Could use some help with cooling system problem
Safety Car
Joined: Nov 2002
Posts: 4,180
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From: out of nowhere
with the 2 above mentions of the heater fan (squirrel cage). If at some point a mouse got in your car, he could have taken nesting material in there (I have seen this in others ‘Vette’s). As stated, you’ll want to pull the fuse, start the car and see if the noise goes away.
Safety Car
Joined: Nov 2002
Posts: 4,180
Likes: 1,176
From: out of nowhere
You say the heat is blowing? If so, you have not taken the power away from the blower fan. In order to tell if it is the blower fan squealing, you need to either pull it’s fuse, or disconnect it’s power supply.
Thread Starter
Intermediate
Joined: Jul 2025
Posts: 35
Likes: 5
Thread Starter
Intermediate
Joined: Jul 2025
Posts: 35
Likes: 5
Still heat problems
After the pump an thermostat replaced it's still hitting red line. An spewing fron reservoir hose I've also noticed the cap looks like it needs a hose that's inside the reservoir itself
Le Mans Master
Joined: Jan 2001
Posts: 6,713
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Kdavis2271
Did you put the Thermostat in the correct orientation (not upside down?)
I would suggest you stop letting it get so hot and stop it before it creeps up to really hot. No use in doing that.
The hose in the plastic reservoir is required for the cooling system to draw coolant back into the system; so yes, you oughta get one.
Since you state you are new to this you should consider purchasing some tools.... that is if you're going to be keeping this car for a while.
Did you put the Thermostat in the correct orientation (not upside down?)
I would suggest you stop letting it get so hot and stop it before it creeps up to really hot. No use in doing that.
The hose in the plastic reservoir is required for the cooling system to draw coolant back into the system; so yes, you oughta get one.
Since you state you are new to this you should consider purchasing some tools.... that is if you're going to be keeping this car for a while.
Melting Slicks
Joined: Jul 2006
Posts: 2,285
Likes: 487
From: Salmon Arm, BC
What does the inside of your radiator look like? Have you backed up that redline temperature with a thermal gun? If not I'd start there, as sensors... if not matched to the gauge, give false readings.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
Drifting
Joined: Jun 2025
Posts: 1,676
Likes: 584
Seems OP owned this '77 C3 about month or 2; (understandably) probably KNOWS little of its true-complete history.
All corvette water pumps have bearings & seals which Require lubrication.
Antifreeze is designed to provide that Lubrication (as well as boil-freeze protection).
If/when cooling system overheats, it may boil over or push most volume into overflow bottle; which ends up wasted on ground. If, (as smilie suggested above) the siphon tube is broken or dislodged, the coolant system may run dry. If pump runs without lubricant it will likely squeal. And, if pump's bearings & seals are dry and seizing, the pump's fan belt also may squeal.
Suggest OP perform a complete flush And heavy-duty chemical cleaning of entire liquid-containing cooling system. Also, replace water pump, thermostat, radiator cap and any damaged or missing parts of the coolant overflow-recovery system. Refill with a 50-50 mix of quality antifreeze concentrate and distilled water.
All corvette water pumps have bearings & seals which Require lubrication.
Antifreeze is designed to provide that Lubrication (as well as boil-freeze protection).
If/when cooling system overheats, it may boil over or push most volume into overflow bottle; which ends up wasted on ground. If, (as smilie suggested above) the siphon tube is broken or dislodged, the coolant system may run dry. If pump runs without lubricant it will likely squeal. And, if pump's bearings & seals are dry and seizing, the pump's fan belt also may squeal.
Suggest OP perform a complete flush And heavy-duty chemical cleaning of entire liquid-containing cooling system. Also, replace water pump, thermostat, radiator cap and any damaged or missing parts of the coolant overflow-recovery system. Refill with a 50-50 mix of quality antifreeze concentrate and distilled water.
What does the inside of your radiator look like? Have you backed up that redline temperature with a thermal gun? If not I'd start there, as sensors... if not matched to the gauge, give false readings.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
Agreed. And for same line of reasoning; Much earlier (P#5) it was suggested same flush plus HD chem cleaning. Even if a peek inside rad cap neck looks ok; no one can see inside the water jackets (where Lots of sediment builds up and scale is bonded). RE: Oxalic Acid, then Sodium Carbonate.
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Thread Starter
Intermediate
Joined: Jul 2025
Posts: 35
Likes: 5
What does the inside of your radiator look like? Have you backed up that redline temperature with a thermal gun? If not I'd start there, as sensors... if not matched to the gauge, give false readings.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
It also could be the radiator needing a flush or replacement.....after all, if it's original it's close to 50 years old, and you never know what kind of crap has been dumped in there.
I had the core replaced in mine 20 some odd years ago and all my engine cooling problems went away.....something to think about.
Le Mans Master
Joined: Jan 2001
Posts: 6,713
Likes: 1,372
This statement doesn't make much sense at the end. I suspect you're using voice-to-text?.... and I have come to readily accept that, but if we're discussing technical items it would probably be beneficial to type things out.
Drifting
Joined: Jun 2025
Posts: 1,676
Likes: 584
agreed. China knock off dragonspeak?
Le Mans Master
Joined: Jan 2001
Posts: 6,713
Likes: 1,372
Kdavis2271
Don't get me wrong. I think Voice-to-Text is a wonderful innovation, comes in quite handy, and I expect that it will only get better, however when discussing technical items it tends to get discombobulated so just proofread whatever you're sending to ensure it's readable.
Don't get me wrong. I think Voice-to-Text is a wonderful innovation, comes in quite handy, and I expect that it will only get better, however when discussing technical items it tends to get discombobulated so just proofread whatever you're sending to ensure it's readable.
Thread Starter
Intermediate
Joined: Jul 2025
Posts: 35
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Was just trying to make a joke about the other 2 vettes we were looking to purchase when this one fell on my lap ahaha one of them had 2 previous owners other one had like 16 I think the guy said an quite a bit diff in milage but I think the one we officially settled on was still owned by the original owner
Melting Slicks
Joined: Jul 2006
Posts: 2,285
Likes: 487
From: Salmon Arm, BC
Was just trying to make a joke about the other 2 vettes we were looking to purchase when this one fell on my lap ahaha one of them had 2 previous owners other one had like 16 I think the guy said an quite a bit diff in milage but I think the one we officially settled on was still owned by the original owner
Drifting
Joined: Jun 2025
Posts: 1,676
Likes: 584
No matter if a C3 or an OTR truck or a 2015 grocery-getter:
In general, it pays to be proactive about vehicle maintenance.
Otherwise, learning the hard way typically costs much much more in T&E. just sayin' nothin' new
In general, it pays to be proactive about vehicle maintenance.
Otherwise, learning the hard way typically costs much much more in T&E. just sayin' nothin' new