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  • Fox 5.0 Mustang Tech

Cometic Head Gaskets LEAKING!

  • Thread starter Thread starter soontobefastfox
  • Start date Start date Nov 2, 2007
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soontobefastfox

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Nov 15, 2005
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Nov 3, 2007
#21
  • Nov 3, 2007
  • #21
Mike92GT said:
You can still use studs with your heads if you decide to switch over. My Eddys also have the 1/2 head bolt holes. You just need the step washers / inserts that fit inside the holes in the cylinder head. I don't think it has been mentioned, but did you use thread sealant on the short head bolts?
Click to expand...

Yes I did use arp thread sealant on my short head bolts. Where did you get the studs you are talking about? Are they ARP?
 
M

Mike92GT

Founding Member
Jan 23, 2002
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#22
  • Nov 3, 2007
  • #22
ETA: Here is a link for the bushings I'm talking about. I did use ARP studs and bushings with mine, and they came with the bushings in the kit, just a different part#


http://www.trickflow.com/partdetail.asp?part=TFS-51400419&autoview=sku
 

1991vert

10 Year Member
Feb 27, 2004
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Nov 4, 2007
#23
  • Nov 4, 2007
  • #23
cometic head gaskets need a certain finish on the block. that's why a lot of people on here stay away. should've done your research
 

soontobefastfox

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Nov 4, 2007
#24
  • Nov 4, 2007
  • #24
1991vert said:
cometic head gaskets need a certain finish on the block. that's why a lot of people on here stay away. should've done your research
Click to expand...

Hmm that's interesting, I called Cometic while my block was being machined (brand new Ford 302 Sportsman) and asked them if there needed to be any special finish (also asked if they needed to be sprayed with copper), they said that it does not need a special finish or anything of that sort. I had the sportsman block re-decked so had a better smoother gasket mating surface. So please do not come into a thread and just accuse someone of not doing their research.

Oh and this is NOT just a Ford small block issue. My buddy had the exact problem as me with his 92 eclispe with cometic head gaskets.
 

soontobefastfox

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Nov 15, 2005
275
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Nov 4, 2007
#25
  • Nov 4, 2007
  • #25
Mike92GT said:
ETA: Here is a link for the bushings I'm talking about. I did use ARP studs and bushings with mine, and they came with the bushings in the kit, just a different part#


http://www.trickflow.com/partdetail.asp?part=TFS-51400419&autoview=sku
Click to expand...

Mike do those bushings go all the through the cylinder head?
 
M

Mike92GT

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#26
  • Nov 4, 2007
  • #26
No, they don't go all the way through. I'd say they go about 1/2" deep, maybe a little less. They basically just reduce the 1/2" hole down to 7/16"
 

soontobefastfox

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Nov 4, 2007
#27
  • Nov 4, 2007
  • #27
Mike92GT said:
No, they don't go all the way through. I'd say they go about 1/2" deep, maybe a little less. They basically just reduce the 1/2" hole down to 7/16"
Click to expand...

Ok that's what I thought. Do you know the ARP part number by chance?
 
M

Mike92GT

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#28
  • Nov 4, 2007
  • #28
If you want the complete set with the head studs AND the step washers I believe the correct ARP part # is 154-4005. I believe you can buy just the washers from ARP, but I'm not sure on the part number. (I'm pretty sure the washers that TFS sells are made by ARP)
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Nov 5, 2007
#29
  • Nov 5, 2007
  • #29
The bushings are PT 200-8598 $41.00 (sold in packs of 10/each)

Hope that helps....
 

soontobefastfox

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Nov 15, 2005
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Nov 5, 2007
#30
  • Nov 5, 2007
  • #30
Rick 91GT said:
The bushings are PT 200-8598 $41.00 (sold in packs of 10/each)

Hope that helps....
Click to expand...

Thanks Rick!
 

gcomfx.com

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Nov 5, 2007
#31
  • Nov 5, 2007
  • #31
1991vert said:
cometic head gaskets need a certain finish on the block. that's why a lot of people on here stay away. should've done your research
Click to expand...

You basically insulted everyone that's ever had a cometic gasket fail. Watch my video before you jump on the wrong bandwagon. My set failed INBETWEEN the layers. There isn't a smooth surface on the planet that they would have sealed up on.
 
M

Mike92GT

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#32
  • Nov 5, 2007
  • #32
You can get the TFS bushings in a 20 pack for $31 from Summit. That should save you $51 compared to ARP. I'm not sure why ARP wants $41 for 10?
 

soontobefastfox

Member
Nov 15, 2005
275
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Troy, Michigan
Nov 5, 2007
#33
  • Nov 5, 2007
  • #33
Mike92GT said:
You can get the TFS bushings in a 20 pack for $31 from Summit. That should save you $51 compared to ARP. I'm not sure why ARP wants $41 for 10?
Click to expand...

Interesting? I thought you said the TFS ones were ARP as well?
 

soontobefastfox

Member
Nov 15, 2005
275
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Nov 5, 2007
#34
  • Nov 5, 2007
  • #34
gcomfx.com said:
You basically insulted everyone that's ever had a cometic gasket fail. Watch my video before you jump on the wrong bandwagon. My set failed INBETWEEN the layers. There isn't a smooth surface on the planet that they would have sealed up on.
Click to expand...

I've got your back gcomfx!
 

1991vert

10 Year Member
Feb 27, 2004
1,103
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Ludlow, MA
Nov 5, 2007
#35
  • Nov 5, 2007
  • #35
gcomfx.com said:
You basically insulted everyone that's ever had a cometic gasket fail. Watch my video before you jump on the wrong bandwagon. My set failed INBETWEEN the layers. There isn't a smooth surface on the planet that they would have sealed up on.
Click to expand...

http://www.cometic.com/faq.aspx#q4

"A surface finish of 50 RA (roughness average) or finer, is recommended for a proper gasket seal. Anything rougher may conflict with the gasket design. "

right off their website. i'm building an engine right now using cometics.
 

gcomfx.com

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#36
  • Nov 5, 2007
  • #36
1991vert said:
http://www.cometic.com/faq.aspx#q4

"A surface finish of 50 RA (roughness average) or finer, is recommended for a proper gasket seal. Anything rougher may conflict with the gasket design. "

right off their website. i'm building an engine right now using cometics.
Click to expand...

Stop posting and look at my video. Nothing you are posting will stop a DEFECTIVE gasket that FAILS in between the layers.

Cometic even inspected the bad gaskets, admitted they had issues with them, then sent me FREE replacements. No questions asked. It had NOTHING to do with improper installation. Never have I said ALL cometics are bad. Never have I said NONE of them will seal. But it is confirmed they had production issues and were working on a solution.

My engine builder was instructed by cometic themselves to use a sealer the second time. The sealer was for the edges of the gaskets. Guess what, it seemed to have held. Interesting huh? Surface is the same, seals up after you coat the edges of the gaskets.

We'll confirm they actually held, when I get time to yank the engine out again. Until then, good luck. Maybe you won't be one of the few that gets bit from DEFECTIVE gaskets that are PROPERLY installed.

Now I know why I rarely venture out of the 94-95 section. Going back to my hole.
 

1991vert

10 Year Member
Feb 27, 2004
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Ludlow, MA
Nov 5, 2007
#37
  • Nov 5, 2007
  • #37
gcomfx.com said:
Now I know why I rarely venture out of the 94-95 section. Going back to my hole.
Click to expand...



k bai
 

gcomfx.com

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Oct 22, 2002
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#38
  • Nov 5, 2007
  • #38
Just remembered. I was invited here... Helping a fellow stanger is much more important than arguing with you.
 

soontobefastfox

Member
Nov 15, 2005
275
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Troy, Michigan
Nov 5, 2007
#39
  • Nov 5, 2007
  • #39
gcomfx.com said:
Just remembered. I was invited here... Helping a fellow stanger is much more important than arguing with you.
Click to expand...

Thanks!

Lets not argue! I just wanted to let people know my horror story and see if others had any other problems/experiences.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
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108
Chicagoland
Nov 5, 2007
#40
  • Nov 5, 2007
  • #40
gcomfx.com said:
Just remembered. I was invited here... Helping a fellow stanger is much more important than arguing with you.
Click to expand...

And a moderator set up the initial contact between the members who have had issues with the Cometic gaskets, so I'm glad it's been steered back to a discussion about a solution to the issue with facts. Let's please keep it that way gentlemen. Thanks Paul for coming over and helping out!
 
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