low coolant light 86 coupe
Thread Starter
Intermediate
Joined: Jun 2012
Posts: 25
Likes: 0
low coolant light 86 coupe
Just had my heater core replaced on my 86'. The low coolant light is coming on now, usually when I round a clover leaf or take a sharp corner. I know there is lots of brand new coolant in the rad system, so it is definitely not low on coolant. Is there a sensor or float that may be defective?? And if so how hard of a job is it to replace. Or may there be another issue all together like a vacuum/pressure lock?? Any info would be helpful and greatly appreciated.
Cheers
Mark
Cheers
Mark
Pro
Joined: Sep 2012
Posts: 732
Likes: 72
From: the confused state CT
Make sure all the air is out of the system and that it is full, it sounds like the level is still a little low. Check the radiator level when it cools down to see if the level has dropped any. It may take a couple of drive cycles, getting it up to temp and letting it cool down before all the air has escaped. If that doen't work you may have to put the car on ramps or jack up the corner on the filler side of the radiator to create a high spot for the air to escape. I believe the sensor is located in the radiator a few inches below the filler cap.
Gary
Gary
Burning Brakes
Joined: Jun 2003
Posts: 1,079
Likes: 1
From: Niagara Falls ON
When it is cool check the level of coolant....make sure the car is level. Also, start the car and turn the heat on. The level of the coolant should drop a bit when the car is running. Top it off until it doesn't drop. It should be fine after that.
Team Owner
Joined: Jan 2003
Posts: 20,275
Likes: 236
From: Summerland B.C. Canada
You need to pack the cooling system.
Loosen rad cap
Bring engine up to operating temp so that stat is open, confirm by looking into rad to see moving coolant.
Have someone hold gas pedal to about 2000 rpm
Add coolant until full and replace cap
Return to idle rpm and shut motor off, then crack a cold canadian beer.
Loosen rad cap
Bring engine up to operating temp so that stat is open, confirm by looking into rad to see moving coolant.
Have someone hold gas pedal to about 2000 rpm
Add coolant until full and replace cap
Return to idle rpm and shut motor off, then crack a cold canadian beer.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
You need to pack the cooling system.
Loosen rad cap
Bring engine up to operating temp so that stat is open, confirm by looking into rad to see moving coolant.
Have someone hold gas pedal to about 2000 rpm
Add coolant until full and replace cap
Return to idle rpm and shut motor off, then crack a cold canadian beer.
Loosen rad cap
Bring engine up to operating temp so that stat is open, confirm by looking into rad to see moving coolant.
Have someone hold gas pedal to about 2000 rpm
Add coolant until full and replace cap
Return to idle rpm and shut motor off, then crack a cold canadian beer.
Thats how I learned to end the low coolant lite instead of doing the hot/cool down cycles or burping...
I run it up to about 2000...top off with rpm still holding at 2000..place cap back on at 2000...then and only AFTER the system is sealed up tight do I let the rpm come down. Packed like a tin can full of sardines..
The other option is to install a flush valve with a water hose fitting in a heater line. I can flush, pour bottled coolent in the radiator, cap it then connect the hose to pressurize the system and chase out any air thru the loose cap...as liquid starts to escape hit the shut off and the system is 100% liquid with absolutely zero air pockets. This also makes for a good test....I can pressure the system cold with the hose, and leave it stone cold and see how long that pressure will last. usually over night is a good tight system.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
This may be a little late but no one else has mentioned this important step... It helps to jack the front of the car up as high as you can get it, I jack my car up about 16" before packing the system. Corvette's have the radiator set lower then the top of the motor, so jacking the front up helps fill the block first while burping the radiator..Raising the front of the car up on stands will make the procedure easier and guarantee a successful outcome...
...WW
...WW
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