Hey Everybody, I just installed a throttle body coolent bypass on my 86. Refilled the radiator and ran it in idle to circulate coolent. Radiator and surge tank levels look good, but I am getting a low coolent lite. Could there be more air in the system? I did not have this problem before I started. Any advice would be of great help, thanks.

 

Burp and refill may take a few times.

 

Low level sensor/sender is in the RH radiator tank - have you done something silly to it? You said radiator level appears good. I'd say it's either NOT or you've an issue with the sender/sensor.

 

I suspect you're still fighting air in the engine. Turn the heater on, start it up and wait for the thermostat to open. You should see the coolant in the radiator drop so fill it and put the cap on - you're most likely done. Fill the overflow tank to required level and go out and drive.

I had the same issue till I figured out the easiest way to do it. I took an old antifreeze jug and cut the bottom out. Removed the radiator cap and put it in there. To keep the mess down, I duct taped the two together and started the car. That's when I saw how much lower the coolant got when the thermostat opened. The jug was a perfect funnel. Filled it and capped it while running and that was it.

This is obviously assuming you don't have any coolant leaks. If so you need to take care of that first.

One other thing I've done when I had a car that airlocked and wouldn't bleed. Turn on the heater to max, find a parking ramp with a steep incline and go up it in low with higher rpms. Sometimes it will push the air through too, just keep the overflow tank filled so it draws back into the radiator when it cools off.

 

I have an 88 and did a radiator flush and refill a couple of weeks ago. When I started up I got a low coolant light at first then after running for a few minutes and topping off again it went away. I believe it was just an air bubble that caused it. Have not had any issues since.

 

Simple..

Fit one of these, make sure the radiator is full, then from cold, run the motor up and when the 'low coolant' alarm comes on, flip the lever to burp out all the air into the expansion tank.

http://www.ebay.co.uk/itm/1971-90-Ch...wrAdQ-wvxOY_fg

Run as normal and when its cold again, check the coolant level and top up if need be.

As a basic rule, when I fit a thermostat, I bore a 1/8" hole in its frame if it doesn't already have one to allow air to pass better to the radiator.

 

I'd like to point out that coolant is flowing through the heater core any time the HVAC controls are not in MAX position (C60) or AUTO (C68), when the heater water valve is closed. Setting the heater to max does not make a difference.

 

. Thanks to everyone who replied. As soon as I return next week I will Get back at this and put all this great info to use. Thanks all.