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Blown Head Gasket- spark plug analysis!?!

  • Thread starter Thread starter joshua.y
  • Start date Start date Oct 12, 2004
J

joshua.y

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Aug 27, 2004
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Oct 12, 2004
#1
  • Oct 12, 2004
  • #1
These three pics are from the cylinder with the blown head gasket. The top of the piston had been steam cleaned





This cylinder has the same crusties (as seen on the spark plug) on the top of the piston. The head gasket was intact in this area.




This plug is from a 'normal' cylinder.




All plugs are Autolite 103's. I was running 16 degrees with milled GT-40Ps (.050), Cobra intake, gears, exhaust, stock cam... I know I was begging for a blown head gasket and I obviously found detonation. The car ran a 13.6 @ 105 with the HGs and plugs in this condition.

What is that build up on my spark plugs?
 

IndyBlk5.0

New Member
Nov 24, 2003
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New Whiteland, IN
Oct 12, 2004
#2
  • Oct 12, 2004
  • #2
That sucks bro, hope it all works out
 
8

88gtvertboy

New Member
Aug 16, 2004
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maple valley wa.
Oct 12, 2004
#3
  • Oct 12, 2004
  • #3
joshua.y said:
These three pics are from the cylinder with the blown head gasket. The top of the piston had been steam cleaned





This cylinder has the same crusties (as seen on the spark plug) on the top of the piston. The head gasket was intact in this area.




This plug is from a 'normal' cylinder.




All plugs are Autolite 103's. I was running 16 degrees with milled GT-40Ps (.050), Cobra intake, gears, exhaust, stock cam... I know I was begging for a blown head gasket and I obviously found detonation. The car ran a 13.6 @ 105 with the HGs and plugs in this condition.

What is that build up on my spark plugs?
Click to expand...
You have been burning coolant, that is for sure. That is what those deposits are on your plugs.
 

Fishhawk

New Member
Jun 10, 2004
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Michigan City, Indiana
Oct 12, 2004
#4
  • Oct 12, 2004
  • #4
Sorry about the head gasket, but thanks for the pics. They just confirmed to me that I don't have a bad head gasket. What looked like oil in my antifreeze must just be crap from the radiator. Plugs look good, plus no antifreeze in my oil.
 
J

joshua.y

New Member
Aug 27, 2004
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Oct 12, 2004
#5
  • Oct 12, 2004
  • #5
I also found some crusty build up in the number three combustion chamber. So the build up is definitely burnt coolant? or maybe oil?

Full list of mods are in the sig.
 
J

joshua.y

New Member
Aug 27, 2004
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0
Oct 13, 2004
#6
  • Oct 13, 2004
  • #6
Does anyone have anything to add?
 
J

joshua.y

New Member
Aug 27, 2004
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0
Oct 13, 2004
#7
  • Oct 13, 2004
  • #7
anyone?
 

nito88stang

Founding Member
May 23, 2002
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Fullerton, California
Oct 14, 2004
#8
  • Oct 14, 2004
  • #8
resize those pics and ppl might actually stick around to see them
 
J

joshua.y

New Member
Aug 27, 2004
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Oct 14, 2004
#9
  • Oct 14, 2004
  • #9
nito88stang said:
resize those pics and ppl might actually stick around to see them
Click to expand...

good idea
 

jrichker

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Mar 10, 2000
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Dublin GA
Oct 14, 2004
#10
  • Oct 14, 2004
  • #10
A compression tester is the only good way to test for blown head gaskets. The compression tester is less than $35 at AutoZone.

A cylinder balance test by putting the computer into test mode and running the engine is the next best test.

Do a cylinder balance test to find clogged injectors or cylinders that aren't firing. Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure
 
J

joshua.y

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Aug 27, 2004
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Oct 15, 2004
#11
  • Oct 15, 2004
  • #11
Cool, thanks for the suggestion, jrichker!
 
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