c3 Crazy Overheating issue!
Pro
Joined: Jun 2016
Posts: 567
Likes: 82
From: Auckland
I agree with not replacing anything until you know what the problem is. No point in spending a lot of cash on parts to find it just need burping or that it's a totally different part.
On a totally different subject, what is the switch on the alternator for?
On a totally different subject, what is the switch on the alternator for?
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Ok, so you took the car to the shop to have the oil changed correct? So what was the engine performing like before you took it there? I'm sorry but I'm not seeing a fully restored engine here, so do you have any history of it? What work did this shop advise you needed done and did you authorise it first? How did you collect the car after this work was done? With two plug leads disconnected it would have been running like a dog.
As others have said and I agree you need to check for coolant flow, first thing I would do is start the engine from cold and feel the top radiator hose or the top of the radiator where the hose connects to it, you should feel this getting warm as the thermostat opens, if it doesn't and the gauge is climbing I would pull the thermostat and check it.
FWIW I have never had to burp my coolant system, at least in my case a 1/16" hole drilled in the thermostat seemed to be sufficient to allow any trapped air to escape to the radiator.
As others have said and I agree you need to check for coolant flow, first thing I would do is start the engine from cold and feel the top radiator hose or the top of the radiator where the hose connects to it, you should feel this getting warm as the thermostat opens, if it doesn't and the gauge is climbing I would pull the thermostat and check it.
FWIW I have never had to burp my coolant system, at least in my case a 1/16" hole drilled in the thermostat seemed to be sufficient to allow any trapped air to escape to the radiator.
Safety Car
Joined: May 2001
Posts: 4,737
Likes: 1,638
From: Fairfax Virginia
I Agree with Haggisbash,
I have never had to burp or had any trouble getting the air out of my small block or even my big block engines. I hear about that issue more with the newer LT1's than the C3 engines.
Does he have a bad temperature sensor? How else could it get that hot that fast? Have the temperatures been verified?
Good Luck, and can you Please tell us what was causing this problem when you get it solved? I am really curious....
I have never had to burp or had any trouble getting the air out of my small block or even my big block engines. I hear about that issue more with the newer LT1's than the C3 engines.
Does he have a bad temperature sensor? How else could it get that hot that fast? Have the temperatures been verified?
Good Luck, and can you Please tell us what was causing this problem when you get it solved? I am really curious....
Thread Starter
Cruising
Joined: Apr 2018
Posts: 10
Likes: 1
From: Toronto Ontario
I did have similar problems in my 1969. Overheating as I found can come from many sources. Timing and mixture as well as airflow can play a big part.
Spend some time reading past posts on overheating. I am not saying your problem is a not a lack of coolant getting through your engine but you might just want to check timing and mixture as well.
Good luck. It can be frustrating but slowly and methodically going through your systems will help you get your answers.
Pete
Spend some time reading past posts on overheating. I am not saying your problem is a not a lack of coolant getting through your engine but you might just want to check timing and mixture as well.
Good luck. It can be frustrating but slowly and methodically going through your systems will help you get your answers.
Pete
The timing chain was replaced with the repair, as well as the carb cleaned and new k&n filter. I’ve got a lot of great suggestions here.
Thread Starter
Cruising
Joined: Apr 2018
Posts: 10
Likes: 1
From: Toronto Ontario
Ok, so you took the car to the shop to have the oil changed correct? So what was the engine performing like before you took it there? I'm sorry but I'm not seeing a fully restored engine here, so do you have any history of it? What work did this shop advise you needed done and did you authorise it first? How did you collect the car after this work was done? With two plug leads disconnected it would have been running like a dog.
As others have said and I agree you need to check for coolant flow, first thing I would do is start the engine from cold and feel the top radiator hose or the top of the radiator where the hose connects to it, you should feel this getting warm as the thermostat opens, if it doesn't and the gauge is climbing I would pull the thermostat and check it.
FWIW I have never had to burp my coolant system, at least in my case a 1/16" hole drilled in the thermostat seemed to be sufficient to allow any trapped air to escape to the radiator.
As others have said and I agree you need to check for coolant flow, first thing I would do is start the engine from cold and feel the top radiator hose or the top of the radiator where the hose connects to it, you should feel this getting warm as the thermostat opens, if it doesn't and the gauge is climbing I would pull the thermostat and check it.
FWIW I have never had to burp my coolant system, at least in my case a 1/16" hole drilled in the thermostat seemed to be sufficient to allow any trapped air to escape to the radiator.
Thread Starter
Cruising
Joined: Apr 2018
Posts: 10
Likes: 1
From: Toronto Ontario
I Agree with Haggisbash,
I have never had to burp or had any trouble getting the air out of my small block or even my big block engines. I hear about that issue more with the newer LT1's than the C3 engines.
Does he have a bad temperature sensor? How else could it get that hot that fast? Have the temperatures been verified?
Good Luck, and can you Please tell us what was causing this problem when you get it solved? I am really curious....
I have never had to burp or had any trouble getting the air out of my small block or even my big block engines. I hear about that issue more with the newer LT1's than the C3 engines.
Does he have a bad temperature sensor? How else could it get that hot that fast? Have the temperatures been verified?
Good Luck, and can you Please tell us what was causing this problem when you get it solved? I am really curious....
Safety Car
Joined: Oct 2007
Posts: 3,729
Likes: 267
From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
new temperature sensor is the wrong unit unless you bought specifically from informed corvette specialist.
nearly every over the counter sending unit is incorrect, go to Wilcox corvette for correct sending unit information.
Gauge virtually never fails, 95 % of the time it is the wrong sending unit, the suppliers give you something kinda close.
hang onto the original if you can.
nearly every over the counter sending unit is incorrect, go to Wilcox corvette for correct sending unit information.
Gauge virtually never fails, 95 % of the time it is the wrong sending unit, the suppliers give you something kinda close.
hang onto the original if you can.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
You MUST remove the thermostat to determine 1) if pump is flowing. If pump is flowing with T-stat removed AND the heating problem goes away, the T-stat was bad. If you have poor coolant flow with the T-stat removed, there is blockage somewhere within the cooling system or within the engine. It is possible for the water pump to be faulty; but that would be due to a blockage in pump casting or some obvious assembly error.
Last edited by 7T1vette; Nov 1, 2018 at 09:30 PM.
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