#1  
Old 04-28-2020, 08:58 PM
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Default LEAKING ANTI-FREEZE

I have a 66 GTO 389 tri-power. I took it for a drive today and when I got home I notice antifreeze dripping (pretty fast drips). I did not get under the car and check where the leak is coming from. (tomorrow)
My car sits in the garage all winter because I live in Michigan.
It used to sit in an unheated garage back in the day.

Question:
Does this sound like a bad gasket or is the water pump bad?
If it is the water pump. Where is the anti freeze coming from? Just want to know how a water pump goes bad.

Also why would there be antifreeze on top of the water pump?

Thanks
FB66

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Old 04-28-2020, 09:18 PM
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ZeGermanHam ZeGermanHam is offline
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You will usually find coolant on top of the water pump when the seal at the thermostat housing has gone bad. In any regard, it's most likely just a gasket somewhere, but you'll have to perform a more thorough investigation to figure out what you have going on.

For your edification, water pumps can leak between the housing halves, the inlet & outlet hoses, and around impeller shaft seals.

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  #3  
Old 04-28-2020, 09:26 PM
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thank you for your help

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Old 04-28-2020, 09:33 PM
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If it's toward the front of the engine and dead center it's likely a water pump. Look up from the bottom and you'll see a weep hole, roughly a 1/4 inch hole drilled in the bottom of the pump casting. If it's wet the seal on the shaft is bad.

When a car sits for any length of time, upon starting to drive them again they sometimes start to seep.

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Old 04-28-2020, 09:37 PM
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Sounds like there is likely another cause, but sometimes people also top off the coolant in the radiator when getting their classic cars out for the first time of the season, which sometimes results in purging the excess coolant onto the ground when the engine is hot (unless you have a catch can).

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Old 04-28-2020, 09:39 PM
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That sound better that the timing cover. From what I did see under quick inspection. It was in the middle front of engine.
I will check tomorrow.
Thanks

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Old 04-28-2020, 09:41 PM
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ze.
I did not add any this spring. I had it out a couple of times before. Today it leaked bad.
I feel its the water pump.

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Old 04-29-2020, 09:00 AM
69hardtop 69hardtop is offline
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Go to O’Reillys (or similar parts store that loans tools) and get a coolant system pressure tester. You’ll have your answer in a few minutes

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Old 04-29-2020, 12:10 PM
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I had a pretty substantial leak coming from my timing cover. When I jacked up the car and looked under, I saw that the clamp that holds the lower radiator hose on the water pump went back on at a weird angle. (I had replaced the radiator.)

Fixed that, and problem solved.

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Old 04-29-2020, 01:18 PM
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Is there any coolant in the valley pan? I wonder if the gasket (oring) between the timing cover and the intake manifold could be leaking. I have seen that before.

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Old 05-09-2020, 11:12 PM
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I was adjusting my timing today, and saw that a substantial amount of coolant was leaking out from behind the harmonic balancer at high rpms. Off to borrow a pressure tester.

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