I have been here before with some overheating questions. I have more questions now than answers. I have a 62 544 with a 69 2.0 engine. Engine has all new gaskets, seals and lifters. Standard radiator, which seems to have good flow. and fan. Has two 7 inch electric fans in front of radiator. Has a working 160 thermostat(but has also had a 180 working thermostat) 32/36 weber carb conversion, rebuilt, standard 4 speed with rebuilt rear end with 4.1 gears. Distribution tube has had the ports enlarged. Normal antifreeze mix. Original temp gauge and sensor.

Problem: engine experiences run on/dieseling after shutoff so I assume rich or timing slightly off. However runs very well.

Situation: I drove to go to a show today, 75 miles with long stretches of 7% uphill grade. Outside temp ranged from 75 -85F degrees. (when temps get above 100f here the temp gets close to the high white mark) Cruising at 62mph on relative flat land, I was sitting just above middle on temp gauge. Once I hit the hills the temp got very close to the white high area on the gauge.

So the questions. So how accurate are the gauges, should it run that hot going up hills? Hot much will the richness effect temp? Has been very difficult to dial this car in. Electric fans are pushing correctly but seem to make car run warmer when at idle.Did not use them when running at cruising speed. Drove up without any problems at all.

The temp gauge in my 544 instr. cluster, now installed in my 122 seems to be very accurate. prior to installation I tested it on the kitchen stove using my wife's candy thermometer.
Results; 1st White line is 167f; at 1200, 180f; 2nd White line 212f.
I'm running a B18D engine, stock radiator, 180f thermostat and 6 blade fan and a/c in FL. On the highway, no overheating with a/c on. The temp does creep into the red past the 2nd white line if stuck in traffic with the a/c on. In the future, I will probably look for an additional electric pusher fan to keep temp under control.

Hi I have a similar issue. My car's front end is from about 1960 with a very narrow radiator. Fine until it's above 90 degrees and traffic slows (I turn on the heater fan which brings down the temperature meter a bit but heats up the driver). I had thought about the 160 thermostat but I see from your post that may not be the issue. A flush or rebuild at the local radiator shop may help but I found they are mostly all closed down up my way. I suspect--but don't know--that the newer 544s had larger radiators which could minimize if not solve this issue. Does anyone else know about that? Good luck.

You are right, 544 with B18 engines have a bigger radiator requiring a complete new front and hood. Even with this radiator temperature may rise in slow traffic resulting in addition of a electric fan as a booster.
Michael

Get your ignition system dialed in correctly first.
Right plugs gapped correctly;
Right points gapped correctly;
Good cap, rotor and wires;
Right timing set correctly.

Then get the mixture correct in your fuel system.
I've got no advice for a Weber carb. SU guy here.
A lean mixture will tend to run hot, not a rich mixture.

"Standard radiator, which seems to have good flow"
How do you know it has good flow?
Is it the original 56-year old radiator that's never been opened up to clean?
There may be scale built up in there that is not removed by simple flushing.
I believe an 82 degree C thermostat is correct for that engine.

Yes, it is possible that the gauge could be faulty after 56 years.

If you still have the original 4-blade fan, install that.

I tested the gauge and sender and they working correctly. the 2/3 bar of the gauge is 192f. The plugs are gapped properly. They have a dry tan look to them. I worked on timing (recommended 16btdc) for my B20B engine from a different source. Has max advance of 36bdc at 2500 rpm and dialed in the carb more. I will be driving in about 100f outside temp on the freeway and then some stop and go. This should tell me something.

Get yourself an infrared Lazer thermometer and point it at the head near where the temp sensor is located when the engine is hot. Compare the reading to what your guage reads.
I have a totally stock 65 544 with a 180 deg. thermostat. If I drive fast, slow or idle for a long time, the Guage stays past center but still in the green area and varies very little. After I installed the 180 tstat, I was concerned because previously it ran in the middle or below. I then checked with the Lazer thermometer and it read about 175 around the tstat housing and about 180-185 near the back of the head.
Conclusion, the dash guage reads a bit high but is consistent.
You may find that the pusher fans do more harm than good as they block airflow to the radiator. Also check your spark timing as retarded timing can cause overheating.
Post back and let us know how it goes. Tom