Mineallmine
Well-Known Member
I just recently got my 63 Dart finished and on the road for the first time. Working through the usual bugs and minor issues but this one is bugging me.
When I am driving my Dart it overheats. I took it to a car show and as I was driving there it overheated on me. I was going around 50MPH at the time so there should have been plenty of air flow. I have also had it overheat when driving around town stop and go.
Here is what I have done so far to try to locate the issue:
Changed thermostat twice (one in the car was quality new one) with no change. Even took the thermostat out and at the advice of a member on here I cut out the middle and ran it like that to simulate the thermostat open all the time. No change.
Car has a new heater core. Radiator was re-cored by a reputable shop reusing only the original top and bottom tanks. New water pump (gates IIRC). Car had core plugs removed when I got it so I blew out that area as well as I could and installed new core plugs. When engine was out and disassembled for new gaskets and seals and new water pump I blew it out again at that time with compressed air. When engine was run for the first time I flushed the engine for half and hour to get any rust/dirt residue out by removing the heater hoses from the heater core and connecting one to a hose and the other ran out the door for run off. Ran the water as high as I could without over pressuring the cap while the car ran until the water ran clear (about half an hour. Ran longer to get it as clean as I could). Fresh coolant was then added and topped off the following day and confirmed a few days after each day to make sure all air was purged. This was all done before the car was even driven to try to make sure I was doing my due diligence to avoid any issues. This was also before I found my overheating issue.
I have a new rad cap for the car as well, but not installed yet. I doubt that will change anything as the temperature goes up to almost hot before the pressure pushes past the cap.
With the car cool and the center cut out of the thermostat I pulled the rad cap and ran the car. It does look like the coolant is pumping, just cant tell how well it is pumping.
Exhaust flapper moves easily and free and spring works as it should. Timing currently is 10 degrees before top dead center. I have also adjusted the valves according to the service manual. I may readjust again just to be sure.
Car starts and runs great until this happens. I am also working on the heat soak issue but that's totally different.
I have ordered the Flowkooler water pump, but not as a fix for this issue, just for better flow. I would like to resolve this issue before it arrives. Any ideas where I should be looking next?
Any help would be greatly appreciated. I am thinking of draining the entire system and hooking up to the upper rad hose with a hose and disconnect the lower to confirm I am getting good circulation and flow through the engine to ensure there are no blockages. I am running out of ideas. Other than that I can only think of a faulty pump or radiator.
Thanks in advance
When I am driving my Dart it overheats. I took it to a car show and as I was driving there it overheated on me. I was going around 50MPH at the time so there should have been plenty of air flow. I have also had it overheat when driving around town stop and go.
Here is what I have done so far to try to locate the issue:
Changed thermostat twice (one in the car was quality new one) with no change. Even took the thermostat out and at the advice of a member on here I cut out the middle and ran it like that to simulate the thermostat open all the time. No change.
Car has a new heater core. Radiator was re-cored by a reputable shop reusing only the original top and bottom tanks. New water pump (gates IIRC). Car had core plugs removed when I got it so I blew out that area as well as I could and installed new core plugs. When engine was out and disassembled for new gaskets and seals and new water pump I blew it out again at that time with compressed air. When engine was run for the first time I flushed the engine for half and hour to get any rust/dirt residue out by removing the heater hoses from the heater core and connecting one to a hose and the other ran out the door for run off. Ran the water as high as I could without over pressuring the cap while the car ran until the water ran clear (about half an hour. Ran longer to get it as clean as I could). Fresh coolant was then added and topped off the following day and confirmed a few days after each day to make sure all air was purged. This was all done before the car was even driven to try to make sure I was doing my due diligence to avoid any issues. This was also before I found my overheating issue.
I have a new rad cap for the car as well, but not installed yet. I doubt that will change anything as the temperature goes up to almost hot before the pressure pushes past the cap.
With the car cool and the center cut out of the thermostat I pulled the rad cap and ran the car. It does look like the coolant is pumping, just cant tell how well it is pumping.
Exhaust flapper moves easily and free and spring works as it should. Timing currently is 10 degrees before top dead center. I have also adjusted the valves according to the service manual. I may readjust again just to be sure.
Car starts and runs great until this happens. I am also working on the heat soak issue but that's totally different.
I have ordered the Flowkooler water pump, but not as a fix for this issue, just for better flow. I would like to resolve this issue before it arrives. Any ideas where I should be looking next?
Any help would be greatly appreciated. I am thinking of draining the entire system and hooking up to the upper rad hose with a hose and disconnect the lower to confirm I am getting good circulation and flow through the engine to ensure there are no blockages. I am running out of ideas. Other than that I can only think of a faulty pump or radiator.
Thanks in advance
