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Weird compression test numbers!

  • Thread starter Thread starter TrueBlue95GT
  • Start date Start date May 17, 2005

TrueBlue95GT

Member
Sep 29, 2003
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Connecticut
May 17, 2005
#1
  • May 17, 2005
  • #1
I did another compression test after I finished installing my TFS twisted wedge cylinder heads and I still get 0 psi in the number 5 cylinder. All the others are around 150psi. I'm wondering if that means the rings are shot on that one cylinder? If so, I might have found a mexican block to start a buildup.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 18, 2005
#2
  • May 18, 2005
  • #2
i would expect some compression even with no rings installed at all! are you sure the pushrods are allowing the valves to close?
 

94-302-vert

Active Member
Aug 16, 2004
1,947
2
36
NE CT
May 18, 2005
#3
  • May 18, 2005
  • #3
I agree. remove the VC (Valve Cover as I recently found out) and rotate the engine 2 full revs by hand to make sure both valves open and close. There are many things that could hold one open.

Are the heads the only thing you installed (ie no cam at the same time)?

Chris
 

TrueBlue95GT

Member
Sep 29, 2003
966
0
16
Connecticut
May 18, 2005
#4
  • May 18, 2005
  • #4
I only installed the heads, but the number 5 cylinder got 0 compression even before I did the heads. When I did the heads, I changed the pushrods, lifters and roller rockers, so the only thing possibly holding a valve open would be the cam.
 
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