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Carbed 88 5.0 Weird Oil Psi???

  • Thread starter Thread starter jk294
  • Start date Start date Jun 20, 2013
J

jk294

New Member
Apr 12, 2009
14
0
2
northern Indiana
Jun 20, 2013
#1
  • Jun 20, 2013
  • #1
when i'm cruising on the freeway the oil pressure gets all cattywampus on me. at throttle the oil psi drops and at off throttle it raises. it's a 10 psi variance between 20 and 30 psi.

when i got off the freeway sitting at idle oil pressure dropped to 11psi. letting out on the clutch to start moving it drops to 4psi.

this is all when the oil is warmed up. now when it's cold it's running alot better.

water temp. while i'm on the freeway is pretty much non existent. if i'm in traffic it gets up to about 150 max. I'm wondering if this is having an effect as well.

also under full throttle i shift a 5500 to 6000 rpm.

any help would be great. after seeing that drop to 4psi, i'm starting to worry about the engine.
 

MFE92

10 Year Member
Aug 25, 2010
1,094
373
124
Phoenix
Jun 20, 2013
#2
  • Jun 20, 2013
  • #2
When this happened to me it was because my block was split. Gave it gas, it loaded the block and opened up the clearances. The oil pressure gauge was acting like a vacuum gauge. And my idle pressure was way down.
 
J

jk294

New Member
Apr 12, 2009
14
0
2
northern Indiana
Jun 20, 2013
#3
  • Jun 20, 2013
  • #3
how would i test for such a thing? oh and what exact do you mean by "split"? i'm guessing it's non repairable, but where was the damage located?
 

MFE92

10 Year Member
Aug 25, 2010
1,094
373
124
Phoenix
Jun 20, 2013
#4
  • Jun 20, 2013
  • #4
Do a search for split block and you'll get all kinds of pics. They crack between a main cap bolt hole and the cam bores, then along the lifter valley. Not sure how to check for it without any disassembly.
 

MikeH686

Mine is only two inches though.
10 Year Member
Oct 11, 2011
2,843
1,753
184
Waldorf, MD
Jun 20, 2013
#5
  • Jun 20, 2013
  • #5
Remove your intake and see ... are you smoking after the engine warms up?
 
J

jk294

New Member
Apr 12, 2009
14
0
2
northern Indiana
Jun 20, 2013
#6
  • Jun 20, 2013
  • #6
it doesn't smoke after warm up. but it does tend to mark it's territory. if i park it for a couple hours after warm up ill have a oil spot just a little larger than a half dollar underneath the rear of the engine.
 

MikeH686

Mine is only two inches though.
10 Year Member
Oct 11, 2011
2,843
1,753
184
Waldorf, MD
Jun 20, 2013
#7
  • Jun 20, 2013
  • #7
That would either be trans seal or rear main seal
 
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