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HELP! Just finished HCI install, WEIRD coolant leak. With PIC!

  • Thread starter Thread starter jtfairlane
  • Start date Start date Jun 26, 2007

jtfairlane

New Member
Mar 5, 2006
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0
Jun 26, 2007
#1
  • Jun 26, 2007
  • #1
Hey Everybody,

I just finished the last final detail on my H/C/I install, and was filling up the radiator with new coolant and about to fire the car up when I noticed a coolant leak.

Coolant is leaking from one of the two lower right hand bolts/bolt holes that retain the timing chain cover to the block.

I removed the bolt, added thread sealer to the bolt, reinstalled it, and poured more coolant into the radiator. Bolt/bolt hole is still leaking.

Any thoughts/suggestions? I haven't even fire the car up yet, but apparently coolant is traveling up the lower radiator hose through the water pump etc. and leaking out this bolt/bolt hole.

 

Mustang78

New Member
Feb 8, 2006
486
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0
Aberdeen, WA
Jun 26, 2007
#2
  • Jun 26, 2007
  • #2
very odd place for a leak IMO..did your water pump have that steel plate behind it? what kinda gaskets and which sealer did you use/where?

~Mark~
 

jtfairlane

New Member
Mar 5, 2006
468
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0
Jun 26, 2007
#3
  • Jun 26, 2007
  • #3
The water pump did have the steel plate behind it. I used Fel-Pro gaskets and Permatex Blue RTV on both sides of the water pump gasket and both sides of the timing chain cover gasket.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Jun 26, 2007
#4
  • Jun 26, 2007
  • #4
possible cracked cover....best guess (though painfull for the wait) pull the pump and cover, inspect, regasket, and reinstall
 

ShortThrow50

Member
Oct 22, 2006
923
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Pa
Jun 26, 2007
#5
  • Jun 26, 2007
  • #5
jtfairlane said:
The water pump did have the steel plate behind it. I used Fel-Pro gaskets and Permatex Blue RTV on both sides of the water pump gasket and both sides of the timing chain cover gasket.
Click to expand...

I never use sealant around felpro gaskets. I just completed my tfs H/C/I install about 3 weeks ago. Im trying to remember correctly about where your leak is. The bolts for the water pump do not go through any water channels. I did not use sealant on them. If your leak is indeed around the water pump, I would start pointing fingers at your seal. Take it off, clean all the crap off u put on there and reinstall a new felpro dry. Im thinking maybe u screwed up the gasket by accident. Anothher question, is this a new water pump? I have done several builds in the past and have never sealant over top a quality gasket. Im not knocking you because there are people that do it all the time. Im just pointing my finger at your seal
 
B

Boss 351

Here sthhhhhhhheeeve take a picthh of my man flowe
Jul 13, 2003
2,433
23
48
Canada
Jun 26, 2007
#6
  • Jun 26, 2007
  • #6
the leak may collect around that bolt, but it may be from another place. Clean it all off using an airhose and whatever you need, start engine and look for the leak, get some friends with 20/20 vision to help you out.
 
S

savegoodautonfg

New Member
May 11, 2005
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Jun 26, 2007
#7
  • Jun 26, 2007
  • #7
Good luck brother.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Jun 26, 2007
#8
  • Jun 26, 2007
  • #8
The silicone is just fine on the gasket, so that isn't the problem.

I agree with either cracked timing cover, or from another place.

There is a possiblity that it is coming from the bolt hole. If you didn't, let the thread sealer set for a while. But if it came out as quick as it did before, that may not be the problem.

Clean it up where it is leaking, have a friend get his head up in there while the car is running (carefully of course)...and have a looksy while you fill it up...
 

jtfairlane

New Member
Mar 5, 2006
468
3
0
Jun 26, 2007
#9
  • Jun 26, 2007
  • #9
Boss351 and 5spd GT, you guys were right about the leak possibly being from another place but collecting around that bolt hole.

I traced the leak, eventually, to the gasket between the water pump and the steel backing plate....which I had FORGOT to replace with the water pump off.

As for the RTV on the gaskets, all of the instructions I have, in shop manuals, and in water pump installation literature, etc....always say to use sealant on both sides of water pump gaskets.

I ended up taking off the water pump again, and replace it with a new pump. I used Permatex blue rtv on both sides of the backing plate gasket, and on the gasket between the water pump and timing chain cover, and now my motor is perfectly dry!

Thanks for the suggestions and help. I got my motor all buttoned up back together, and now my car runs like a freaking top.
 
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