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| Running high pressure in cooling system, overheating.; Cooling System | |
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| Tweet Topic Started: Dec 6 2016, 05:07 PM (373 Views) | |
| Jim R Caretaker | Dec 6 2016, 05:07 PM Post #1 |
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Is this thing on...
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So I'm understanding that the cooling system is closed... But I can't keep water in mine. I've done some things. New water pump, thermostat, radiator cap, flushed the system... New head gasket... Runs good, just will not hold water. One visible leak from where the heater hose connects to heater core at the firewall... Inside the engine compartment. And only after pressure builds up in the cooling system. Anyone... Thanks in advance |
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| monzanut | Dec 6 2016, 05:24 PM Post #2 |
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Drip under Pressure
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If possible, you need to do a leak test with one of these...http://geometroforum.com/topic/8039488/1/ , the tester I started topic with. You can pressure the system up and fix any leaks you see. Also look for dampness on passenger floor carpet for heater core leak, sticky fog in the cab when you have heater core leak, smell of sweet antifreeze at the exhaust pipe for internal engine leak into cylinder, chocolate looking oil when leaking into engine. |
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| MarkyMayhem | Dec 8 2016, 11:52 AM Post #3 |
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"One visible leak" - fix it! I was just having some over-cooling issues - cracked hose on the back of the throttle body finally blew out. Fixed it, fixed the issue. Yes - overcooling from a cracked hose. You're symptoms sound like a head gasket but.. You did that so... |
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| monzanut | Dec 8 2016, 12:27 PM Post #4 |
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Drip under Pressure
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When you did the head gasket, did you have the head checked for warp? |
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| freegeo | Dec 8 2016, 12:35 PM Post #5 |
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What was done when the head gasket was replaced? The head and block surfaces checked for flatness? Any known visible leaks need to be taken care of. Then see if the engine still loses coolant.
You are not just running water in the cooling system right? You mean a coolant mixture instead? |
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| Jim R Caretaker | Dec 8 2016, 01:39 PM Post #6 |
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Is this thing on...
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Yeah 50/50 |
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| Dystopiate666 | Dec 8 2016, 08:35 PM Post #7 |
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Tree Banger
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Pressurized cooling system means you have a compression leak into the cooling system, it really can't come from anywhere else. Best case scenario, you get to do the head gasket again. |
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| freegeo | Dec 8 2016, 10:08 PM Post #8 |
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The cooling system is pressurized. |
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| myredvert | Dec 8 2016, 10:30 PM Post #9 |
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myredvert
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Not necessarily. It depends on exactly how pressurized the system is getting. The cooling system is designed to normally pressurize itself as the coolant temperature increases up to the 13 psi cap rating in order to increase the boiling point comfortably above the normal system operating temperature. The boiling point will increase by a little under 3F for every psi of pressure, so a 50/50 coolant:water mixture with a 0 psi boiling point of roughly 226F will not boil until roughly 259f under 12 psi pressure. After correcting the already identified heater hose coolant leak, measuring the system pressure, observing the coolant flow with the cap off as the coolant heats up and the thermostat opens and watching for bubbles, or performing pressure testing the system can help identify and locate an abnormal pressure source and/or internal or external system leaks. |
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| Dystopiate666 | Dec 9 2016, 05:56 AM Post #10 |
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Tree Banger
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Perhaps I should have said excessive pressure. When my head gasket went, I was springing leaks around the water pump, we won't know until he fixes visible leaks. If symptoms persist with no visible leaks.... |
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| myredvert | Dec 9 2016, 07:37 AM Post #11 |
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myredvert
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I'm with you. ![]() that's the issue with descriptions that aren't specific - "high pressure" in the system could mean a lot of different things to different people, and without knowing specifically what the pressure is it's hard to picture what may (or may not be) wrong in the system. |
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| Jim R Caretaker | Dec 13 2016, 09:42 PM Post #12 |
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Is this thing on...
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Thanks in advance |
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| 1 user reading this topic (1 Guest and 0 Anonymous) | |
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