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Old 11-06-2018, 11:10 PM   #1
C4UC101969
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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?
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Old 11-06-2018, 11:17 PM   #2
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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.
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Old 11-06-2018, 11:56 PM   #3
71CHEVYSHORTBED402
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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.
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Old 11-07-2018, 09:21 AM   #4
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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.
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Old 11-07-2018, 10:47 AM   #5
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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.
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Old 11-07-2018, 12:30 PM   #6
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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.
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Old 11-07-2018, 01:54 PM   #7
C4UC101969
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Re: Leaking Coolant Probelm

Thanks guys, I will check it out next time and I'll report back what it is.....
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Old 11-07-2018, 03:31 PM   #8
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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.
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Old 11-08-2018, 09:14 PM   #9
C4UC101969
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Re: Leaking Coolant Probelm

Yeah tightening all the hose clamps did the trick, thanks guys.
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