- Is there any sign of debris circulating around in the coolant in the new core? Was the block flushed, is the engine all original or has it been rebuilt?
- Is it boiling over or is just the gauge showing hot? Not boiling over check gauge and sensor.
- Overheating at low-speed/idle or at highway speeds?
- Using a clutch fan or solid mounted fan?
- Thermostat is easy to remove and check operation with a thermometer and pan of boiling water. A new t-stat may not be as good quality as an older brass one. Not all t-stats are created equal.. the older ones had a larger passage. A good new one can had under the Moroso brand name.. good material and large passage. There may be other brands. Either a 160 or 185 should work.
- Are upper or lower radiator hoses collapsing? Is there a spring present in the hose?
- Is the water pump good? Remove radiator cap when cold, start up to operating temp.. can you see water flow in the top of the radiator?
- Speaking of radiator cap.. do you have the correct type? Hold the cap up so it's in the same orientation as it would be installed and look at the little disc on the bottom. It shouldn't drop down. If it does it's meant for a cooling system with an overflow tank which our cars didn't come with. (this is harder to explain than it really is) Get the correct type cap.
- If you've got the correct type cap is it good? Look for any small crack in the disc below the rubber seal.
From: Harry Torgeson torg66@xxxxxxxxx [Chrysler300] <Chrysler300-noreply@xxxxxxxxxxxxxxx>
To: Chrysler 300 List <Chrysler300@xxxxxxxxxxxxxxx>
Sent: Sun, Aug 9, 2020 9:56 am
Subject: [Chrysler300] over heating 1964 300 K convert A/C
Hi group I need help on overheating, the radiator was record and at 100 degrees for two days it overheated, could I need a different thermostat, do not know what I have now. Also a new problem, the dash light dimmer does not work and the turn signal indicator also failed which both were just replaced with aftermarket parts, any Idea for a source of reliable parts?