blown 3 pairs of lower intake man gaskets need advice

Yellow302

Member
Mar 2, 2003
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NJ
ive been useing fel 1250 and have blow 3 sets of them, its getting expensive and frustrating. My heads are ported and boosted and arent getting a good enough seal due to less material on a surface.

Are there any thicker or better gaskets i can buy, so my car stops this.
 
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gaskets around the ports, endseals are fine

was wondering the middle port of the heads that allow coolent through... should i use the cover gasket to block to coolent since i have an egr delete plat there so the air/coolent cant circulate?

or run the open one? im currently running the open or ring gasket.
 
The middle ports you mention are EGR ports, no water. Block them if you are not using the EGR. Check to make sure you have the proper gap at the front and rear, you want atleast .040 when it is tq'd down, if your bottoming out you are not getting the proper tq to the intake. Also depending on how much your heads were milled check to make sure your intake bolts on easily, if it is hard to get some of the bolts aligned you may have to slot the intake bolt holes, this is also very important to achieving proper tq.

Dump the end seals and use Permatex all the way across, front and rear. You could also upgrade to intake studs but the bolts should work just fine properly tq'd.

Mr.Gasket makes a 1/8" thick intake gasket but it has a 1262/1262R size port, I am not sure if they make a small port version. TFS has a thick intake gasket as well.
 
ive had better luck with the cork gaskets, RTV blows out little pin holes with boost the cork seems to hold. Ill be blocking that center port on the heads. If anyone has a better write up with pics on how to put the gasked on the head properly with either glue/silicon/rtv/i dont know, its just costing me way to much to keep pulling this thing and it never being right with stock ported non milled heads.

I bought these lower intake gaskets.

http://store.summitracing.com/partdetail.asp?part=MRG-5834&autoview=sku

Larger port design hoping that will get a better seal.
 
When I saw your thread title, the first thing I thought was something is not
aligning like it should due to block or heads being cut.

I mean ... You don't see that issue come up often :nono:

I like Ricks thought about using the China wall gaps to see how low the intake is
setting down to the block :nice:

btw ... I agree with you about the cork end gaskets ;)

Let us know what you find :)

Grady
 
Parts ordered ill tear is down, again, this weekend. Ill try to do it slow so i can find where the problem is this time...

If not ill be going with a thicker lower intake gasket and a even bigger port size and hope for a seal.

Is there anything i should put on the head before i put the gasket down? EDL-9000 or what ever it is... didnt get the can to read the instructions. But i def want to super glue this bastard down so it wont shift or move under boost.
 
The Ebrock gaskachinch works well but I still prefer Permatex around the water jackets and I do put a very small amount in the large flat areas to help keep the gasket still. Let it setup just a hair then put the upper and and make sure you are not pushing the gasket around as you tq it down.

Definitely check the end gaps (front and rear of the block where your cork seals go), most guys never check them and it can be the cause. If that is the case you can mill the intake a little to fix it.

Here's a link to the .125" Mr.Gasket http://store.summitracing.com/partdetail.asp?part=MRG-213&autoview=sku
 
Im wondering the gap on the china wall is a good 1/4 to 1/2 inch granted ive checked and there is no leaks there it just seems a little big, so how or where would i have the lower milled?
 
If you have that large of a gap I would say you need to have the sides of the intake milled around .080" at a guess to bring it down. You may also need to slot the intake holes so you do not bind the bolts when tightening.

How is the port alignment? Do you see a step going into the head?

Any good machine shop can mill the intake...
 
ok did everything by my self top to bottom in 6 hours.

found the lower bolts to be not to torque spec.

New install...
cork ends with permetex in each corner
lower gaskets with a biger port opening, permetex around the water jacks, and the can of glue on the back of the gasket and the top of the head. Let it sit and that thing wasnt moving after a while.

I even bought studs to drop the lower down straight and bought a new torque wench.

As i was torqueing the lower the back cork gasket slid out (glue wasnt setup yet) lucky i cought it and was able to slide it inplace and slowly retorque everything.

The felpro set came with glue on one side and was very dry and tacky and worked better than the MR. gasket set i bought.

I started the car to back it out side and im letting it sit till tomorrow before i start to drive it around and heat it up.



Possible causes.
-Bolts not torqued enough. (will have to retorque after couple heat cycles)
-Stock bolts. (replaced with new)
-Front right head bolt hole wasnt treaded properly needed to clean it out badly to get the proper torque reading.
-Found the ground to the block to be loose so i tightened it down (thanks to my friend)


End in all I could have just retorqued the lower and it may have fixed the problem. The gap between the block and lower is only 1/8 and is fine.

Praying tonight before i start it again tomorrow.
 
For what it is worth :D

Over the years, I've done countless intake swaps on SBF's with no probs
and here is how I've gone about it :shrug:

I use the cork China wall gaskets

I use yellow 3M Weather Stripping Adhesive to glue them to the top of the wall

I put a dot of RTV in each corner of the China walls

I use no gasket sealer on the side gaskets

I use 4 sections of all thread to guide the intake down nice and straight

I follow the standard torque pattern to tighten all bolts

I go to about 50% of the maximum tightness repeated times until all bolts
obtain even tightness which can be 3 or more times

I then go to my final tightness until all bolts are equally tight

After two heat cycles, I go over all bolts again to check for even tightness and
I might add ... I've always found several to be loose

Agree or Disagree with my methods :shrug:

I don't have leaks, or end gaskets blow out, or anything like that ;)

Grady
 
did everything you said except

After two heat cycles, I go over all bolts again to check for even tightness and
I might add ... I've always found several to be loose

I have an extra set of gaskets to replace the upper with the spacer, i hate having to pull all that crap just to re tighten

So i have to heat it up,

cool it down,

heat it up,

tear it open while warm? and re torque?
 
did everything you said except

After two heat cycles, I go over all bolts again to check for even tightness and
I might add ... I've always found several to be loose

I have an extra set of gaskets to replace the upper with the spacer, i hate having to pull all that crap just to re tighten

So i have to heat it up,

cool it down,

heat it up,

tear it open while warm? and re torque?

Here is the deal on the bolts loosening up :)

After the motor heats up and cools down a few times ......
That aids in the gaskets to become compressed :(
thus
The clamping force is gonna be less :eek:

By two heat cycles, I just mean after a couple of times the motor has
reached normal temp and completely cooled down. Then, I just check
all the bolts when it has cooled for the second time.

Grady
 
perfect, i woke up early to get the first idle till warm session in.

lucky for me its 40 deg out so it will cool down fast.

I guess I should say its not like I don't drive the car or anything like that
when I'm talking about getting in two heat cycles.

I just don't beat on it or anything like that during those first couple of
shake down runs :nono:

You know ... :) after a major job like that :crazy:

Its always good after a short while of operation to pop the hood and give
everything a second look for vacuum/coolant leaks, loose bolts, and that
kind of thing ;)

Just being thorough
and
Paying attention to the details

Thats all I'm trying to get across here :D

Grady
 
ok well the intake and the car is running good. but my car is still drinking coolant. its going right into the oil and steam is pouring out of my valve covers.

All of this has been after the HCI install.

I see some wet marks around the top of the timing chain cover by the dizzy. But somehow coolant is flowing into the oil with easy, and this is the 4th time ive done the lower intake so ima have to say its not that.

What else could it be?