more of a issue now then back when the engines were first put together.
This all sounds like really good advice. I really appreciate the help. I would really like this to work the first time. Would the permeated ultra black RTV be a good choice for the ends?
Corey
Quote from: Corey Bowcutt on February 14, 2021, 04:24:54 PM
This all sounds like really good advice. I really appreciate the help. I would really like this to work the first time. Would the permeated ultra black RTV be a good choice for the ends?
Corey
If using the RTV I think it would. Basically any RTV will give good results but that one I have used with good results.
Fel-Pro sell sheets of cork in various thickness. They refer to it as rubberized cork-it looks exactly like cork and was designed for us doing restorations. The Fel-Pro PN's are 3005, 3006 etc. You can get on Rockauto or Amazon.
The reason cork gaskets can be problematic is during engine rebuilds the block decks and heads get milled which draws intake mating surfaces away from intake and manifold can't go down far enough with fixed cork gaskets. Skilled engine builders will machine bottom of intake to compensate. On a FE this will allow valve cover to seal better because top of intake and head will be flush
Quote from: TLea on February 14, 2021, 06:07:48 PM
The reason cork gaskets can be problematic is during engine rebuilds the block decks and heads get milled which draws intake mating surfaces away from intake and manifold can't go down far enough with fixed cork gaskets. Skilled engine builders will machine bottom of intake to compensate. On a FE this will allow valve cover to seal better because top of intake and head will be flush
That is certainly true but not the entire answer. The current aftermarket, including Felpro seem to be just too thick even on reassembling an intake where nothing has been milled or resurfaced.
I think it's important to illustrate the "risks" involved in attempting to use them and the alternatives so that those in need can make an informed decision.
Quote from: Bob Gaines on February 14, 2021, 04:11:23 PM
During rebuilding it is not uncommon for heads and blocks to be resurfaced. The resurfacing of one or the other or both complicates the fitment of a gasket on the front or back of the intake each time. That is why it is more of a issue now then back when the engines were first put together.
Quote from: shelbydoug on February 15, 2021, 10:03:28 AM
Quote from: TLea on February 14, 2021, 06:07:48 PM
The reason cork gaskets can be problematic is during engine rebuilds the block decks and heads get milled which draws intake mating surfaces away from intake and manifold can't go down far enough with fixed cork gaskets. Skilled engine builders will machine bottom of intake to compensate. On a FE this will allow valve cover to seal better because top of intake and head will be flush
That is certainly true but ......................
Not to be at odds with anyone, but this is not correct :o
The intake face of the cylinder head is machined at 90° to the deck surface, and each of these cylinder head intake mounting surfaces are 90° to one another, therefore the overall intake meeting surfaces do not change in distance from one another with the proper machining of the cylinder head or block decking surfaces. ;)
Now, an effect of the cylinder head intake faces siding downward in alignment under the intake manifold, but still in the same plane of parallelism and distance, will be witnessed as either of the decks are surfaced. If in order to correct this to some degree, one then machines or surfaces the intake manifold faces so as to cause it to "sink" in its' relationship to the cylinder head faces this correcting for better inlet port and bolt hole alignment (except in the S.B.F. as the bolt holes for the intake manifold retention are vertical & note that those with bolt holes at divergent angles may not recover simultaneously with other alignment concerns), and this does change the position of the intake manifold in its' relationship to the cylinder block "china-wall". :)
And before someone chooses to blast me out of the water, think-about-it! ::)
Scott.
"I" feel it is FAR more important to NOT BE IN A HURRY. I typically torque the inner bolts ( not the outer four )and walk away for 24 hours. That lets cork end seals take a set . The the next day , I torque "all" of them. The next day I check them for torque loss again. I do this again after the engine starts and cools until they do not move. Yes it's allot of "fussing" but it works. I use silicone "sparingly" after seeing lumps lodged it the oi pickup screen on disassembly of many engines.
Randy
Quote from: pbf777 on February 15, 2021, 11:35:39 AM
And before someone chooses to blast me out of the water, think-about-it! ::)
Scott.
No blasting, you are correct. You explained it better than I did. We are essentially saying the same thing. Machining heads and block will altar intake to block fit
Agreed Scott and "sometimes" NOT machining the sides of the manifold "raises" the ports to the heads. I have seen "gasket matched" heads done by "home enthusiasts" that have poor part to part match when installed. I use a bore o scope to check it out.
1) 100% agree with Randy (GT350HR) to not be in a hurry. Do your self a favor and take your time.
2) When installing my intake, I went to the hardware store and bought two bolts that are the same size as the Intake Manifold bolts. I cut off the heads of the bolts essentially turning them into studs. I installed both these studs on the same side of the engine and used them to A) help locate the intake and B) eliminate any back-and-forth movement of the intake as I lowered it into place. This really helped position the intake perfectly the first time and helped get a good seal at the front and rear of the intake where either the cork or the gasket material is used.
3) Corey, I chose to go with the Permatex Ultra Gray rather than the Ultra Black. I think they are exactly the same, but cosmetically, the Ultra Gray is less noticeable than the Ultra Black against the aluminum color of the intake. But either should work well.
Jeff
Quote from: JWH on February 15, 2021, 05:25:49 PM
1) 100% agree with Randy (GT350HR) to not be in a hurry. Do your self a favor and take your time.
2) When installing my intake, I went to the hardware store and bought two bolts that are the same size as the Intake Manifold bolts. I cut off the heads of the bolts essentially turning them into studs. I installed both these studs on the same side of the engine and used them to A) help locate the intake and B) eliminate any back-and-forth movement of the intake as I lowered it into place. This really helped position the intake perfectly the first time and helped get a good seal at the front and rear of intake where either the cork or the gasket material is used.
3) Corey, I chose to go with the Permatex Ultra Gray rather than the Ultra Black. I think they are exactly the same, but cosmetically, the Ultra Gray is less noticeable than the Ultra Black against the aluminum color of the intake. But either should work well.
Jeff
To add - some choose to paint the gasket white to mimic the color of the typical Ford intake gaskets of the time period. This does not make it look exact but gives a more period look all things considered.
Quote from: gt350hr on February 15, 2021, 05:03:28 PM
Agreed Scott and "sometimes" NOT machining the sides of the manifold "raises" the ports to the heads.
There have been a few instances where I wanted to relocate the intake manifolds' inlet port center-line in relation to the cylinder head and in doing so I have either manufactured spacer plates mechanically fastened to the intake or cylinder head face, or weld built-up the intakes' faces with the required material, porting and surfacing. :)
Scott.
Quote from: gt350hr on February 15, 2021, 05:03:28 PM
Agreed Scott and "sometimes" NOT machining the sides of the manifold "raises" the ports to the heads. I have seen "gasket matched" heads done by "home enthusiasts" that have poor part to part match when installed. I use a bore o scope to check it out.
You have as many original Ford parts as anyone I've know. Do you have an original Ford service set that you can measure the thickness of the cork with?
Randy, has more then I but I happened to have a couple packages handy.The smallblock cork ends measured at .212 and the BB measured .187 . Unfortunately I didn't have any modern intake gasket ends to compare to.
Quote from: Bob Gaines on February 15, 2021, 11:39:37 PM
Randy, has more then I but I happened to have a couple packages handy.The smallblock cork ends measured at .212 and the BB measured .187 . Unfortunately I didn't have any modern intake gasket ends to compare to.
I don't have any original Ford or Ford service parts, just Felpros. Want those?
As of the old originals, if others' are anything like those that we've piled up here for several decades, and at this point in time they're a little crispy, somewhat brittle and lacking the pliability originally intended to provide proper sealing; I wouldn't advise their use unless one is just determined to have "original stuff" because it very likely may prove to be "bad stuff"! :o
My suggestion as far as for the intake gaskets would be to purchase the Mr Gasket Co. grey composite gaskets, profile the perimeter, apply coloration and markings as deemed required to match or simulate the originals, and be more confident of a successful installation, even if it isn't absolutely "original" in origin. ;)
Sorry, I'm just a function first guy, perfection in appearance is important, but just not before proper function. Remember, of the two women at the bar, the "10" just might not be the best one to take home! ::)
Scott.
Doug ,
Bob's set of NOS '67s are already packed so I can't measure them . Maybe Jeff can check his. IIRC they are 3/16ths and will "crush" to 1/16th.
Randy is correct - uncrushed 0.187 thisk...
First qualification: these are Felpro (recent) not Ford. They measure .19475" uncrushed.
The closest I can come to measuring them crushed are similar Felpro valve cover gaskets on -03074's engine as it sits in the shop.
Here's the picture. There is NO crush apparent on those gaskets and the cover IS torked down.
Second qualification: I did not remove the valve cover to measure the crush.
Observation: the observed crush on the valve cover gasket is similar to my attempt at the intake installation which is essentially zero crush and as a result caused a bunch of unexpected results such as a vacuum leak, oil leak, water leak.
The actual space that is siliconed on my small block is less then half of what this original thickness is. Did I measure it yet? No. Do want that number?
My conclusion BEFORE any of this discussion "errupted". DON'T USE THE 'FREAKIN' CORK".
Now considering how stubborn this group is, and the "don't tell me WTF to do" attitude of many, "go your own way" but if you aren't planning on showing in Concours, do you need the aggravation and abuse of making these things work, especially considering not just the leaking possibilities but risking breaking the intake to make them work?
You could just take a mallet and beat the intake manifold down until the cork is crushed?
Is it possible the factory soaked the cork in something to soften them before assembly?
If you can get them to work, then "you're a better man then I Gunga Din"? I just don't see where any of this effort is worth it? Take the points deduction.
...pssst! I can't crush these to 1/16 in a vice! Just tried it. Nada.
Valve cover gaskets are "usually thicker than end seals" ( .250 in some cases)
Quote from: gt350hr on February 16, 2021, 01:28:18 PM
Valve cover gaskets are "usually thicker than end seals" ( .250 in some cases)
The Felpro's that I have, SB and FE, both start new at the same thickness. They don't compress easily.
I think that Bob's comment about "some people" cutting them in half, i.e., reducing the thickness by half to start out with, is a telling observation?
Any way anyone wants to go with it is ok. They are now informed of others experiences, should not be surprised with similar results and that there are alternatives to the original corks if it doesn't work out well initially.
I think that is all any of us tried to say?
FYI, starting at the full .195", I WAS able to compress the Felpro cork's in a vice down to .137". 1/8" is .125" and unnecessary to compress it that far. It is flexible and springs back when released.
The measured space between the installed intake bottom and the top of the block I have is .1435". So it doesn't need to compress fully to the minimum thickness of .137".
So according to those numbers, the cork gaskets that I have, which are Felpro SHOULD BE NO PROBLEM to use. They are working exactly as they should be.
The operative word is SHOULD be. Why I had issues with them is anyones guess. I' don't know and I would say that I should not have, but I did.
Silicone was the solution for me.
On the 428 (as I pictured) I just painted the RTV blue with matching engine paint. Only the purest of the purests would protest? They should find something else to worry about I think?