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wtf ??? motor issues

  • Thread starter Thread starter 873Stang
  • Start date Start date Jan 22, 2008

873Stang

New Member
Jun 19, 2006
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riverside
Jan 22, 2008
#1
  • Jan 22, 2008
  • #1
so recently i bent a push rod.........aparently i have a fat oil leak on the oil pan that i didn't know about. but im not getting any compression on number 5 the same cylinder the push rod bent, and that rocker are has really bad scaring on it.
so im guessing the valve bent, what would you say? or i have a hole in the piston.

compression test

1)170 5)0
2)180 6)170
3)170 7)170
4)180 8)170


now the wired thing is that 1, 2, 5, and 8 aren't firing they get spark and the plug sparks but if i get a test light and ground out those cylinders at the cap the idle should change but those four dont. im really confused. and number 8 plug will be brown alittle but the compression is 170 so i dont think the rings are bad?

i also check the power going to the injectors which is good also
 

PUNISHER RACING

Active Member
Aug 27, 2007
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36
FORD CITY, PA.
Jan 23, 2008
#2
  • Jan 23, 2008
  • #2
if you had a hole in the piston you will have oil all over that plug as well as oil smoke coming out the back. I put my money on the valve. Get an air chuck tht screws into spark plug hole they use them to change valve prrings with. Remove your rockers from #5 and screw that hose into the plug hole. Hook your air line up to it and listen if you got a bent valve you'll here it coming up the intake or out the exhaust.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jan 23, 2008
#3
  • Jan 23, 2008
  • #3
If you bent a push rod perhaps a valve made contact with something. If you have no compression now maybe its because it is not sealing.
 
3

347HO

Member
Jan 13, 2008
462
2
16
Seattle
Jan 23, 2008
#4
  • Jan 23, 2008
  • #4
Bent pushrod;
#1 the valve spring went into coil bind
#2 as Punisher stated, you bent a valve due to piston contact.

Check for coil bind first, and if you don't have clearance at full open that COULD be the problem.

Next, remove the valve keepers, retainer and spring as Punisher described for that leak test. But the test would pretty much be moot IMO if you don't have coil bind since you'll have to tear down the engine to the point of correcting your problem.
 

873Stang

New Member
Jun 19, 2006
221
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riverside
Jan 23, 2008
#5
  • Jan 23, 2008
  • #5
k did a leak down test,


cyl 5 80psi


cyl 6 80psi


cyl 7 80psi


cyl 7 100psi









now the raocker arms have bad wear or scaring
and milky oil is going to cyl 5 through the intake its also in the pcv valve

what would you guys say
 

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stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Jan 23, 2008
#6
  • Jan 23, 2008
  • #6
bent valve
 

PUNISHER RACING

Active Member
Aug 27, 2007
1,124
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FORD CITY, PA.
Jan 24, 2008
#7
  • Jan 24, 2008
  • #7
did you use the air chuck method this will tell you what happened and what broke?
 

873Stang

New Member
Jun 19, 2006
221
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riverside
Jan 24, 2008
#8
  • Jan 24, 2008
  • #8
PUNISHER RACING said:
did you use the air chuck method this will tell you what happened and what broke?
Click to expand...


i used a leak down test it seemed like the same concept the hose for the compression test i hooked up to a gauge and air compressor
 

873Stang

New Member
Jun 19, 2006
221
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riverside
Jan 24, 2008
#9
  • Jan 24, 2008
  • #9
btw you hear air through the intake manifold
 

PUNISHER RACING

Active Member
Aug 27, 2007
1,124
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36
FORD CITY, PA.
Jan 24, 2008
#10
  • Jan 24, 2008
  • #10
there you go intake valve bent. are you going to have those heads redone or get diff. ones?
 

873Stang

New Member
Jun 19, 2006
221
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0
riverside
Jan 24, 2008
#11
  • Jan 24, 2008
  • #11
PUNISHER RACING said:
there you go intake valve bent. are you going to have those heads redone or get diff. ones?
Click to expand...

the ****ty thing is i just had them done like 900 miles ago so im not sure yet
 

PUNISHER RACING

Active Member
Aug 27, 2007
1,124
0
36
FORD CITY, PA.
Jan 24, 2008
#12
  • Jan 24, 2008
  • #12
sounds like a valve hung up in the guide then lay a straight edge across the valve stems
 
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