My car doesn't like hot weather

200 degrees is nothing to worry about. anything above 220 might be a concern. there is a very good reason cooling systems have pressure caps. engines running too cool will build up moisture and that is not a good thing. I will take an engine running at 210 degrees all day long then one running at 160. just my opinion
 
The 200 degrees is normal to me. Both my F100 and Park Lane specify 195 degree thermostats. After I rebuilt the engine in the F100 I early on had heating issues with the engine during break in and afterwards just running at high idle of 1000 rpm. Large radiator, with correct 5 blade fixed fan and shroud. Part of it was the coolant leak into the engine, pegging the temp gauge, from somewhere which took a year to deal with. The other had to do with using the trucks own gauge which lead to an aftermarket gauge. Turned out the aftermarket gauge is not that accurate. In fact it was 19 degrees off the whole time.

So I got smart and stuck a thermometer in the radiator opening and watched the temperatures. At idle of 750 rpm the temp eventually reaches 204 degrees while the aftermarket gauge says 223 degrees and the OEM gauge isn't quite half way. I am comfortable with 204 as the 390 tends to run a little hot. For piece of mind, given all that I went through with that engine, whenever I run it I double check with a thermometer. It is the only way to know exactly where you stand.
Would the temp be different with the cap on the radiator? I get that you could now make the comparison to your gauges as far as accuracy.
 
Would the temp be different with the cap on the radiator? I get that you could now make the comparison to your gauges as far as accuracy.

I use a 7 lb. cap and having having checked the thermometer against the gauges several times to get a good grasp I can see that the temperature, with the cap on, remains essentially the same between 200-210 degrees.
 
I can see from your first photo that your "Glen Ray" radiator (for whatever that name is worth) has poor fin density, worse than a stock Chrysler radiator core. I am surprised that if your car came from the factory without a/c, that you have a 26" radiator, as usually they were 22" even with the 440. Nevertheless, you need a much higher fin density to adequately cool your engine. They are expensive, as a 3 row high efficiency core will cost near $500 when you are done getting your radiator properly modified. But still cheaper than an engine rebuild. Nothing else solves my idle and low speed creep up in temperature with my 440, especially with the a/c on in hot weather. And in my experience, Chrysler back in those days didn't design in any real margin in the cooling systems once the temperatures exceeded 90F. I drove GM products in that timeframe here in California, and they stayed cool over 100F and their air conditioning effectiveness in the cabin was far better than any of my Chrysler products.
 
When I started towing Connie with the Admiral I swapped for a 7 blade fixed fan. Usually they are noisier but I didn't notice much difference. They will effect fuel mileage, but in a minimal way. NO issues with overheating, even towing in the mountains with the A/C on.

My problems are usually only in low speed traffic above 90F outside. Once underway at any speed above about 30 mph, the cooling systems are adequate under any speed and load, but not at low speeds. When the industry changed over to the cross flow radiators with more than 26" width, these low speed problems generally went away.
 
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Chrysler back in those days didn't design in any real margin in the cooling systems once the temperatures exceeded 90F. I drove GM products in that timeframe here in California, and they stayed cool over 100F and their air conditioning effectiveness in the cabin was far better than any of my Chrysler products.
Since you're talking about experiences, the best AC of any car "back in the day" that my family had was in the '65 Newport my parents bought new. It cooled better and had better air flow than any other car. Had it four years in Sacramento where the summer temps are often above 100*. Never had an overheat and never turned it off. That included a trip to Louisiana and back in '67.
 
Since you're talking about experiences, the best AC of any car "back in the day" that my family had was in the '65 Newport my parents bought new. It cooled better and had better air flow than any other car. Had it four years in Sacramento where the summer temps are often above 100*. Never had an overheat and never turned it off. That included a trip to Louisiana and back in '67.

"Back in the day" in Sacramento doesn't prove much with me, as there was no low speed traffic back then in Sacramento.

I did rent a 1970 Chevrolet Impala back in the day when I was in Maryland with a group of 5 friends, and the temperature was right around 100F and 90% humidity - just horrible. I was stunned when the six of us climbed in that car at the airport and within about 5 minutes had us all comfortable - and in traffic too. I have never been in a Chrysler product in that era that ever came close.
 
"Back in the day" in Sacramento doesn't prove much with me, as there was no low speed traffic back then in Sacramento.
There wasn't? So, before I-80 was built going over downtown (Today called Business Loop 80, built before I-80 was built going through North Highlands) and to get from one end to the other one had to drive surface streets, what exactly did my Mom drive in every day to Watt Avenue in the Chrysler? Empty streets? Don't know how long you've been in California, or where you live, but it's clear you don't know Sac history.

Bottom line, your experience with Mopars and mine are different. My folks also had a motorhome built on a '70 Dodge chassis - superb AC!
 
I am surprised that if your car came from the factory without a/c, that you have a 26" radiator, as usually they were 22" even with the 440.

The TNT engine used the 18 quart (26") radiator like the A/C and trailer towing package cars did.

67_Chrysler_Features_Options_0025.jpg
 
There wasn't? So, before I-80 was built going over downtown (Today called Business Loop 80, built before I-80 was built going through North Highlands) and to get from one end to the other one had to drive surface streets, what exactly did my Mom drive in every day to Watt Avenue in the Chrysler? Empty streets? Don't know how long you've been in California, or where you live, but it's clear you don't know Sac history.

Bottom line, your experience with Mopars and mine are different. My folks also had a motorhome built on a '70 Dodge chassis - superb AC!

I was up there on many occasions, and there was never any traffic that I experienced anything like the creep and crawl that we get in Southern California for hours at a time. Driving back streets isn't traffic to me, as like I said, just being able to move at about 30 mph doesn't cause problems. I have had a lot of Mopars over time and even though they are in top condition, only a high fin density core will keep temps stable at a max of 210F in stop and go traffic with the a/c on over 90F. And the blower speed even on high isn't anything to brag about either in terms of keeping passengers cool under those conditions. I also saw the Chrysler Chelsea Proving Grounds test data on their cooling systems in the early 70s and they were borderline in terms of keeping a car cool on those hot days in creeping traffic conditions simulated on the grounds. But sales were falling and money was tight and saving on radiator size was a big cost saving measure.
 
I can see from your first photo that your "Glen Ray" radiator (for whatever that name is worth) has poor fin density, worse than a stock Chrysler radiator core. I am surprised that if your car came from the factory without a/c, that you have a 26" radiator, as usually they were 22" even with the 440. Nevertheless, you need a much higher fin density to adequately cool your engine. They are expensive, as a 3 row high efficiency core will cost near $500 when you are done getting your radiator properly modified. But still cheaper than an engine rebuild. Nothing else solves my idle and low speed creep up in temperature with my 440, especially with the a/c on in hot weather. And in my experience, Chrysler back in those days didn't design in any real margin in the cooling systems once the temperatures exceeded 90F. I drove GM products in that timeframe here in California, and they stayed cool over 100F and their air conditioning effectiveness in the cabin was far better than any of my Chrysler products.

Maybe a tad more. This is where I got one for my truck.

Chrysler New Yorker, 1966-69 V8 361/383/426/440 Radiator
 
Maybe a tad more. This is where I got one for my truck.

Chrysler New Yorker, 1966-69 V8 361/383/426/440 Radiator

My total cost out the door is just over $500 as of late last year. Mine is a recore, not a completely new radiator because I want to keep the top tank. And without extra air flow via an auxiliary electric fan or something similar, going to 4 row instead of a 3 row doesn't really help much in low speed traffic, but it might if one were having problems at higher speeds. Generally low speed traffic heating requires more frontal area for cooling, but not so much more depth.

Thanks for the chart, as it is helpful as a comparison for me and lays out the options well. Good work!
 
Well, I just got my car back from my mechanic. He's had it almost a MONTH. Of course he doesn't work on my car all the time while he has it. Anyway, I had a whole list of things for him to attend to, most off them minor issues.
Of course a major issue was the cooling issue and thus this thread.
He does a lot of test driving and he said the temp hit 230 on a 90 degree day while he was in traffic. SO, he's finally convinced there IS an issue with the cooling system....Not so sure he fixed it though; he flushed and flushed they system, replaced the rad cap, the thermostat, the water pump and the hoses. He also said he put more water into the coolant (about 60/40 instead of 50/50). Now that I've got the car back we're into a cool spell for about the next two weeks so it probably won't run hot.

Now, I was reading the cooling section of the 67 Chrysler service manual. They have a chart listing the engine combinations along with the cooling system specs.

Here's what I noticed; with the 440 TNT engine and no A/C the car is supposed to have a 26" rad, a fan shroud and a fixed 4 blade fan. It also says a water pump with 10 blades and a ratio for the water pump pulley. Supposed to be 0.95. I guess this means the H2O pump pulley turns at 95% of crankshaft speed.
A/C cars have the shroud, a 7 blade fan with thermal drive AND a different H2O pump with 6 blade. The ratio is 1.4! I guess this means the water pump (and fan) are turning at 1.4% of crankshaft speed.

This would mean a car idling at 500 rpm would have the pump and fan turning at 750. Does this make sense? If so that's the issue. My parts are mismatched!
 
That was just a number for discussion sake. I usually set the idle up near 700.
Anyway, I drove the car a bit yesterday and today. Like I mentioned, were in a cool spell with it staying in the 60's for the next week or so, The temp went up to 180 and pretty much stayed there.

Otherwise the car is running GREAT!
 
Well, an update. We finally have some HOT weather. It got into the low to mid 90's today and I took the car out to see how she'd act. The car was running great while it was coolish; no issues to speak of.

So today I took a ride of about 10 miles to get everything warmed up and nominal. No traffic or stop lights on that route. Then I returned to town and drove for about 45 minutes trying to get caught by as many red lights as I could. Between traffic lights I drove slowly trying to keep the speed below 30 mph. Granted, there were no traffic jams and there aren't a lot of traffic lights in my town.

Anyway, I couldn't get the temp to go above 215. Is this anything to worry about?? I don't think it justifies spending a lot of money on an electric fan.

There's another issue my car's been having in hot weather for about a year now. When it's hot outside and the engine good and hot (such as driving from traffic light to traffic light) when I step on the gas for a lively acceleration, the car gets up and goes and then suddenly BOGS down big time. At first I thought it was an ignition issue but now I'm leaning toward it being a fuel problem. My mechanic thinks it may be vapor lock.
 
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