1968 300, any way to have engine temp lights AND a gauge?

[Snotty]

I just stumbled upon something in the FSM [Page 24-1] about the Cold idiot light regarding why it's there in the first place: You're supposed to wait until it goes out (about 110 degrees by my recent stovetop test) before you turn on your heater and freeze yourself. How brilliantly simple is that?

Not everyone knows this. I came across some teenaged kids sitting in a van. They had the air blowing on high, but the motor was not running. Knowing them I asked what they were doing. "Waiting for Mom, but man, the AC is not working!" My reply, "It won't work unless the motor is running. Without it on, the AC Compressor is not turning and you'll never get any cold air." "What???? Seriously??"

What is very obvious to those who know can be a complete mystery to people who don't.

 

[commando1]

"What???? Seriously??"

 

[live4theking]

I just stumbled upon something in the FSM [Page 24-1] about the Cold idiot light regarding why it's there in the first place: You're supposed to wait until it goes out (about 110 degrees by my recent stovetop test) before you turn on your heater and freeze yourself. How brilliantly simple is that?

Being in the north in the winter the last thing I want to do is shock my windshield by waiting till the motor is warmed up to turn the defrost on. I know folks that have cracked windshields doing that.

Not everyone knows this. I came across some teenaged kids sitting in a van. They had the air blowing on high, but the motor was not running. Knowing them I asked what they were doing. "Waiting for Mom, but man, the AC is not working!" My reply, "It won't work unless the motor is running. Without it on, the AC Compressor is not turning and you'll never get any cold air." "What???? Seriously??"

What is very obvious to those who know can be a complete mystery to people who don't.

That is about as bad as the gal I work with that couldn't understand why she wasn't getting as much out of a tank of gas when someone had convinced her that she should let her car warm up for 10 minutes in the morning and before going home at the end of the day. It took an amazing amount of effort to explain to her that if the motor is running it's burning fuel. Unbelievable.

 

[WissaMan]

Took the car for 20 minute drive the other day. Water temp gauge never went about 165. Outside air temp was in the high 30's low 40's. What do you think is more likely -- bad thermostat or incorrect gauge reading?

 

[Trace 300 Hurst]

Or maybe the car has a 160 'stat....which would make both the stat and the gauge about right.

Stick a cooking thermo (digital is nice, or a laser/infrared gun) into the top of the rad and see what the that water temp is vs. your gauge.

 

[65sporty]

I would start with changing the thermostat

 

[jct]

Could also be engine timing, when i was running factory timing, the temp was around 210° now that i'm around 15° btdc, i'm at 180°

 

[WissaMan]

The cooking thermo is a good idea, I have one of those. I also think that the fan clutch may be too tight. Shouldn't the fan spin real easy when it's cold then have more grab when it heats up? This one spins fast and loud even when it's icy cold outside.

 

[Trace 300 Hurst]

The cooking thermo is a good idea, I have one of those. I also think that the fan clutch may be too tight. Shouldn't the fan spin real easy when it's cold then have more grab when it heats up ? This one spins fast and loud even when it's icy cold outside.

You might be on to something. My engine has a direct drive, aftermarket aluminum flex fan (that I severely dealt with to make it look OEM-ish) that sounds like a friggin' tornado at all times. It moves massive air, for good reason, as my car has always been a New Mexico, Tex, and now Florida car. With my recent new radiator, 14* timing setting, and a few other upgrades that influenced the temp gauge, I'm at exactly 180* (which is the brand new thermostat's rating) no matter what I do in warm Florida [81 degrees today whilst much of the country is in deep freeze]. So if your fan clutch has locked up, that's a lot of cooling.

Gotta take a temp reading of the rad tank, and then maybe consider a new clutch and/or a 'stat. IMO, even with a locked fan clutch on a cool day, the incoming water temp should follow the 'stat on a fully warmed engine.