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HELP ASAP, Just finished head gasket swap, did compression test,

  • Thread starter Thread starter BlueOvalStangGT
  • Start date Start date Sep 22, 2004
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BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#1
  • Sep 22, 2004
  • #1
Hey guys I just finished swapping my head gaskets(thanks for the help BTW) and I did a compression test in the number 7 and 8 cylinders. I got 120 in #8 and 130 in #7. Is something still wrong? Its better then before but still not as good as my other cylinders. What could be wrong?
 

RIO5.0

15 Year Member
Feb 16, 2001
6,892
8
128
N.H.
Sep 22, 2004
#2
  • Sep 22, 2004
  • #2
That test is supposed to be done with a warm motor...cold, you may not get the seal you need for an accurate reading??

what are the other readings?? w/in 10% of those 2 cyls???

are the valves set-up??? hanging open a tad could skew the numbers???

did you test 7/8 before teardown and they were lower than the others???

bad rings in those cylinders if still low after the install???
 

1105

I AM the random post master...bow down
May 3, 2003
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Daytona Bch, FL
Sep 22, 2004
#3
  • Sep 22, 2004
  • #3
what he said...
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#4
  • Sep 22, 2004
  • #4
OK, before, I dont remember but passenger side was between 135-142 and #8 was 100. #7 was 110 and 5&6 were 125. Now here are the new results

4--142 8--120
3--142 7--130
2--140 6--120
1--140 5--130
 

AznStanger3v

Active Member
Aug 11, 2003
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Northern VA
Sep 22, 2004
#5
  • Sep 22, 2004
  • #5
are you cranking each cylinder the same amount of times?
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#6
  • Sep 22, 2004
  • #6
No I am not, I just crank it until it stops climbing
 
D

DARK-5.0

Founding Member
Feb 20, 2002
724
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Leawood, KS
Sep 22, 2004
#7
  • Sep 22, 2004
  • #7
1105 said:
what he said...
Click to expand...


Comments like this explain to me how your post count is so high. Haha, I'm just playin around Zach. But your right, what he said.

Jeremy
 

1105

I AM the random post master...bow down
May 3, 2003
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Sep 22, 2004
#8
  • Sep 22, 2004
  • #8
DARK-5.0 said:
Comments like this explain to me how your post count is so high. Haha, I'm just playin around Zach. But your right, what he said.

Jeremy
Click to expand...
Comments like this explain to me how YOUR post count it to high too haha not really

He sent me an IM asking me what I thought, so I answered cause he was outside with his car.
 

RacerRick

20+ Year Stangneter
Jun 26, 2004
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Ponchatoula, La.
Sep 22, 2004
#9
  • Sep 22, 2004
  • #9
did you check the head surface and block deck with a straight edge to see if its flat? head could by warped some. since its back together run it a while,heat cycle a few times(hot then cold) then re-torque the head and retest the compresion. good luck!
 

Joes95GT

New Member
Jan 23, 2003
3,132
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0
Delaware
Sep 22, 2004
#10
  • Sep 22, 2004
  • #10
BlueOvalStangGT said:
OK, before, I dont remember but passenger side was between 135-142 and #8 was 100. #7 was 110 and 5&6 were 125. Now here are the new results

4--142 8--120
3--142 7--130
2--140 6--120
1--140 5--130
Click to expand...
It's fine.

Joe
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#11
  • Sep 22, 2004
  • #11
OK NEW PROBLEM! Put all the plugs back in and tryed to start it. It cranks over but makes a funny noise. Its hard to explain but its like a 55gallon drum when you knock on it. It was pretty loud the last time I tried it before I turned it off. Any ideas?
 

Joes95GT

New Member
Jan 23, 2003
3,132
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Sep 22, 2004
#12
  • Sep 22, 2004
  • #12
BlueOvalStangGT said:
OK NEW PROBLEM! Put all the plugs back in and tryed to start it. It cranks over but makes a funny noise. Its hard to explain but its like a 55gallon drum when you knock on it. It was pretty loud the last time I tried it before I turned it off. Any ideas?
Click to expand...
I'm assuming it's coming from the engine? Will the car start and you aren't letting it, or it won't start and makes that noise?

I'd have someone go under the hood (assuming it's from the engine) and try to see exactly where it's coming from. Once you hear where it's coming from, the problem can (probably) be fixed quite easily.

Joe
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#13
  • Sep 22, 2004
  • #13
It wont start and everyone is sleeping around here. Its a really weird kinda "hollow" sound.
 

1105

I AM the random post master...bow down
May 3, 2003
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Daytona Bch, FL
Sep 22, 2004
#14
  • Sep 22, 2004
  • #14
this one has me stumped... I've never heard that kind of noise from any car ever.
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 22, 2004
#15
  • Sep 22, 2004
  • #15
Ok tried again, kept doing it and kept making that sound. Then my mommy came out cause i woke her up so i made her try, and it did it one more time and no it doesnt do it anymore. I only heard it once but I think it may have came from where my airfilter is
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Sep 22, 2004
#16
  • Sep 22, 2004
  • #16
Maybe you have a valve handing open. That would be the only way your air filter or general area would make a sound like that. The air is escaping your cylinders and being forced back up to your intake and out the air inlet. I hope I am dead wrong on that and I seriously doubt that is the problem. Check your spark plugs and make sure they or one of them is not loose.
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Sep 22, 2004
#17
  • Sep 22, 2004
  • #17
BlueOvalStangGT said:
Ok tried again, kept doing it and kept making that sound. Then my mommy came out cause i woke her up so i made her try, and it did it one more time and no it doesnt do it anymore. I only heard it once but I think it may have came from where my airfilter is
Click to expand...

You need to go back and check everything again. Start with the MAF, and go from there. Make sure every injector is in the right spot & make sure every vacuum line is attached. Then, if you still can't start the motor, recheck the rockers & make sure they aren't smacking the valve covers. Also, verify that the cam timing is correct.

Scott
 
D

DARK-5.0

Founding Member
Feb 20, 2002
724
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Leawood, KS
Sep 23, 2004
#18
  • Sep 23, 2004
  • #18
Funny you should have sound like that. I tried starting my car the other night with the dizzy 180 out and of course ir wouldn't start, but i noticed a soft drum noise too. You might as well check that too.

Jeremy
 
D

DARK-5.0

Founding Member
Feb 20, 2002
724
1
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Leawood, KS
Sep 23, 2004
#19
  • Sep 23, 2004
  • #19
1105 said:
Comments like this explain to me how YOUR post count it to high too haha not really

He sent me an IM asking me what I thought, so I answered cause he was outside with his car.
Click to expand...


Hey, just because I don't post in all the thread I read doesn't mean I need to be ridculed as I was. HAHA, just playing. Its all in good fun.

Jeremy
 

BlueOvalStangGT

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Oct 27, 2003
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Sep 23, 2004
#20
  • Sep 23, 2004
  • #20
TTT for me! Heres a sound clip

http://s2.yousendit.com/d.aspx?id=A2B890E375DBFBBFE86FF61B45D03561
 
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