The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-06-2018, 11:10 PM   #1
C4UC101969
Registered User
 
C4UC101969's Avatar
 
Join Date: Aug 2018
Location: BARRIE, Ontario
Posts: 118
Leaking Coolant Probelm

I have this small issue, when i start my truck after parking it for few days or longer I have this very small puddle of coolant below after I move it and this only happens when it is parked for few days and also only after starting the engine(no puddle while it is parked with engine shut off). Then there are no leaks through out the day as I drive and start it on/off. I do have an original overflow tank that looks pretty old but always has coolant in it on the bottom. Any suggestion what this leak might be?
__________________
1969 'Matte Blackie' Oshawa Built Chevy C10 Stepside 307 three-on-the-tree
C4UC101969 is offline   Reply With Quote
Old 11-06-2018, 11:17 PM   #2
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,722
Re: Leaking Coolant Probelm

Hard to tell without being able to look at it. Try to clean & dry as many suspect places as you can, and look for signs of fresh leakage. Look for where it's dripping from and try to trace it back to the source. Could be as simple as a bad radiator cap (if you get a new one, make sure it's for a sealed system). Take a good look at the weep hole in the water pump -- another likely spot. Good luck and keep us posted.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 11-06-2018, 11:56 PM   #3
71CHEVYSHORTBED402
Senior Member
 
71CHEVYSHORTBED402's Avatar
 
Join Date: Feb 2009
Location: Northern Nevada
Posts: 7,322
Re: Leaking Coolant Probelm

The most likely culprits are the simple ones, be sure your clamps are tight. To me, coolant on the bottom of your overflow tank doesn't indicate anything more than a shortage, because the fluid is probably below the tube.
__________________
Tony
71 Custom Deluxe, SWB, 2WD, 402, A/C. I developed an assembly kit for restoring the (a) truck from the ground up. My build thread, and more on the assembly kit https://67-72chevytrucks.com/vboard/...d.php?t=730025
71CHEVYSHORTBED402 is offline   Reply With Quote
Old 11-07-2018, 09:21 AM   #4
sick472
Registered User
 
sick472's Avatar
 
Join Date: Jul 2015
Location: Sedalia Mo.
Posts: 1,131
Re: Leaking Coolant Probelm

I have not done this, but it sounds like a good idea...try using the spray foot powder by spraying the area around the suspected leak. The "hit and miss" leak will show signs in the dried powder. Certainly pay attention to the area above the leak on the ground and any path the coolant could take above along the engine, frame, radiator, etc.
__________________
He who is without oil shall throw the first rod. Compressions 8.7:1

1972 C10
1976 C10 (parts truck)
1985 K20
sick472 is offline   Reply With Quote
Old 11-07-2018, 10:47 AM   #5
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,731
Re: Leaking Coolant Probelm

Quote:
Originally Posted by 71CHEVYSHORTBED402 View Post
The most likely culprits are the simple ones, be sure your clamps are tight. .
There’s your answer right there.
Come winter and colder temps, wherever a hose is attached to your motor, you should tighten the clamp.
The rubber hose doesn’t contract from the cold as much as the metal from the fitting does.
A lot of times they won’t leak like yours does until you start it. Starting it causes enough pressure from the pump to make it leak a bit until the metal heats enough to reseal it.
geezer#99 is offline   Reply With Quote
Old 11-07-2018, 12:30 PM   #6
tdangle
Registered User
 
tdangle's Avatar
 
Join Date: Mar 2005
Location: Jurupa Valley, Ca
Posts: 1,210
Re: Leaking Coolant Probelm

Start it up in the morning when cold and crawl under with a flashlight. You should be able to discover where the leak is coming from. Years ago I had the same issue with a thermostat housing. Would only leak when cold at first startup in the morning.
__________________
Terry

1970 Custom Camper/C20 , GM Crate 350/7004R, Dana 60, factory AC
tdangle is offline   Reply With Quote
Old 11-07-2018, 01:54 PM   #7
C4UC101969
Registered User
 
C4UC101969's Avatar
 
Join Date: Aug 2018
Location: BARRIE, Ontario
Posts: 118
Re: Leaking Coolant Probelm

Thanks guys, I will check it out next time and I'll report back what it is.....
__________________
1969 'Matte Blackie' Oshawa Built Chevy C10 Stepside 307 three-on-the-tree
C4UC101969 is offline   Reply With Quote
Old 11-07-2018, 03:31 PM   #8
cleszkie
Registered User
 
cleszkie's Avatar
 
Join Date: Feb 2003
Location: Santa Ana, CA
Posts: 2,191
Re: Leaking Coolant Probelm

When a water pump begins to go out it will leak some coolant out of the built-in weep hole in the water pump housing. If tightening your hose clamps doesn't solve your leak problem, check the water pump weep hole.
cleszkie is offline   Reply With Quote
Old 11-08-2018, 09:14 PM   #9
C4UC101969
Registered User
 
C4UC101969's Avatar
 
Join Date: Aug 2018
Location: BARRIE, Ontario
Posts: 118
Re: Leaking Coolant Probelm

Yeah tightening all the hose clamps did the trick, thanks guys.
__________________
1969 'Matte Blackie' Oshawa Built Chevy C10 Stepside 307 three-on-the-tree
C4UC101969 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:52 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com