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Coolant Pressure/Overflow Tank

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Old 03-23-10, 09:53 AM
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KY Coolant Pressure/Overflow Tank

Alright, this is hopefully different than what happened to my last car.(Blown coolant seal.)

A few days ago when I was trying to start my car, I had to de-flood it(hold down gas, turn over, let off gas, start). Well, it took a few more tries than normal. Let it sit there for about 5 minutes while it warmed up. As I was driving off, I was sorta harsh on it red line in first and second. Redline a day keeps the doctor away ya know. Well, within a mile my coolant light went on, buzzer, turned car off and pulled into a parking lot. Reservoir full, radiator slightly empty.

I've been through the whole blown coolant seal ordeal. Having to add coolant every so often and the sweet smelling exhaust. This doesn't have any of those symptoms, and hasn't happened since either.

Could it have been a fluke?
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Old 03-23-10, 10:21 AM
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Sounds like the coolant is flowing into the overflow tank but not back into the radiator as it should when the engine cools. Check the small-diameter hose that runs from the radiator neck to the overflow tank. If it has a pinhole leak, that can cause this problem. You may not see any leakage of coolant on that hose since the pinhole would basically be an air leak.
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Old 03-23-10, 10:24 AM
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Originally Posted by Go48 View Post
Sounds like the coolant is flowing into the overflow tank but not back into the radiator as it should when the engine cools. Check the small-diameter hose that runs from the radiator neck to the overflow tank. If it has a pinhole leak, that can cause this problem. You may not see any leakage of coolant on that hose since the pinhole would basically be an air leak.
Great idea. Never thought about that. I did buy a new Radiator cap, 13psi. I'll replace that hose also. I'm contemplating replacing all the hoses on the throttle body also. Haven't done that yet, just the main ones.

Do you by chance know the diameter of that hose? I can always take it off and match it if needed.
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Old 03-23-10, 10:44 AM
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my car is doing the same thing, check your water pump.

my water pump is messed up and leaking/letter air in. Only a very little but when its sitting and cooling it sucks air in rather then letting the system suck it from the overflow.

I did the 'bubble test' and nothing (other then the air thats in the system :P)

Top off your coolant daily as the air can build up enough to stop coolant flow.

You may not see it at first, i didn't. But after scratching my head for nearly a week i saw the slow leak comming form the water pump
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Old 03-23-10, 11:45 AM
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Originally Posted by Fleemer View Post
my car is doing the same thing, check your water pump.

my water pump is messed up and leaking/letter air in. Only a very little but when its sitting and cooling it sucks air in rather then letting the system suck it from the overflow.

I did the 'bubble test' and nothing (other then the air thats in the system :P)

Top off your coolant daily as the air can build up enough to stop coolant flow.

You may not see it at first, i didn't. But after scratching my head for nearly a week i saw the slow leak comming form the water pump
That's what I was wondering about. Hasn't been changed yet I don't think. Car has 47k miles on it, sat forever. I'm surprised I haven't changed it out yet. How long a job is that? 30-40 minutes?
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Old 03-23-10, 02:45 PM
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2nd the water pump... thats what my last one ended up being. well basically if there is a hole anywhere in the cooling system, when the coolant cools, it'll just pull air in instead of the water from the overflow.

mine was a PITA to find, because the water pump wasn't really leaking water, after parking it for 2 days, it left 1 drop on the floor, it had no problem sucking air though
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Old 03-24-10, 11:02 AM
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Originally Posted by j9fd3s View Post
2nd the water pump... thats what my last one ended up being. well basically if there is a hole anywhere in the cooling system, when the coolant cools, it'll just pull air in instead of the water from the overflow.

mine was a PITA to find, because the water pump wasn't really leaking water, after parking it for 2 days, it left 1 drop on the floor, it had no problem sucking air though
Yea, this car had an issue with the top radiator hose already. Kept sucking in air and I had no clue where from. Finally saw the drip. 1 drip. Replaced the hose again. Worked fine right after.

So, today or tomorrow I'll switch out the water pump. Gotta find a place around here with a lifetime warranty on it. Autozone doesn't have it, Advance cant get it til tomorrow.
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