For some reason my car hates heat!

[Fury440]

For the first 90,000 miles of it's life it was happy in the cold and the heat. No AC, 7 blade fan, 22" rad, no shroud and no overflow bottle because it never over heated. The block was boiled, the heads were boiled and the rad was rebuilt with an OEM core. The water pump, thermostat and rad cap are all new. It should be it's old self, but it's not.

Last night I was driving here and there in 30+ C ( about 86F ) and the temp slowly rose to about 230F and steam started to fill the engine compartment. Steam was coming out around the cowl was being sucked up by air vents and coming out of the defroster vents. I assume the steam was coming out the rad cap release. It was exciting!

Back when Cancritter (Derek) unveiled his '71 GT, Dobalovr (Many thanks
Graham) gave me an overflow bottle (application unknown) so today I decided it was time to see if it would fit. It's perfect. Tomorrow I'll do another slow cruise and see what my temp does with a "full" rad.

My next adventure may involve Thermocure if I can find a sujpplier up here in the usually cold but sometimes hot north. Lots of place stock Evapo-Rust but not the flush. Anyone actually tried Thermocure or is it snaked oil? I've used Evapo-Rust and it's a great product so maybe their Thermocure is good to. Comments?

 

[luigi164]

Gonna watch this thread. . . I'm also gonna ad an overflow bottle. . .

 

[commando1]

Well, in this case, it IS the thermostat.

 

[luigi164]

Doubt it...it's new.

 

[300rag]

...
Back when Cancritter (Derek) unveiled his '71 GT, Dobalovr (Many thanks
Graham) gave me an overflow bottle (application unknown) so today I decided it was time to see if it would fit. It's perfect. ...
View attachment 132152 View attachment 132153

...

Can't help you on the thermocure, but that bottle fits in there nicely. It didn't on my wagon due to all the A/C stuff in the way. That bottle is from a mid 80's 1/2 ton, BTW. It's what I put in my 300 10 years ago.
Here is a link to a post from earlier today about Thermocure

My 440 GT boils after I switch the engine off

Gonna watch this thread. . . I'm also gonna ad an overflow bottle. . .

 

[Dobalovr]

I have a spare BTW....

Here's mine before @CanCritter got to the engine compartment

 

[Dobalovr]

For the first 90,000 miles of it's life it was happy in the cold and the heat. No AC, 7 blade fan, 22" rad, no shroud and no overflow bottle because it never over heated. The block was boiled, the heads were boiled and the rad was rebuilt with an OEM core. The water pump, thermostat and rad cap are all new. It should be it's old self, but it's not.

Last night I was driving here and there in 30+ C ( about 86F ) and the temp slowly rose to about 230F and steam started to fill the engine compartment. Steam was coming out around the cowl was being sucked up by air vents and coming out of the defroster vents. I assume the steam was coming out the rad cap release. It was exciting!

Back when Cancritter (Derek) unveiled his '71 GT, Dobalovr (Many thanks
Graham) gave me an overflow bottle (application unknown) so today I decided it was time to see if it would fit. It's perfect. Tomorrow I'll do another slow cruise and see what my temp does with a "full" rad.

View attachment 132152 View attachment 132153

My next adventure may involve Thermocure if I can find a sujpplier up here in the usually cold but sometimes hot north. Lots of place stock Evapo-Rust but not the flush. Anyone actually tried Thermocure or is it snaked oil? I've used Evapo-Rust and it's a great product so maybe their Thermocure is good to. Comments?

Need to make sure the rad cap has the double seal to allow return as well as overflow BTW!

 

[saylor]

i just used the thermocure like yesterday i flushed it after 4 days.

i let my car sit in the driveway in park and it stayed at 209*

 

[300rag]

Need to make sure the rad cap has the double seal to allow return as well as overflow BTW!

The parts counter guy will just give you a deer in the headlights look if he isn't a greybeard. BTDT

 

[tbm3fan]

I don't like heat either so is there an overflow bottle I can use...

 

[300rag]

I don't like heat either so is there an overflow bottle I can use...

 

[CanCritter]

when me and Pete went for drive in GT brought it up to temp...showed 180 on external temp gage...in dash gage showed barely over 1/4

 

[Fury440]

I checked my rad cap, looks like the right kind. I guess I'll find out after a run to see if it sucks back as the system cools.

Well, in this case, it IS the thermostat.

Don't think so, at highway speeds the temperature regulation is just fine. However, slow crawl in traffic is not so good. I'm wondering what the impeller on the "new" water pump looks like and what it's flow rate is at low rpm. I recall a water pump flow rate test done a few years back, very interesting read. The results seem to indicate that Ma Mopar built a very efficient pump and most of the after market stuff was crap. One exception was the Milodon HV 440. May take a good look at that one to see if I can restore my low rpm flow rate.

 

[saforwardlook]

22" radiators with a 440 engine are usually inadequate with higher temperatures. I saw this in the hot weather test data when I was working at the Chelsea Proving Grounds on assignment for 3 months at Chrysler back in the day. They were really cheap with their radiator cores based on the hot weather test data.

So you indicate your radiator was rebuilt with an OEM core. How do you know it really is the same fin density core as the original core? You could order replacement NOS radiators from Chrysler, but I am not aware of being able to order an OEM core itself (although a replacement radiator complete is called a "radiator core" in the parts manuals).

To get decent to good low speed cooling at higher temperatures, you mostly need high frontal surface area, so 22" radiators are not ideal, especially with 440 engines (and 3 row vs 4 row won't help anything if your problem is low speed traffic - you only need to increase the rows if higher speed cruising is borderline). If it were me, I would put a 26" radiator support in your car with a 26" radiator, and your problems will disappear. But in every case, I would always specify a very high fin density core especially if you operate your car in warmer climates like here in California and expect to be able to use your a/c (when you have that option) in slow moving traffic. As said before, the factory was too cheap in what margin they originally provided in hot weather traffic. If you must keep the 22 inch radiator, I would definitely change out the core to a very high fin density core, or your problem will never go away no matter what you do. They are expensive, but your radiator shop should know what you are requesting. Craig makes high density cores but there are other brands as well. Stay clear of cores such as Modine Heavy Duty cores. They may be rugged, but they don't do the job because despite the advertising description, they perform worse even than factory because the fin density is even worse than factory.

Been through this many times. But most people keep looking for another magic bullet in these cases, but usually there isn't one relative to a factory system. In the past, I have had a couple 22" radiator equipped C bodies with 440s, and they never worked in the warm California climate even without a/c. Spend a few more $$ and upgrade the core and/or the width of the radiator/support.

One other option is to provide an electric fan for supplemental low speed cooling, but then your beautiful Fury would not look stock under the hood and the results of these aftermarket upgrades isn't always successful either.

 

[Fury440]

I have a spare BTW....

Here's mine before @CanCritter got to the engine compartment

View attachment 132157 View attachment 132158

Now tell me about your washer bottle, it looks pretty nice, mounted like it's supposed to be there.

 

[Fury440]

22" radiators with a 440 engine are usually inadequate with higher temperatures. I saw this in the hot weather test data when I was working at the Chelsea Proving Grounds on assignment for 3 months at Chrysler back in the day. They were really cheap with their radiator cores based on the hot weather test data.

So you indicate your radiator was rebuilt with an OEM core. How do you know it really is the same fin density core as the original core? You could order replacement NOS radiators from Chrysler, but I am not aware of being able to order an OEM core itself (although a replacement radiator complete is called a "radiator core" in the parts manuals).

To get decent to good low speed cooling at higher temperatures, you mostly need high frontal surface area, so 22" radiators are not ideal, especially with 440 engines (and 3 row vs 4 row won't help anything if your problem is low speed traffic - you only need to increase the rows if higher speed cruising is borderline). If it were me, I would put a 26" radiator support in your car with a 26" radiator, and your problems will disappear. But in every case, I would always specify a very high fin density core especially if you operate your car in warmer climates like here in California and expect to be able to use your a/c (when you have that option) in slow moving traffic. As said before, the factory was too cheap in what margin they originally provided in hot weather traffic. If you must keep the 22 inch radiator, I would definitely change out the core to a very high fin density core, or your problem will never go away no matter what you do. They are expensive, but your radiator shop should know what you are requesting. Craig makes high density cores but there are other brands as well. Stay clear of cores such as Modine Heavy Duty cores. They may be rugged, but they don't do the job because despite the advertising description, they perform worse even than factory because the fin density is even worse than factory.

Been through this many times. But most people keep looking for another magic bullet in these cases, but usually there isn't one relative to a factory system. In the past, I have had a couple 22" radiator equipped C bodies with 440s, and they never worked in the warm California climate even without a/c. Spend a few more $$ and upgrade the core and/or the width of the radiator/support.

One other option is to provide an electric fan for supplemental low speed cooling, but then your beautiful Fury would not look stock under the hood and the results of these aftermarket upgrades isn't always successful either.

Unfortunately, you've nailed what I've suspected, "he said" it was OEM but probably not really. His supplier most likely listed it as "a direct OEM replacement" but in fact the length, width and depth are correct while fin count, flow rate and thermal efficiency are anybody's guess. Switching rad supports is a big deal, the least of which is matching the paint quality. Paul's paint work under the hood is crazy amazing, block sanded, many light coats of color, multiple coats of clear followed by wet sand and buffing. I'm not going to muck about with the rad support. Heck it took me awhile to work up the courage to drill two holes to mount the overflow bottle.

I did notice the other day when the steam started to blow, the temp was 230 and putting it in neutral and bumping thed rpm up to 1,500 dropped the temp down to 210 very quickly. That is why I'm thinking a pump more efficient at low rpm might reduce the problem. I agree with you, the best solution is a 26" rad with very high thermal transfer rates and probably a shroud.

 

[Dobalovr]

Bill I just had my original 22" no AC rad recored by Northland Rad in Red Deer. They used a large tube high efficiency copper core and the thing looks great and weighs about 5lbs more than the old rad. I had no overheating issues but then I havent run it in this heat either.

I have a spare washer bottle BTW it works but doesnt fit they way id like. Let me know if you want it.

 

[CanCritter]

Unfortunately, you've nailed what I've suspected, "he said" it was OEM but probably not really. His supplier most likely listed it as "a direct OEM replacement" but in fact the length, width and depth are correct while fin count, flow rate and thermal efficiency are anybody's guess. Switching rad supports is a big deal, the least of which is matching the paint quality. Paul's paint work under the hood is crazy amazing, block sanded, many light coats of color, multiple coats of clear followed by wet sand and buffing. I'm not going to muck about with the rad support. Heck it took me awhile to work up the courage to drill two holes to mount the overflow bottle.

I did notice the other day when the steam started to blow, the temp was 230 and putting it in neutral and bumping thed rpm up to 1,500 dropped the temp down to 210 very quickly. That is why I'm thinking a pump more efficient at low rpm might reduce the problem. I agree with you, the best solution is a 26" rad with very high thermal transfer rates and probably a shroud.

need a shroud or fan just draws from the side....seen the effects first hand when building my 91 gmc...shrouds make a hugeeeee difference in actually drawing air through rad

 

[saforwardlook]

Unfortunately, you've nailed what I've suspected, "he said" it was OEM but probably not really. His supplier most likely listed it as "a direct OEM replacement" but in fact the length, width and depth are correct while fin count, flow rate and thermal efficiency are anybody's guess. Switching rad supports is a big deal, the least of which is matching the paint quality. Paul's paint work under the hood is crazy amazing, block sanded, many light coats of color, multiple coats of clear followed by wet sand and buffing. I'm not going to muck about with the rad support. Heck it took me awhile to work up the courage to drill two holes to mount the overflow bottle.

I did notice the other day when the steam started to blow, the temp was 230 and putting it in neutral and bumping thed rpm up to 1,500 dropped the temp down to 210 very quickly. That is why I'm thinking a pump more efficient at low rpm might reduce the problem. I agree with you, the best solution is a 26" rad with very high thermal transfer rates and probably a shroud.

If you don't want to use a 26" radiator, then I would recore the 22" with a high efficiency core. Adding a shroud if one is available with a 22" radiator would also help.

 

[FURYGT]

I am going to add my 2 cents here based on my own experience and what I did to ensure that I did not have any overheating problems with an expensive new engine. I am with saforwardlook on this problem. I have a 520" pump gas street/strip engine in one of my '68 Sport Fury's, backed by a 727 and 3.73 rear gears and I have a 22" radiator with stock tanks and a 4 row, narrow fin core. The radiator shop I used contacted the company he gets his cores from and that is what they suggested. I also use a high flow aluminum water pump, a factory 7 blade fan with clutch and a factory correct shroud so that under the hood everything looks stock. I have not had any problems with overheating. I got stuck in a traffic jam once is very hot weather and the temp gauge got to the point where I got a bit nervous but the engine did not overheat.

IMHO, you must add a shroud, should upgrade to a high-flow water pump and should consider upgrading the radiator. Given where you live, this should cure your problems. The cost for the radiator work was around $400 (US) 3 years ago. Good luck.

Bill