Refilling the Cooling System
Thread Starter
Racer
Joined: Feb 2006
Posts: 393
Likes: 1
From: Long Island, New York
Refilling the Cooling System
What is the correct procedure for refilling the cooling system? I assume remove the hose from the thermostat housing and fill’er up there. Is this correct?
Moderator
Joined: Jun 1999
Posts: 7,117
Likes: 51
From: Dove Mountain Arizona
Well you SHOULD be able to fill it from the overflow tank and have all be well but I've never had that great of luck with mine. I always get air bubbles in the system causing the fluid to puke out. I've heard that getting a thermostat with the air hole in it cures the problem though. I just fill the engine from the thermostat housing (after removing the stat). This assures the engine/radiator is full with no air. Then I top it off (1/2 full) at the overflow tank with a warm engine. 
Melting Slicks
Joined: Nov 2002
Posts: 2,460
Likes: 5
From: Wheaton IL
I drilled a tiny hole in the flange on my thermostat and can easily fill the system through the overflow tank. I know many consider this a bubba move but it works and the cooling/warmup of the engine is unaffected. The plus is that I don't have to worry about burping the engine and messing around with Wittek clamps and bonded hoses.
Brian
Brian
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Originally Posted by saopm
What is the correct procedure for refilling the cooling system? I assume remove the hose from the thermostat housing and fill’er up there. Is this correct?
I never saw any need to fill other than through the oflo tank. No hole in the thermostat, no filling through the hose or any of that.
I open the heater and then add coolant until the oflo has about an inch of coolant in the bottom of it. Start the engine and let it run until the coolant drops out of the bottom of the tank. At this time the thermostat should suddenly get hot. You can feel it change with your hand. When this happens, I just slowly continue to fill until it is to the proper level. Keep your face away from the oflo opening in case for some reason it should puke. Can't say as I've ever had any problem. Three mid years and a Shark. All the same. Matter of fact, every car and truck I've ever had I've filled this way.
Pro
Joined: Mar 2005
Posts: 586
Likes: 2
From: Liberty TX
Originally Posted by MikeM
I never saw any need to fill other than through the oflo tank. No hole in the thermostat, no filling through the hose or any of that.
I open the heater and then add coolant until the oflo has about an inch of coolant in the bottom of it. Start the engine and let it run until the coolant drops out of the bottom of the tank. At this time the thermostat should suddenly get hot. You can feel it change with your hand. When this happens, I just slowly continue to fill until it is to the proper level. Keep your face away from the oflo opening in case for some reason it should puke. Can't say as I've ever had any problem. Three mid years and a Shark. All the same. Matter of fact, every car and truck I've ever had I've filled this way.
I open the heater and then add coolant until the oflo has about an inch of coolant in the bottom of it. Start the engine and let it run until the coolant drops out of the bottom of the tank. At this time the thermostat should suddenly get hot. You can feel it change with your hand. When this happens, I just slowly continue to fill until it is to the proper level. Keep your face away from the oflo opening in case for some reason it should puke. Can't say as I've ever had any problem. Three mid years and a Shark. All the same. Matter of fact, every car and truck I've ever had I've filled this way.
Pretty much the same here!
