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Losing Coolant

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Old 04-28-2013, 10:34 PM
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Default Losing Coolant

Low coolant level came on the other day and I checked and it was low. Looked for leaks and found nothing. Filled it up and 3 weeks later, low coolant level again. Refilled and checked everywhere for leaks and cannot find any sign of a leak. Checked the oil and it looks ok and the level is correct. I have yet to see any white smoke coming out of tailpipe. Started the truck up today after sitting since Friday night and got some lifter chatter for about 15 seconds. This has never happened... Any ideas? I am thinking maybe a head gasket but praying not.
Old 04-29-2013, 12:20 AM
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Look at the weep hole on the bottom of the water pump and see if it has any pink staining on it or in the area of. If so there is your culprit.
What year is your truck?03-06ish had problems with porous cylinder heads due to a bad casting.
Old 04-29-2013, 07:35 AM
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It is an 03 and I did read somewhere about the casting flaw but have not had time to check. I have replaced the pump once but quite a few miles ago. Just bothering me that the lifters chattering shortly after the coolant was low. Gonna check the oil again this morning before startup and see if any change since I drove it last night. My brother in law borrowed the truck a couple months ago and drive about 200 miles and said it wouldn't hardly run. Went to a dealer and they figured out it a cat cane apart and was blocking the right side. Loosened it up and was able to drive home. I'm thinking the extra back pressure on that side may have blown out the gasket. Just looking for other answers to try first.
Old 04-29-2013, 11:16 AM
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Fill it up cold, and start it while parked on clean concrete. Let it come all the way up to operating temperature. I assume you still have the regular cooling fan on the engine, and that could blow the coolant back on the engine making it harder to locate. More than likely it is the water pump or the water pump gaskets.

Another method would be to pressurize the coolant system when the engine isnt running. If you have access to a comressor, an old overflow tank cap, and can keep the pressure steady and low, it would be pretty easy to find.

Do you have any bubbles blowing into the coolant system? That would be a good indication you have a bad head gasket between the cylinder and coolant.
Old 04-29-2013, 11:35 AM
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Mine does the same thing now.. The steam vents on the heads leak just a lil. enough that the low coolant level comes on ever couple months, i just keep a gallon of water in the tool box
Old 04-29-2013, 12:13 PM
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Originally Posted by 01WS6/tamu
Look at the weep hole on the bottom of the water pump and see if it has any pink staining on it or in the area of. If so there is your culprit.
This was the case on my 01 when I had a similar issue. The water pump slowly went out. I drove it for probably a year without much issue (other than adding coolant every so often) before it finally started to open up and leak more and needed a new pump. It was a slow/small enough leak that it didn't leave any wet spots sitting overnight in the garage in the beginning.
Old 04-30-2013, 08:44 PM
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Got no more time right now so I dropped it off at a shop today. they put pressure on it and no leak. Going to change the oil again and drain into something clear to see if any water in it. Hoping its a water pump cause not to bad to replace and relatively inexpensive. thanks for all the suggestions and will keep posted.
Old 05-01-2013, 06:11 AM
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I have the same problem. I think mine may be a head gaskets because I can see small bubbles in overflow tank when I look down in it. Is a small amount of bubbles normal?
Old 05-01-2013, 10:35 AM
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What casting heads do you have? I would bet almost anything thats going to be your problem.
Old 05-01-2013, 11:38 AM
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welcome to my hell.i have no sign anywhere of leakage, truck runs fine, uses coolant. id say a few hundred miles every time the light comes on.this is after i took the heads off, had them pressure tested, no leaks. they were warped, they were resurfaced. put everything back together with a new gasket set(felpro), and i still have an engine that leaks about half as badly as it did before i tore it down. so, ive just been adding coolant when the low coolant light comes on.ive put about 1500 miles on it since i last changed the oil. ive had to fill it at least 5 times. good luck.


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