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Engine Coolant leak after replacing water pump

  • Thread starter Thread starter 91GTstroked
  • Start date Start date Sep 9, 2021
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91GTstroked

15 Year Member
Jun 14, 2007
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Sep 9, 2021
#1
  • Sep 9, 2021
  • #1
Hey guys,

I haven't driven my 90 coupe much this year after replacing the timing cover gasket and water pump. Mainly because of what you'll see in the picture.

This picture was after a short drive out of town and in town. But this is as bad as it's been getting. No evidence of it dripping anywhere. It's almost like it's just "sweating" a bit if that makes sense?

Where did I go wrong? I re-tightened everything after a couple heat cycles. Used Permatex thread sealant on the bolt threads. I used Permatex high tack sealant on the gaskets to keep the in place. I put loc-tite on the two bolts on the water pump back plate.

I noticed there was a little slit or groove at the bottom of the timing cover. Was I suppose to put rtv there?

I'll probably keep driving it and checking it so often. It's been sitting for months in my shop with zero coolant leak.

Thanks!
 

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Olivethefet

I will own your nuts! LOL
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Sep 9, 2021
#2
  • Sep 9, 2021
  • #2
Im currently battling a timing chain cover that wont seal properly. I dont really have any advice to help you fix the problem but wanted to point out that you might want to keep an eye on your oil. My leak lets coolant leak into the oil pan and contaminate the oil. Good luck getting it fixed!
 
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91GTstroked

15 Year Member
Jun 14, 2007
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Sep 9, 2021
#3
  • Sep 9, 2021
  • #3
Olivethefet said:
Im currently battling a timing chain cover that wont seal properly. I dont really have any advice to help you fix the problem but wanted to point out that you might want to keep an eye on your oil. My leak lets coolant leak into the oil pan and contaminate the oil. Good luck getting it fixed!
Click to expand...
Thanks I'll keep an eye on it.
 

General karthief

wonder how much it would cost to ship you a pair
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#4
  • Sep 9, 2021
  • #4
The slot at the bottom of the water pump gasket surface looks to me like a drain slot (for what I don't know) and never had the guts to ask, so if anybody knows then spill it.
Yeah, that little leak will be annoying, it may stop over time but I doubt it.
 
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91GTstroked

15 Year Member
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#5
  • Sep 10, 2021
  • #5
General karthief said:
The slot at the bottom of the water pump gasket surface looks to me like a drain slot (for what I don't know) and never had the guts to ask, so if anybody knows then spill it.
Yeah, that little leak will be annoying, it may stop over time but I doubt it.
Click to expand...
Yeah that little leak is annoying. As of now none of it is actually hitting the ground. I would have never known if I hadn't looked under the water pump.
 

General karthief

wonder how much it would cost to ship you a pair
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#6
  • Sep 10, 2021
  • #6
Stop looking
 
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7991LXnSHO

wanna catch the space herp
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Sep 10, 2021
#7
  • Sep 10, 2021
  • #7
For your next gasket change-

Permatex® Form-A-Gasket® No. 2 Sealant

Slow-drying, non-hardening sealant approved for use in aviation as well as automotive applications. Temperature range -65°F to 400°F (-54°C to 204°C); resists gasoline, oil and grease.
www.permatex.com
 

91GTstroked

15 Year Member
Jun 14, 2007
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Sep 10, 2021
#8
  • Sep 10, 2021
  • #8
7991LXnSHO said:
For your next gasket change-

Permatex® Form-A-Gasket® No. 2 Sealant

Slow-drying, non-hardening sealant approved for use in aviation as well as automotive applications. Temperature range -65°F to 400°F (-54°C to 204°C); resists gasoline, oil and grease.
www.permatex.com
Click to expand...
Actually is that a spray that's red? If so, I used that on the water pump gaskets.

The Permatex high tack sealant I used on the cork corner pieces for the oil pan to timing cover.
 

7991LXnSHO

wanna catch the space herp
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#9
  • Sep 10, 2021
  • #9
91GTstroked said:
Actually is that a spray that's red? If so, I used that on the water pump gaskets.

The Permatex high tack sealant I used on the cork corner pieces for the oil pan to timing cover.
Click to expand...
No. This is a different sealer that fils in imperfections. It looks a lot like shellac, but does not harden like that.
 
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Potomus Pete

I'm still waiting for the fully nude shots
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#10
  • Sep 10, 2021
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After I did mine it went away after a while.
 
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nickyb

I gotta say i never painted my nuts, Never Ever
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#11
  • Sep 10, 2021
  • #11
I'll tell you after a few wp changes over the last 14 years I have a (I belive 5/8 open end ) wrench that I ground down to tighten those 2 bolts on backing plate. Once installed I like to make sure they are tight.
 
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General karthief

wonder how much it would cost to ship you a pair
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#12
  • Sep 10, 2021
  • #12
Potomus Pete said:
After I did mine it went away after a while.
Click to expand...
You just ain't checked the coolant in a while, it may have leaked out
 
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jrichker

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#13
  • Sep 10, 2021
  • #13
@Olivethefet

Old cars are like rain; just when you think it has cleared up, it starts again somewhere else...
Look for rust stains after letting this go on for a little while longer. That's a clue as to where to look next

I couldn't get the heater hose connections to stop leaking. I emery clothed the heater tubing coming out of the water pump to clean up it's pitting and roughness and then coated it with blue silicone sealer.

That fixed one leak, but i have another one in the heater hose to the heater core or EGR cooling plumbing. I need to get energized and do the Explorer intake manifold swap that I have been planning.
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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Sep 10, 2021
#14
  • Sep 10, 2021
  • #14
jrichker said:
@Olivethefet

Old cars are like rain; just when you think it has cleared up, it starts again somewhere else...
Look for rust stains after letting this go on for a little while longer. That's a clue as to where to look next

I couldn't get the heater hose connections to stop leaking. I emery clothed the heater tubing coming out of the water pump to clean up it's pitting and roughness and then coated it with blue silicone sealer.

That fixed one leak, but i have another one in the heater hose to the heater core or EGR cooling plumbing. I need to get energized and do the Explorer intake manifold swap that I have been planning.
Click to expand...
you don't need a explorer intake, you need a 471 blower!!
Oh, wait. You gots the Stalker hood nevermind, back to the unscheduled explorer intake install.
 

91GTstroked

15 Year Member
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Sep 11, 2021
#15
  • Sep 11, 2021
  • #15
nickyb said:
I'll tell you after a few wp changes over the last 14 years I have a (I belive 5/8 open end ) wrench that I ground down to tighten those 2 bolts on backing plate. Once installed I like to make sure they are tight.
Click to expand...
That's a good idea. Unfortunately, mine have allen heads. And I tightened them down good and applied loc tire
 

91GTstroked

15 Year Member
Jun 14, 2007
503
281
93
Sep 11, 2021
#16
  • Sep 11, 2021
  • #16
Potomus Pete said:
After I did mine it went away after a while.
Click to expand...
So you had a leak in the same spot?
 

Potomus Pete

I'm still waiting for the fully nude shots
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#17
  • Sep 11, 2021
  • #17
91GTstroked said:
So you had a leak in the same spot?
Click to expand...
No mine was at the top. Very light, but I used some of that ceramic powder sealer a year before. That stuff works incredibly well. It comes in a little jug.
 
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OldManRiver

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Feb 14, 2015
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Sep 11, 2021
#18
  • Sep 11, 2021
  • #18
91GTstroked said:
That's a good idea. Unfortunately, mine have allen heads. And I tightened them down good and applied loc tire
Click to expand...
Button heads right,not socket head cap srews?
I'm sure socket heads were not what was used but must say the height of the heads may cause an interference issue keeping the pump from seating properly.
After all that,if that was the case I'm sure the leak would be more than what your seeing currently.
 

91GTstroked

15 Year Member
Jun 14, 2007
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Sep 12, 2021
#19
  • Sep 12, 2021
  • #19
Water pump seems to be sitting flush.
 
C

chrlsful

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Sep 13, 2021
#20
  • Sep 13, 2021
  • #20
"...if anybody knows then spill it..."
when pump blows U see the signs here ('big gush").

"...Water pump seems to be sitting flush..."
I cant tell from the pic. Did U follow all the recommended proceedures when doing the job? It's not just R&R but rather precise. Inc running the cover on a straight edge to ck for straightness, etc, etc. If U did the FULL job were there any anomalies? How did U solve them?
 
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