mark69sportsroof 31 Report post Posted June 27, 2018 Hi Everyone, I have been reading about all the temperature gauges and issues. My 73 Mach 1 seems to run half to 3/4 gauge hot when driving 40 mph or higher in mid 70's and up. Now I have replace the heater core in the 69 as it started leaking inside the cab. I want to flush and burp both systems. My question is did Ford outline specific instructions on how to properly burp the system? Thanks Mark Quote Share this post Link to post Share on other sites
skidmarky 50 Report post Posted June 27, 2018 Not sure about Fords procedure, but I remove the heater hose from the intake fitting (highest point in the system) and then fill the radiator, this will push the air out as you fill, when coolant comes out the fitting you are good. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted June 27, 2018 One thing that helps prevent trapped air in the cooling system is to have a bleed hole in the thermostat. Some are made with a bleed like the Motorcraft brand. If your thermostat does not have a bleed hole, simply drill one in the stationary part of it. I usually use a 3/32" or 1/8" diameter drill bit. Doing this I have never struggled to bleed air from a cooling system. 1 Caseyrhe reacted to this Quote Share this post Link to post Share on other sites
69volunteer 84 Report post Posted June 27, 2018 Review all the threads about the after market senders. I tried 3 from various suppliers and they all read hot once the car warmed up. I bought a NOS off ebay for reasonable and that solved my problem. Quote Share this post Link to post Share on other sites
jholmes217 65 Report post Posted June 27, 2018 Combine all three previous responses, and you should be good. I like the Robert Shaw thermostats. They have the hole already that 1969_Mach1 mentioned. Quote Share this post Link to post Share on other sites
fvike 173 Report post Posted June 27, 2018 I've always parked the car uphill, removed the radiator cap and let it idle. The radiator is then the highest point and air will escape there. Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted June 27, 2018 Just throw the radiator over your shoulder, and with a thick cloth, tap the back side of the radiator until you hear the burp. Seriously, these old cars are easy to get the air out. Fill the radiator, start the car, fill the radiator if the water goes below the interior panel, and wait until the water starts moving across the top of the radiator, indicating the thermostat has opened. Run the heater, just in case. Fill the radiator to the normal fill level and shut the engine off. Put on radiator cap. You're done. Only the more modern cars have an issue with air pockets above the radiator cap. 2 Caseyrhe and det0326 reacted to this Quote Share this post Link to post Share on other sites
mark69sportsroof 31 Report post Posted June 28, 2018 Thanks for all the great information on the process. Great advice and people at this site. Thanks again. Mark Quote Share this post Link to post Share on other sites
