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Compression Test Numbers before head install, questions

  • Thread starter Thread starter conartist
  • Start date Start date Jun 30, 2007

conartist

Member
Dec 4, 2002
77
0
6
Windsor, Ontario, Canada
Jun 30, 2007
#1
  • Jun 30, 2007
  • #1
Did a compression test and got the follwing...

#1 - 125
#2 - 110 (100 sometimes)
#3 - 130
#4 - 130
#5 - 135
#6 - 140
#7 - 140
#8 - 125

Now my question is, I suspect that #2 has a problem, so I put some oil in it and re-did the compression test, no change. This leads me to think its a valve problem.

The motor is going to be getting a new set of aluminum heads next week, so my question is,

Do you think I have a healthy bottom end, given these numbers?

Thnx
 

ShortThrow50

Member
Oct 22, 2006
923
2
16
Pa
Jun 30, 2007
#2
  • Jun 30, 2007
  • #2
conartist said:
Did a compression test and got the follwing...

#1 - 125
#2 - 110 (100 sometimes)
#3 - 130
#4 - 130
#5 - 135
#6 - 140
#7 - 140
#8 - 125

Now my question is, I suspect that #2 has a problem, so I put some oil in it and re-did the compression test, no change. This leads me to think its a valve problem.

The motor is going to be getting a new set of aluminum heads next week, so my question is,

Do you think I have a healthy bottom end, given these numbers?

Thnx
Click to expand...

eh, I think its hard to say. Could most likely be the head. Say, how many miles does the block have bro?
 

conartist

Member
Dec 4, 2002
77
0
6
Windsor, Ontario, Canada
Jun 30, 2007
#3
  • Jun 30, 2007
  • #3
80K
 

thumper460

Founding Member
Jul 24, 2000
3,022
2
56
Orange Park , Fl
Jun 30, 2007
#4
  • Jun 30, 2007
  • #4
The rings are weak with 80K on the engine... as well as the timing chain. If you are really excited on the heads... go ahead and put the heads on... just be aware that you DO need to freshen the engine soon!! cool??

Just me....................................

Thumper
 

conartist

Member
Dec 4, 2002
77
0
6
Windsor, Ontario, Canada
Jun 30, 2007
#5
  • Jun 30, 2007
  • #5
Thanks for the input thumper...appreciate it.

The heads goin on it are TFS TW's, I think I'll do the timing chain while I'm in there. The rings can wait til the winter
 
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