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Engine Head Gasket Water Jacket Holes

  • Thread starter Thread starter stang89bidges
  • Start date Start date Jan 4, 2015

stang89bidges

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Mar 14, 2014
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Fort Worth Texas
Jan 4, 2015
#1
  • Jan 4, 2015
  • #1
Head gaskets blown 4 times in 6 months. I'm at wits end and empty pockets.

I noticed the head gaskets have tiny holes over water jackets. Why are they so much smaller than block?

Also, there is a hole in the front of block that is blocked by new head gaskets? Looks like a water jacket. I will post pictures in next post soon.
 

stang89bidges

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Jan 4, 2015
#2
  • Jan 4, 2015
  • #2
 

Micheal Nadeau

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Dec 30, 2013
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Jan 4, 2015
#3
  • Jan 4, 2015
  • #3
When the headgasket went the first time, did it over heat? Have the heads been checked? By chance are you buying head gaskets for E7 heads and you have GT-40's?
 

stang89bidges

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Jan 4, 2015
#4
  • Jan 4, 2015
  • #4
Yes, always overheats. First time took long time to figure out, started loosing water out the overflow. Kept refilling. Went on for months. Daily driver then. Heads got resurfaced but not checked for cracks. Using felpro 9333's.

First 3 times blow the gaskets never showed any signs of break or gasket malfunction. This last time it has a burn spot and break in gasket just above #7 cylinder next to water jacket.

Edit: Also first three times it always did same, no bad gasket that i could tell and just lost little bit of water through overflow. This time I recognized the signs so quickly I just knew and tore it down. Sure enough it had a bad spot for first time.
 
Last edited: Jan 4, 2015

stang89bidges

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Mar 14, 2014
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Jan 5, 2015
#5
  • Jan 5, 2015
  • #5
The bad spot above #7



The other side almost did same thing above #3. You can see bad spot forming.



This is the gasket where there should be a hole. It gives good shot of how large block hole is and how small the gasket hole is.

 
L

Lscam580

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Aug 27, 2014
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Grand Rapids Mi
Jan 5, 2015
#6
  • Jan 5, 2015
  • #6
I had same problem with one motor only to find out I had a crack in block, machine shop Magd the block and show the crack with ease. If your getting that much overheating after all that I'd go as far as tearing down the entire motor. Antifreeze and mains down mix well. I'd freshen it up and spend the cash for the magnaflux. They should be able to do block and heads for a hundred and a half or so
 

stang89bidges

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Jan 5, 2015
#7
  • Jan 5, 2015
  • #7
Oh and stock heads.
 
L

Lscam580

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Aug 27, 2014
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Jan 5, 2015
#8
  • Jan 5, 2015
  • #8
I do have a pair of stock heads I'd be willing to give you they have 100k miles on them but are in good shape
 

stang89bidges

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Mar 14, 2014
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Jan 5, 2015
#9
  • Jan 5, 2015
  • #9
I plan on taking the heads in first to be checked for cracks. If they come out ok I guess I will pull block out and take it in to be checked.

What about my original question, why are the gasket holes so small compared to the block? I understand they are just steam ports but still, makes me think they would stay cooler if the holes were bigger. Also that port that's blocked off by gasket is a mystery to me as well...

I have a pic of the original ford gaskets I took off the first time. They look the same as the ones I'm putting on, even the blocked off port I think. Makes me think its fine they are made this way but still would think if they are enlarged they could breath better??? I dunno. Hoping someone on here can explain this.
 

jrichker

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#10
  • Jan 5, 2015
  • #10
The Ford engineers specified what size holes the gaskets have and where they are to be placed. The designed the engine and know what they are doing, and what works and what doesn't.

Ford does not make gaskets, but farms them out to suppliers like Fel-Pro, who follow Ford's design specifications.

You got a Fel-Fro or other major gasket maker part, so don't worry about the position of the holes in the gasket.; install them according to the instructions. Some gaskets are marked this side up or front; be sure to install them that way.

Worry about things like getting the gasket surfaces as clean as possible, and using anti seize compound on the bolt threads and under bolt heads and nut faces. Use Teflon pipe dope on the short head bolts since they thread directly into the water jacket. Use a good torque wrench to tighten the bolts to Ford's specifications or the cylinder head manufacturer's specifications. If you did all that like you should, you don't need to wonder or worry.
 

mikestang63

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Aug 27, 2012
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Jan 5, 2015
#11
  • Jan 5, 2015
  • #11
silly question- what head bolts are you using and did you check the block deck for straightness.
 

jrichker

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mikestang63 said:
silly question- what head bolts are you using and did you check the block deck for straightness.
Click to expand...
Very good question: the ARP cylinder head bolts come with chamfered washers that match the chamfer on the bolt heads. Put the chamfered sides together to that they mate up. If you install the washers with the chamfer facing the cylinder head surface, you'll never get the head bolts to torque down correctly.
 

stang89bidges

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Jan 16, 2015
#13
  • Jan 16, 2015
  • #13
I used a straight edge and went cross pattern and straight with .015 feeler guage all over deck. Feeler never slid under the straight edge once.

I bought the following http://www.latemodelrestoration.com/item/M6051D50/Ford-Racing-Head-Gasket-Bolt-Kit-Mustang-79-95-50

I torqued them to ford original specs. After changing heads 3 times I never have cleaned the bolt holes with tap. FYI.

I just got my heads back from shop. Magnafluxed, cleaned up, pressure tested. They were flat with no problems.
 
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