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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

To Rtv Or Not Rtv

  • Thread starter Thread starter mikestang63
  • Start date Start date Oct 23, 2015

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Oct 23, 2015
#1
  • Oct 23, 2015
  • #1
Curious as to what everyone's opinion is regarding intake gaskets and RTV.

Do you put
  • No RTV on the head to secure the intake gasket
  • RTV on the head to secure the intake gasket
  • No RTV around the water part
  • RTV around the water port on the head
  • RTV around the water port on the head and also around the water port on the intake gasket
  • RTV around the water ports and intake ports on the head

Again, just curious as everyone has there own methods. I'm old school andfor the last 30+ years have always put a very light smear of RTV around the water ports with no problems. Let's not turn this into a who's right and who'd wrong.
 

Boosted92LX

It's only an inch or two. What's the big deal?
15 Year Member
Dec 19, 2010
5,721
4,244
224
Oct 23, 2015
#2
  • Oct 23, 2015
  • #2
Rtv on water ports and ends on the block.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,944
224
Massachusetts
Oct 23, 2015
#3
  • Oct 23, 2015
  • #3
RTV on ends of block, around water ports and I use the cork gaskets. I also use two studs wit hthe heads cut off to guide the lower intake down onto the block. makes it so much easier.
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
Nov 29, 1999
10,641
8,909
234
Birmingham, al
Oct 23, 2015
#4
  • Oct 23, 2015
  • #4
What are you talking about? My gaskets are RTV.
 
Reactions: Boosted92LX

v8stang289

15 Year Member
Apr 22, 2008
136
116
74
Oct 23, 2015
#5
  • Oct 23, 2015
  • #5
I usually rub a thin coat of rtv around the water ports, I try to work it in to the surface of the gasket. For the china rails I like the silicone gaskets that felpro has over the cork ones or rtv.

I know one engine builder with 40 yrs experience that glues the intake gaskets to the head with yellow weatherstrip adhesive. It works really well and they dont move, but teardown sucks if you have to go back in one.
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
Nov 29, 1999
10,641
8,909
234
Birmingham, al
Oct 23, 2015
#6
  • Oct 23, 2015
  • #6
What is a China rail, and when did that reference start?
 

v8stang289

15 Year Member
Apr 22, 2008
136
116
74
Oct 23, 2015
#7
  • Oct 23, 2015
  • #7
The rails along the front and rear of the engines valley. Don't know when it started. I've always heard them referenced as china rails/walls. I guess in reference to their visual similarity to the great wall of china?
 

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
2,560
1,146
184
Georgia
Oct 23, 2015
#8
  • Oct 23, 2015
  • #8
I have read that reference several times here lately.

Joe
 

A5literMan

At least it is lumpy...
5 Year Member
Jul 30, 2011
4,674
2,343
194
Illinois
Oct 23, 2015
#9
  • Oct 23, 2015
  • #9
I've used the rtv like you Mike(not mad Mike-he be crazy) in the past. My buddy only uses it at the ends and a little film around the water ports while using some adhesive on the head to keep it in place.
 

Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
9,531
5,187
224
Oct 24, 2015
#10
  • Oct 24, 2015
  • #10
I use Permatex gasket shellac on the heads, then set the gaskets in place, then a thick bead of black RTV on the ends of the block. I've never had one leak doing it that way.
 

Chuckman

GTFO you fat, heavy bastard
15 Year Member
Oct 21, 2005
1,604
1,002
173
st. louis, mo
Oct 24, 2015
#11
  • Oct 24, 2015
  • #11
i use a little spray gasket adhesive (Gasket Sealants : Permatex® High Tack™ Spray-A-Gasket™ Sealant) on the gaskets to keep them from moving (the 1250s3's dont have the tabs that lock into the headgaskets), and then ultrablack JUST on the end rails. rtv around the water ports will just make the sealing surfaces uneven there, and you want as FLAT, SMOOTH, and EVEN of a sealing surface as you can get.

use 4 pieces of all thread in the corner bolt holes to help center the intake so theres even less change of gasket squirm.

i use the same process on the pita timing cover and water pump gaskets. havent had a leak on any of em since i started using that spray adhesive (and i got a new, non-beat-to-hell timing cover).
 
Reactions: A5literMan
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