Radiator Overflow since the engine rebuild. 78 Vette
07-17-2018, 01:01 PM
#41
Burning Brakes
Thread Starter
Stant was the manufacturer for the OEM radiator, gas and other caps for many GM cars including our C3 Corvettes.
They are still in business and you can find the proper caps for your year model on line on their website.
Napa auto parts also sell the Stant line of caps on line and in their stores.
They are still top quality caps.
Just an FYI.
They are still in business and you can find the proper caps for your year model on line on their website.
Napa auto parts also sell the Stant line of caps on line and in their stores.
They are still top quality caps.
Just an FYI.
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OldCarBum (07-17-2018)
07-18-2018, 04:06 PM
#42
Burning Brakes
Thread Starter
Update:
I got a new AC Delco RC27 15 lb radiator cap and installed it yesterday. Radiator was full to the top but had to fill the reservoir to the "cool" mark.
Drove it this afternoon for about 30 minutes with the AC and it got to 200 degrees several times.
When I got home and turned off the engine. The reservoir was filled to the "hot" line. It took 10-15 minutes for the anti-freeze in the reservoir to stop bubbling.
It seems to me that the anti-freeze is boiling? Is that possible with a 50/50 mix?
I got a new AC Delco RC27 15 lb radiator cap and installed it yesterday. Radiator was full to the top but had to fill the reservoir to the "cool" mark.
Drove it this afternoon for about 30 minutes with the AC and it got to 200 degrees several times.
When I got home and turned off the engine. The reservoir was filled to the "hot" line. It took 10-15 minutes for the anti-freeze in the reservoir to stop bubbling.
It seems to me that the anti-freeze is boiling? Is that possible with a 50/50 mix?
07-18-2018, 06:15 PM
#43
Le Mans Master
Member Since: Aug 2017
Location: Cool Northern Michigan
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Let us digress.
You are running 200* with the A/C on, in July, in Texas.
You are no longer loosing coolant.
You have the correct lbs of pressure Rad ap.
Your reservoir tank stays around full.
Pure water boils at 212*. You are below that. You have a coolant mix that raises the boiling point.
Your main concern now is, the bubbling in the overflow reservoir tank.
What is the condition of the rubber hose (overflow line) from the Rad filler neck to the reservoir tank?
The rez tank has a plastic cap. Is there a short section of hose from that cap, down into the rez tank?
Off of the rez tanks plastic cap, is there another rubber hose that goes down towards the ground in the event the rez tank overflows?
What are the conditions of those hoses? Are any of them plugged, cracked, deformed?
You are running 200* with the A/C on, in July, in Texas.
You are no longer loosing coolant.
You have the correct lbs of pressure Rad ap.
Your reservoir tank stays around full.
Pure water boils at 212*. You are below that. You have a coolant mix that raises the boiling point.
Your main concern now is, the bubbling in the overflow reservoir tank.
What is the condition of the rubber hose (overflow line) from the Rad filler neck to the reservoir tank?
The rez tank has a plastic cap. Is there a short section of hose from that cap, down into the rez tank?
Off of the rez tanks plastic cap, is there another rubber hose that goes down towards the ground in the event the rez tank overflows?
What are the conditions of those hoses? Are any of them plugged, cracked, deformed?
07-18-2018, 06:46 PM
#44
Burning Brakes
Thread Starter
Let us digress.
You are running 200* with the A/C on, in July, in Texas.
You are no longer loosing coolant.
You have the correct lbs of pressure Rad ap.
Your reservoir tank stays around full.
Pure water boils at 212*. You are below that. You have a coolant mix that raises the boiling point.
Your main concern now is, the bubbling in the overflow reservoir tank.
What is the condition of the rubber hose (overflow line) from the Rad filler neck to the reservoir tank?
The rez tank has a plastic cap. Is there a short section of hose from that cap, down into the rez tank?
Off of the rez tanks plastic cap, is there another rubber hose that goes down towards the ground in the event the rez tank overflows?
What are the conditions of those hoses? Are any of them plugged, cracked, deformed?
You are running 200* with the A/C on, in July, in Texas.
You are no longer loosing coolant.
You have the correct lbs of pressure Rad ap.
Your reservoir tank stays around full.
Pure water boils at 212*. You are below that. You have a coolant mix that raises the boiling point.
Your main concern now is, the bubbling in the overflow reservoir tank.
What is the condition of the rubber hose (overflow line) from the Rad filler neck to the reservoir tank?
The rez tank has a plastic cap. Is there a short section of hose from that cap, down into the rez tank?
Off of the rez tanks plastic cap, is there another rubber hose that goes down towards the ground in the event the rez tank overflows?
What are the conditions of those hoses? Are any of them plugged, cracked, deformed?
There are no other lines to the rez tank.
I did put a new rez tank cap on the tank that had a gasket in it that will let air in and out but also looks like it will separate liquid from air.
All hoses are in good shape. No plugged, cracked or deformed.
I did have an issue with the thermostat today where it hung for a few seconds at 220 before going back to 160.
07-18-2018, 06:51 PM
#45
Le Mans Master
I did have an issue with the thermostat today where it hung for a few seconds at 220 before going back to 160.
07-18-2018, 06:54 PM
#46
Burning Brakes
Thread Starter
07-18-2018, 06:57 PM
#47
Safety Car
Make sure you have no air in the block. If there's a sensor or plug in the crossover passage at the front of the intake, pull that. If not, pull the heater hose that's attached to the crossover passage off. Fill the radiator with coolant until it runs out the hole you've opened in the crossover passage. Plug the "bleed" hole (or reconnect the hose to it) and top up any more if you can at the radiator.
If it's only bubbling when you shut down, that still points to a bad cap. Are you certain you have a stock (ish) radiator and cap? It's the larger style cap, right? A pic of the neck where the cap fits might help with some debugging here.
EDIT: A pic of the overflow tank would also be somewhat useful.
If it's only bubbling when you shut down, that still points to a bad cap. Are you certain you have a stock (ish) radiator and cap? It's the larger style cap, right? A pic of the neck where the cap fits might help with some debugging here.
EDIT: A pic of the overflow tank would also be somewhat useful.
Last edited by C6_Racer_X; 07-18-2018 at 06:59 PM.
07-18-2018, 06:58 PM
#48
Le Mans Master
What type of water pump is on the car? Certain High Flow water pumps like my STewart aluminum Stage 2 pump requires a thermostat with 2-3 ,1/8 inch holes drilled in the base of the thermostat housing to allow coolant by pass with this type of pump. Also, any thermostat should have 1-2 1/8-1/16th inch holes in the base to allow for AIR pockets to not get trapped at the thermostat when closed.
Last edited by jb78L-82; 07-18-2018 at 06:59 PM.
07-18-2018, 07:01 PM
#49
Burning Brakes
Thread Starter
Make sure you have no air in the block. If there's a sensor or plug in the crossover passage at the front of the intake, pull that. If not, pull the heater hose that's attached to the crossover passage off. Fill the radiator with coolant until it runs out the hole you've opened in the crossover passage. Plug the "bleed" hole (or reconnect the hose to it) and top up any more if you can at the radiator.
If it's only bubbling when you shut down, that still points to a bad cap. Are you certain you have a stock (ish) radiator and cap? It's the larger style cap, right? A pic of the neck where the cap fits might help with some debugging here.
If it's only bubbling when you shut down, that still points to a bad cap. Are you certain you have a stock (ish) radiator and cap? It's the larger style cap, right? A pic of the neck where the cap fits might help with some debugging here.
It just seems like the reservoir is where it is boiling. I guess there could be air getting through the cap to the reservoir.
07-18-2018, 07:04 PM
#50
Burning Brakes
Thread Starter
What type of water pump is on the car? Certain High Flow water pumps like my STewart aluminum Stage 2 pump requires a thermostat with 2-3 ,1/8 inch holes drilled in the base of the thermostat housing to allow coolant by pass with this type of pump. Also, any thermostat should have 1-2 1/8-1/16th inch holes in the base to allow for AIR pockets to not get trapped at the thermostat when closed.
I have had this gurgling since the new rebuild which the only difference is the aluminum heads on the car.
07-18-2018, 07:57 PM
#51
Race Director
Pull the thermostat and drill 1-2 1/8" holes in it.
Purge the system of air as it has been pointed out throughout the thread.
Start the car and watch the water flow through the radiator to insure you have good flow, replace the cap and go for a drive.
The boiling water you see in the reservoir is boiling in the system and spewing into the reservoir tank.
Post pictures and maybe a short video.
Find out the part numbers for your heads, the water pump and the head gaskets your builder used to determine the right parts were used.
OEM fan and clutch?
Did you check the fan clutch?
It could even be a small obstruction dropped into a water jacket during assembly and is blocking the flow.
Purge the system of air as it has been pointed out throughout the thread.
Start the car and watch the water flow through the radiator to insure you have good flow, replace the cap and go for a drive.
The boiling water you see in the reservoir is boiling in the system and spewing into the reservoir tank.
Post pictures and maybe a short video.
Find out the part numbers for your heads, the water pump and the head gaskets your builder used to determine the right parts were used.
OEM fan and clutch?
Did you check the fan clutch?
It could even be a small obstruction dropped into a water jacket during assembly and is blocking the flow.
07-18-2018, 08:54 PM
#52
Burning Brakes
Thread Starter
Pull the thermostat and drill 1-2 1/8" holes in it.
Purge the system of air as it has been pointed out throughout the thread.
Start the car and watch the water flow through the radiator to insure you have good flow, replace the cap and go for a drive.
The boiling water you see in the reservoir is boiling in the system and spewing into the reservoir tank.
Post pictures and maybe a short video.
Find out the part numbers for your heads, the water pump and the head gaskets your builder used to determine the right parts were used.
OEM fan and clutch?
Did you check the fan clutch?
It could even be a small obstruction dropped into a water jacket during assembly and is blocking the flow.
Purge the system of air as it has been pointed out throughout the thread.
Start the car and watch the water flow through the radiator to insure you have good flow, replace the cap and go for a drive.
The boiling water you see in the reservoir is boiling in the system and spewing into the reservoir tank.
Post pictures and maybe a short video.
Find out the part numbers for your heads, the water pump and the head gaskets your builder used to determine the right parts were used.
OEM fan and clutch?
Did you check the fan clutch?
It could even be a small obstruction dropped into a water jacket during assembly and is blocking the flow.