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Engine Cooling System Driving Me Crazy

  • Thread starter Thread starter jcgafford
  • Start date Start date Sep 10, 2012

jcgafford

10 Year Member
Jan 7, 2012
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Adrian, MI
Sep 10, 2012
#1
  • Sep 10, 2012
  • #1
Either it is working right and i am losing my mind or it is the water pump. When your car is up to operating temp is the upper radiator hose under pressure and what would happen if you took the radiator cap off? On mine it is never under pressure and i can take the cap off any time without spilling a drop. I even bought a new cap and used that... same thing. you can run it for hours and it never overheats and never fills the overflow. i did pressure check the cooling system a while back before i got it running and it held pressure fine. someone enlighten me before i rip off this water pump!
 

95Vert383AOD

15 Year Member
Jun 10, 2008
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New Bedford, MA
Sep 10, 2012
#2
  • Sep 10, 2012
  • #2
Do you have a thermostat in there?
 

jcgafford

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Sep 10, 2012
#3
  • Sep 10, 2012
  • #3
95Vert383AOD said:
Do you have a thermostat in there?
Click to expand...
did. 192 degree, the oem t-stat. took it out just to satisfy my curiosity today. it is going back in. either way though it never pressurizes the hose.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
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Sep 10, 2012
#4
  • Sep 10, 2012
  • #4
I personally like the 180 degree. You should be running one.

There aren't any leaks? Is it overheating? Have you checked your fan clutch?
 

jcgafford

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Sep 10, 2012
#5
  • Sep 10, 2012
  • #5
95Vert383AOD said:
I personally like the 180 degree. You should be running one.

There aren't any leaks? Is it overheating? Have you checked your fan clutch?
Click to expand...
no leaks i see, NEVER overheats, fan clutch??? if the fan is turning it should be all working, my fan is turning.
 

jcgafford

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Jan 7, 2012
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Sep 10, 2012
#6
  • Sep 10, 2012
  • #6
it has to be the water pump. i just went out and started my explorer and within 10 seconds with the cap off it wants to shoot coolant everywhere. damn it...
 

95Vert383AOD

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#7
  • Sep 10, 2012
  • #7
maybe but its odd that its not overheating.
 

jcgafford

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Sep 10, 2012
#8
  • Sep 10, 2012
  • #8
i am going to go through the whole thing again this saturday. pressure test system and cap. replace t-stat. and last replace pump. i actually did a block test a few weeks ago because i was worried about a head gasket leak, turned out to be fine. i will just repeat all the others again but i see myself ripping the pump out...
 

95Vert383AOD

15 Year Member
Jun 10, 2008
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Sep 10, 2012
#9
  • Sep 10, 2012
  • #9
well if its pretty old it wouldn't hurt. They are pretty cheap.
 

Dino Dino Bambino

15 Year Member
Jun 13, 2007
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Sep 11, 2012
#10
  • Sep 11, 2012
  • #10
jcgafford said:
On mine it is never under pressure and i can take the cap off any time without spilling a drop. I even bought a new cap and used that... same thing. you can run it for hours and it never overheats and never fills the overflow. i did pressure check the cooling system a while back before i got it running and it held pressure fine. someone enlighten me before i rip off this water pump!
Click to expand...

If your water pump isn't leaking and your engine doesn't overheat, you don't have a problem. At worst maybe your radiator cap isn't holding enough pressure. Even though it's new it might not be the right one for you, especially if you have an aftermarket radiator and the filler neck is slightly taller than on the OEM radiator.
 

jcgafford

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Sep 11, 2012
#11
  • Sep 11, 2012
  • #11
tested both caps last night. they both failed... one was the original, other was a stant and was brand new. bought a new stant cap and will re-install the thermostat and new cap today.
 

jcgafford

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Sep 11, 2012
#12
  • Sep 11, 2012
  • #12
after all that it was the cap. the "new" one failed pressure testing as bad as the old one. new cap and now no problems. guess "new" doesnt mean good.
 

gearheadboy

15 Year Member
Jan 15, 2003
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Sep 11, 2012
#13
  • Sep 11, 2012
  • #13
Been there many times..REALLY sux when you are a one man garage and you waste most of your day losing profit because of a bad NEW part. I question the NEW PART the second my problem isn't fixed.
 

jcgafford

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Nov 19, 2013
#14
  • Nov 19, 2013
  • #14
Turns out it was more than a bad cap. the timing chain cover to water pump gasket was junk. changed that out this past summer and the hose is pressurised. Cooling system runs as it should. fyi that upper hose is supposed to hold pressure. if yours doesn't then there is a problem somewhere.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Nov 19, 2013
#15
  • Nov 19, 2013
  • #15
Did you ever pressure test the system? That should have exposed the leak in the gasket. Glad you had the problem resolved.
 

jcgafford

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Nov 19, 2013
#16
  • Nov 19, 2013
  • #16
Three times. Finally read he directions and did it correctly the third time. pissed coolant out the driver side front of the engine. half a day of work and new water pump bolts and it is finally back to proper working order.
 
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