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351W stock intake question... helP?

  • Thread starter Thread starter xoxbxfx
  • Start date Start date Dec 27, 2005

xoxbxfx

Founding Member
May 9, 2001
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Southlake, TX
Dec 27, 2005
#1
  • Dec 27, 2005
  • #1
Well, I have NEVER run into something like this. I have an early 69 351w 2v intake manifold. Got it bolted down and everything and I started to fill the coolant into the radiator then 4 holes in the intake started leaking. They are about 1" in from each corner just inisde of the corner intke manifold bolt holes. Anyone know what on earth they are for and how to fix the problem?? They are not tapped, no holes in the heads for it, and Im stumped.

Thanks
Tim
 

Red Barchetta

Founding Member
Mar 7, 2002
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Behind the Orange Curtain
Dec 28, 2005
#2
  • Dec 28, 2005
  • #2
What kind of heads are you running? If you have aftermarket heads, they probably only have 12 bolt holes, 4 have been eliminated where the water passages are. I'm runing some World Products heads on my 351W with an old-school Offenhauser dual port intake manifold that has the 16 bolt holes. I ended up just tapping the holes and plugging them with bolts coated in Permatex Aviation Form-A-Gasket and never had a leak.
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
3
77
lubbock, texas
Dec 28, 2005
#3
  • Dec 28, 2005
  • #3
yeah, after 76 i think Ford started using the 12 bolt intakes instead of the early 16 bolt intakes. you might be fine just filling the bolt holes on the intake with silicone, if you don't want it to look ugly you could cut the extra intake bolts off just below the head of the bolt and silicone that in as well.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
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37
Salt Lake City, Utah
Dec 28, 2005
#4
  • Dec 28, 2005
  • #4
Did you run a layer of RTV around the ports between the gaskets and mating surfaces?
 

xoxbxfx

Founding Member
May 9, 2001
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Southlake, TX
Dec 28, 2005
#5
  • Dec 28, 2005
  • #5
69Rcode_Mach1 said:
Did you run a layer of RTV around the ports between the gaskets and mating surfaces?
Click to expand...

nope... Im sorta wonding if the moron at Autozone gave me the wront intake gaskets but I really dont want to pull the intake just to buy new gaskets. Im gonna check the casting numbers on the heads but I believe they are stock 69 351w heads
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 29, 2005
#6
  • Dec 29, 2005
  • #6
xoxbxfx said:
nope... Im sorta wonding if the moron at Autozone gave me the wront intake gaskets but I really dont want to pull the intake just to buy new gaskets. Im gonna check the casting numbers on the heads but I believe they are stock 69 351w heads
Click to expand...

There's your problem, you need to pull the intake off, and put a thin bead of RTV around the coolant passages on the intake and cylinder head side, then tighten it down. This will seal the coolant and keep it from wandering.
 

xoxbxfx

Founding Member
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Southlake, TX
Dec 29, 2005
#7
  • Dec 29, 2005
  • #7
69Rcode_Mach1 said:
There's your problem, you need to pull the intake off, and put a thin bead of RTV around the coolant passages on the intake and cylinder head side, then tighten it down. This will seal the coolant and keep it from wandering.
Click to expand...


call me crazy but the last 5-6 motors we ahve put together we have never done that.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 29, 2005
#8
  • Dec 29, 2005
  • #8
It is good practice and necessary, I am surprised coolant has not leaked out and opened up a vacuum leak. If anything give it a shot and see what if there is no RTV on it. Might I also recommend putting a thick layer of RTV on the ends of the Intake instead of using cork end gaskets.
 

xoxbxfx

Founding Member
May 9, 2001
3,959
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Southlake, TX
Dec 29, 2005
#9
  • Dec 29, 2005
  • #9
69Rcode_Mach1 said:
It is good practice and necessary, I am surprised coolant has not leaked out and opened up a vacuum leak. If anything give it a shot and see what if there is no RTV on it. Might I also recommend putting a thick layer of RTV on the ends of the Intake instead of using cork end gaskets.
Click to expand...

lol..i dont use the cork gaskets
 
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