1964 Corvette cooling issues
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Joined: Feb 2023
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From: Mobile, AL
1964 Corvette cooling issues
Vehicle started overheating. Now going by temperature gauge on dash mind you. Cannot keep coolant in it. I did only fill half way in the expansion tank. Let run and gauge just about hitting 240. Upon cool down she spits a lot of coolant out the overflow. I have tried multiple times to fill and found that the upper radiator hose doesn't seem to be having much flow. Drove to get ac charged and actually took the top hose off without any coolant in at all. I tried readjusting the hose to not have so high of an arc but to no avail... Granted the water pump is the original. Should I start with the water pump change?
Drifting
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From: Sacramento, Ca
Vehicle started overheating. Now going by temperature gauge on dash mind you. Cannot keep coolant in it. I did only fill half way in the expansion tank. Let run and gauge just about hitting 240. Upon cool down she spits a lot of coolant out the overflow. I have tried multiple times to fill and found that the upper radiator hose doesn't seem to be having much flow. Drove to get ac charged and actually took the top hose off without any coolant in at all. I tried readjusting the hose to not have so high of an arc but to no avail... Granted the water pump is the original. Should I start with the water pump change?
Ted
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From: Mobile, AL
That tstat is only like 3 months old. I understand they go bad and can be bad from factory. But I've been chasing this for weeks. I finally bought a IR temp reader and its reading 190 at the tstat housing. Lower radiator hose 160ish and upper hose toward tstat 180 and toward radiator 170. So no coolant flowing through top hose. At the point of changing water pump just to rule that out!
Drifting
Joined: Aug 2021
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From: Sacramento, Ca
Certainly possible that the water pump is bad especially since you say it is the original pump. Have you checked to make sure the lower hose isn't collapsing. This has been known to happen.
Ted
Ted
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From: Mobile, AL
I have a new OEM hose for the bottom also. Just going to go all in and change everything - water pump, both hoses, sending unit and tstat.
Drifting
Joined: Nov 2004
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From: Folsom Ca
The sending unit is near the T-stat, so if the T-stat reading ( with IR) is only 190, sender shouldn’t be too much more (240 doesn’t sound right).
only overflows when turned off ( cooling down)? Not when running and approaching 240?
have you replaced the cap?
only overflows when turned off ( cooling down)? Not when running and approaching 240?
have you replaced the cap?
Safety Car
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I agree with post #6. Have the radiator cap checked to see if it holds 13lbs pressure. If your water pump was bad I would think that your IR gun would read hot temps. Remember 1/2 full when cold and if the radiator cap will not hold pressure tho top hose will feel empty and the system will push fluid out instead of holding pressure from expansion.
Try to troubleshoot before you start throwing $$ at it.
Try to troubleshoot before you start throwing $$ at it.
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From: Mobile, AL
So going from the start…. Vehicle overheated driving and blew upper hose off. Towed home and replaced hose. Since then have had issue with overheating. Even with cap off and idle overheat. Put burper system on and still overheat. This is why I’m leaning toward water pump.
Le Mans Master
Joined: Feb 2014
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From: Richardson Texas
If your IR gun is only showing temps below 200*, then it sounds like you're getting circulation. As stated earlier in post #6, get a new 15# radiator cap and try that first. System shouldn't puke at temps below 200*...system is not holding pressure...radiator cap.
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Is thermostat installed right side up. Take it out and heat it to a boil in a pan on the stove. I also drill a 1/16" hole in the thermostat.
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From: Mobile, AL
I agree with post #6. Have the radiator cap checked to see if it holds 13lbs pressure. If your water pump was bad I would think that your IR gun would read hot temps. Remember 1/2 full when cold and if the radiator cap will not hold pressure tho top hose will feel empty and the system will push fluid out instead of holding pressure from expansion.
Try to troubleshoot before you start throwing $$ at it.
Try to troubleshoot before you start throwing $$ at it.
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Good luck.
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So is it safe to say that the eliminator was to address a previous overheating issue?
Water pumps can't pump air, and it really seems as if an air pocket is at least part of your trouble. I'm not sure that I understand the 'burper' system you're referring to as having installed.
Water pumps can't pump air, and it really seems as if an air pocket is at least part of your trouble. I'm not sure that I understand the 'burper' system you're referring to as having installed.
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From: Mobile, AL
So is it safe to say that the eliminator was to address a previous overheating issue?
correct
Water pumps can't pump air, and it really seems as if an air pocket is at least part of your trouble. I'm not sure that I understand the 'burper' system you're referring to as having installed.
correct
Water pumps can't pump air, and it really seems as if an air pocket is at least part of your trouble. I'm not sure that I understand the 'burper' system you're referring to as having installed.