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Engine Hg Blown, Possible Cause, Look At This Pic Please!

  • Thread starter Thread starter madspeed
  • Start date Start date Sep 27, 2013

madspeed

Colonel Mustard
Founding Member
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a van down by the river
Sep 27, 2013
#1
  • Sep 27, 2013
  • #1
Hey guys, as i posted in another thread, I've recently discovered a blown headgasket at cylinder number 5. No oil in coolant, and no coolant in oil, it was only driven about 3 miles when i heard what sounded like the header gasket leaking. While investigating a bit, i noticed the head stud at that cylinder was wet with oil, and inside the exhaust chamber it was pretty black with a bit of oil buildup, as both can be seen in this pic. The other cylinders look different, just like normal exhaust pipes look.


View attachment 124088

You can see the metal sticking out where the gasket blew out in this pic.

View attachment 124089

What is this telling me??

THANKS
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
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Sep 27, 2013
#2
  • Sep 27, 2013
  • #2
Really doesn't look like a big deal. I would pull the heads have them resurfaced install some new gaskets and rock and roll.

Things to consider after you fix it. How much boost? How much total timing under full boost? Where is the a/f under boost? Any signs of detonation? How do the plugs look after a WOT pass?
 

madspeed

Colonel Mustard
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Sep 27, 2013
#3
  • Sep 27, 2013
  • #3
Boost is 10 psi, total timing i'll have to check on, afr under boost is 11.5- 11.6, no signs of detonation, plugs look normal, even the one pulled from that cylinder. Seems to die off a bit around 5000 rpms, but no dropoff in boost or afr

what would cause the oil pooling on the exterior of the stud? Maybe a bad gasket to begin with or improper torquing?
 

Casey2552

Member
Sep 16, 2013
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Taylor,mi
Sep 27, 2013
#4
  • Sep 27, 2013
  • #4
To me it looks like a bad valve seal or guide and header gasket went bad and blew the oil on to the bolt ,, ????
 

madspeed

Colonel Mustard
Founding Member
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a van down by the river
Sep 27, 2013
#5
  • Sep 27, 2013
  • #5
header gasket did not blow, sounded like it, but was fully sealed when removed and i found the hg sticking out as pictured
 

Casey2552

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Taylor,mi
Sep 27, 2013
#6
  • Sep 27, 2013
  • #6
Oh yeah I see now , got to take it apart to find out , hopefully nothin maybe just a bad head gasket damaged maybe when installed and a new one will be good if your lucky but if it was mine , lol it would have a hole In the piston and scoured cylinders , that's my luck
 

Casey2552

Member
Sep 16, 2013
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Taylor,mi
Sep 27, 2013
#7
  • Sep 27, 2013
  • #7
MIt looks like there's a lot of oil build up in there , I think there has to be a problem in valve , maybe on top side " seal or guide " or oils comin threw the bottom of the valve , I think that would mean possible ring failure in that cylinder..also if the pushrod bent and valve was not opening could that cause excessive presure for that cylinder just a thaught
 

Casey2552

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Sep 16, 2013
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Taylor,mi
Sep 27, 2013
#8
  • Sep 27, 2013
  • #8
I would pull valve cover and rotate motor over and see that rockers are working properly before you disassemble , making sure the lift and duration appear to be the same as other cylinders
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
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Sep 28, 2013
#9
  • Sep 28, 2013
  • #9
@Casey2552 where are you coming up with all of this? I seriously doubt there is a cam problem and what does that have to do with a head gasket? The valve seals leak oil onto the outside of the head stud?? Am I reading this right? Certain valve seals in my heads have been removed for a reason and i have no trouble....
 

Casey2552

Member
Sep 16, 2013
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Taylor,mi
Sep 28, 2013
#10
  • Sep 28, 2013
  • #10
Geuss you know what your talking about , here's a cookie
 

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MikeH686

Mine is only two inches though.
10 Year Member
Oct 11, 2011
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Sep 28, 2013
#11
  • Sep 28, 2013
  • #11
^^dic k thats why @84Ttop has a boosted vehicle and talks from experience bolst plays alot of roles in the dilemma if it was a bad seal he would have a blue smoke
 
Reactions: f8tlfiveo and 84Ttop

Casey2552

Member
Sep 16, 2013
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Taylor,mi
Sep 28, 2013
#12
  • Sep 28, 2013
  • #12
Well then I guess only your opinions matter , no big deal I didn't come on here to argue with to guys that are good at what they do
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
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Sep 28, 2013
#13
  • Sep 28, 2013
  • #13
Casey2552 said:
Geuss you know what your talking about , here's a cookie
Click to expand...
At least it wasn't oatmeal raisin...
For the future I prefer Doritos @MikeH686 @TOOLOW91
 
Reactions: TOOLOW91

Casey2552

Member
Sep 16, 2013
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Taylor,mi
Sep 28, 2013
#14
  • Sep 28, 2013
  • #14
Lol I will remember that , and to everybody I know very little just the things I would check , it was only an idea not a recommendation , I don't know about boosted cars , but an here tryin to learn like everyone else
 
Reactions: MikeH686 and 84Ttop

madspeed

Colonel Mustard
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Nov 29, 1999
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a van down by the river
Sep 29, 2013
#15
  • Sep 29, 2013
  • #15
no smoke, no oil burnng. Just gonna order new gaskets and reinstall. I just wonder how/why oil was getting onto the stud, but i'll guess no big dealio
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
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In the garage
Sep 29, 2013
#16
  • Sep 29, 2013
  • #16
Mad, all I can think of is the bad HG was allowing oil to get sucked up into that valve when it opened under boost. It seeks the path of easiest or least resistence. What's the combustion chamber and pistion look like?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
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PA
Sep 29, 2013
#17
  • Sep 29, 2013
  • #17
mikestang63 said:
Mad, all I can think of is the bad HG was allowing oil to get sucked up into that valve when it opened under boost. It seeks the path of easiest or least resistence. What's the combustion chamber and pistion look like?
Click to expand...

That's what I'm thinking as well


Sent from my XT907 using Tapatalk 2
 
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