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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Piston Rings Bad? Need Help.

  • Thread starter Thread starter blackstangt
  • Start date Start date Oct 22, 2004

blackstangt

Member
May 31, 2004
460
1
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ny
Oct 22, 2004
#1
  • Oct 22, 2004
  • #1
My car had oil in the upper intake, and it may be coming from the cylinders, if so, do I have bad piston rings, and can i check my plugs to find out?
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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48
Stafford,VA
Oct 22, 2004
#2
  • Oct 22, 2004
  • #2
nope gotta do a compression check......
 

blackstangt

Member
May 31, 2004
460
1
19
ny
Oct 22, 2004
#3
  • Oct 22, 2004
  • #3
what should the compression be, i know it's 9:1 but on the meter...? gt-40 crate motor from ford racing
 

blackstangt

Member
May 31, 2004
460
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19
ny
Oct 22, 2004
#4
  • Oct 22, 2004
  • #4
also will it slowly leak out or do i just get a max
 

IndyBlk5.0

New Member
Nov 24, 2003
1,122
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0
New Whiteland, IN
Oct 22, 2004
#5
  • Oct 22, 2004
  • #5
lol, do some research on piston rings.
90% of the time, oil in your intake is from the pcv sucking oil up from the lower intake and dumping it in the upper. Happens all the time, and there is yet to be a effcient way to fix the problem...
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 22, 2004
#6
  • Oct 22, 2004
  • #6
IndyBlk5.0 said:
lol, do some research on piston rings.
90% of the time, oil in your intake is from the pcv sucking oil up from the lower intake and dumping it in the upper. Happens all the time, and there is yet to be a effcient way to fix the problem...
Click to expand...
hmmm, sounds like pretty much what i said on his other thread. glad im not too far off track.

Blackstang, as i said on your other thread, if it bothers you, a catch can and filter are a good alternative.

i thought you had a fresh block - if so, i would do a compression test (or leakdown test) to see what gives. i might be ticked if my fresh motor burned that much. then again, many new motors do.

was it broken in properly (im getting at having issues with wall glazing)?

good luck.
 

blackstangt

Member
May 31, 2004
460
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19
ny
Oct 23, 2004
#7
  • Oct 23, 2004
  • #7
It's brand new from ford racing, 4500 mi, i didn't more than half gas it for 500 mi. I think it's just from the pcv. thanks for the help guys!
 

IndyBlk5.0

New Member
Nov 24, 2003
1,122
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0
New Whiteland, IN
Oct 23, 2004
#8
  • Oct 23, 2004
  • #8
my car has done 4 dyno runs, many wot pulls, with 530 miles on it. It does not burn one drop of oil, or even a bit of smoke...
 

IndyBlk5.0

New Member
Nov 24, 2003
1,122
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0
New Whiteland, IN
Oct 23, 2004
#9
  • Oct 23, 2004
  • #9
What I'm getting at is, I did my own little thing with my pcv hose. I made it way longer, and it kindof coils behind the motor. The longer the hose it seems, the less oil i get in the intake.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Oct 23, 2004
#10
  • Oct 23, 2004
  • #10
blackstangt said:
It's brand new from ford racing, 4500 mi, i didn't more than half gas it for 500 mi. I think it's just from the pcv. thanks for the help guys!
Click to expand...

A big misconception on breaking in a motor is that your suposed to be real easy on it. Giving it pleny of throttle but keeping the revves down is a better idea, that helps seat the rings.

Do a leakdown check, that will tell you how well your rings and valves are sealing. I did one on my car, failed. I am loosing 50% compression in #6, and over 40% in 4 of the others, and then 30% in 2 and the only one that "passed" was number 3 with 26%. Yes, I have some oil in the intake and I burn some too. About a quart every 700miles.
 

PNY PWR

New Member
Jul 23, 2004
522
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Wichita, KS
Oct 23, 2004
#11
  • Oct 23, 2004
  • #11
I saw a guy with a nitroused Lightning at the track. He has a little glass collector on the pcv line. Looks like an inline water collector for an air compressor. It had alot of oil in it too. He said that oil collecting in the intake causes detonation in those Lightnings. Something like that would help out.


You might have ring/cylinder issues causing exsessive blowby. Probably caused by the poor break procedure used. The motor needs semi-high revs with powered decels to seat those rings good.
 

blackstangt

Member
May 31, 2004
460
1
19
ny
Oct 25, 2004
#12
  • Oct 25, 2004
  • #12
it's just from the pcv, but I'm not too worried as it is a brand new motor, and I've been tuning it and replacing vac hoses and it's been running better and better. As the person who Installed the entire drivetrain, I would expect only something minor like a bad vac line. The oil just scared me a bit, but i'm glad I got so many people who have the same pcv thing going on. Does anyone know why or when it happens, like would it happen if I am going to higher rpm ranges or more if I am going a constant 2200 on the highway for a half hour...?
 
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