Do all A bodies have overheating problems?

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Comments inside the quote
bluefish1967 said:
I'm using the Milidon high flow thermostat that was recommended with the Milidon high volume water pump. I believe the thermostat was rated at 185.These are all good.
I agree about moving water too quickly through the radiator,This is not your current problem. This should not become a problem until much higher rpm but the problem was there using the stock water pump and 180 thermostat.And that's the proof. I've considered putting a stock thermostat back in. Don't do it, the stat sets the minimum water temp, and has nothing to do with controlling an overheat issue unless it sticks closed, and yours obviously is not sticking closed.
The lower hose is not collapsing, it has the coiled wire in it and is firm when the engine is running.Very good
I am running electric Accumeter gauges, but have checked the temps with an IR gun. Yesterday, the upper hose was showing 221 degrees, the lower showing 210 after idling for 15 minutes.You need to shoot the metal intake right below the thermostat and on the way back to the heads. Keyword "metal".
Agreed, the open element air cleaner makes it worse.Open, closed, or not there at, all makes no difference. Stuffing 221* air into an already overheating engine is like,suicide, to the engine.
I've owned this car for 14 years, and thought recently that I had finally turned the corner. At this point, I really don't know what to try other than a different style of fan blade now you're thinking....Larry
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Firstly, if the rubber is showing that high a temp, then the coolant is way hotter, cuz the rubber is kindof an insulator.
Secondly; the 11* temperature difference says it all; your rad is just not shedding heat. If this is atta standstill then the fan system is squarely to blame.Assuming the cooling fins are attached to the core-tubes,you need more airflow.
I use this type but the one that accepts the thermostatic clutch.
71 72 73 Charger Cuda Challenger Roadrunner Dart OEM 18" 7 blade cooling fan | eBay
 
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I ran that fan ^ on my car before with the proper spacer and it really sucked some air at all times but also robs quite a bit of HP. I ended up swapping to an 18" clutch fan with shroud and narrow clutch on my repop stock style 3 core 70-2 radiator.
 
I have to agree that it is an airflow volume issue with everything I read.
 
Once it's up to temp and the temp is creeping up when the car is stationary, try bringing the rpms up to 1500-1800 and see if the temps come down. I agree with everyone that says it's an air flow issue. There's nothing wrong with your pump or thermostat. What pulley ratio are you running? Under driven water pump pulleys won't spin the fan as fast.
 
I had same issues with various combos until I switched to a factory 7 blade fan and shroud from an A/C equipped car. I used one the the low profile Hayden Fan clutches for clearance. Problem solved! I think the fan blade you are using is your culprit at this point.
 
Wondered about the thermostat because my newly rebuilt 340 with new 185' thermostat heated badly. I pulled the thermostat and placed it in a pan of water on the stove. I watched carefully, and it was at a full boil untill it opened which was not right. I replaced the thermostat and it has not heated since. If the thermostat is okay I am at a loss to help if other solutions already posted don't work.
Yote
 
Sedanman said:
I ran that fan ^ on my car before with the proper spacer and it really sucked some air at all times but also robs quite a bit of HP. I ended up swapping to an 18" clutch fan with shroud and narrow clutch on my repop stock style 3 core 70-2 radiator.
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Sure they rob power. But how many times can you overheat your engine until it gives up, and then it has no power at all!
OP; Beg borrow or steal one, and prove your issue goes away.
Then get one with a THERMOSTATIC clutch on it. The only time it will rob power is when you are not ramming enough air thru the rad; like at low speed or standing still.The thermostat will regulate when to drive it and when to slip it.
And forget all the hype about how much power they suck, cuz those numbers are always biased, to high rpm and fulltime on; a situation that would never occur in real life. Well I suppose it could, if you were towing 80,000 pounds up hill in first gear,WOT for more than a minute or two.......:)
Just test it and see.

Back to that fan;
I bet it follows the same power to resistance ratio that windspeed does; namely, that power increases as the square of the speed. If that was true and it took 32 hp to drive that direct-drive fan at 6000rpm, then at 3000 it would be 32/2squared or 8 hp. And at 1500 it would be 8/2squared or 2hp, and at750 idle it would be 2/2squared or .5hp. An electric fan can draw more than that,lol.
At 30 mph when that fan is likely to kick into freewheel mode, your engine may be doing in the neighborhood of 1300rpm in Drive,so less than 2hp being gobbled up; just before the stat kicks it into freewheel mode.
After 30mph, or thereabouts. Ram-air thru the rad takes over the cooling duties. So; as the airtemp thru the rad cools off, the thermostat on the clutch starts slipping the fan progressively more and more and eventually the fan freewheels in the airstream; just like those pinwheels in your garden do.
Forget about hp loss; just get the biggest damn fan you can lay your hands on, and install it with a thermostatic clutch, and into a shroud.
I have never met anybody who did that and then complained about how sucked out his car was afterwards.
Shooot, if it wasn't for the roaring going on under the hood,I can't even tell when it's working or when it's loafing.
 
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AJ/FormS said:
Sure they rob power. But how many times can you overheat your engine until it gives up, and then it has no power at all!
OP; Beg borrow or steal one, and prove your issue goes away.
Then get one with a THERMOSTATIC clutch on it. The only time it will rob power is when you are not ramming enough air thru the rad; like at low speed or standing still.The thermostat will regulate when to drive it and when to slip it.
And forget all the hype about how much power they suck, cuz those numbers are always biased, to high rpm and fulltime on; a situation that would never occur in real life. Well I suppose it could, if you were towing 80,000 pounds up hill in first gear,WOT for more than a minute or two.......:)
Just test it and see.

Back to that fan;
I bet it follows the same power to resistance ratio that windspeed does; namely, that power increases as the square of the speed. If that was true and it took 32 hp to drive that direct-drive fan at 6000rpm, then at 3000 it would be 32/2squared or 8 hp. And at 1500 it would be 8/2squared or 2hp, and at750 idle it would be 2/2squared or .5hp. An electric fan can draw more than that,lol.
At 30 mph when that fan is likely to kick into freewheel mode, your engine may be doing in the neighborhood of 1300rpm in Drive,so less than 2hp being gobbled up; just before the stat kicks it into freewheel mode.
After 30mph, or thereabouts. Ram-air thru the rad takes over the cooling duties. So; as the airtemp thru the rad cools off, the thermostat on the clutch starts slipping the fan progressively more and more and eventually the fan freewheels in the airstream; just like those pinwheels in your garden do.
Forget about hp loss; just get the biggest damn fan you can lay your hands on, and install it with a thermostatic clutch, and into a shroud.
I have never met anybody who did that and then complained about how sucked out his car was afterwards.
Shooot, if it wasn't for the roaring going on under the hood,I can't even tell when it's working or when it's loafing.
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Thanks for all of the input!!!

Based on what I've read, and the fact that the upper radiator hose was reading 221 degrees and the lower was 210, it has to be airflow and/or flow through the radiator. So I tried an experiment tonight. I removed the Milidon high volume thermostat and tested it in bowling water with my IR gun. While it was somewhat inconsistent with its' opening temp ( 180 ), I was surprised at how much of an opening it has ( hence, high flow ). So, maybe it is flowing too quickly through the radiator and not giving it time to cool. I never tried the high volume pump with a normal thermostat.
I'm still at the belief that my fan is not correct, but I want to try one thing at a time.
Unfortunately, the parts houses did not have a thermostat, so I won't have it till tomorrow. As with the case of this car, and it's age, the only parts I can usually get off the shelf are oil and sometimes an oil filter...LOL.
So I'm going to try my current combination with a stock 180 thermostat and see what happens. I'm also going to explore different types of fans. I'kk keep you posted. Thanks. Larry
 
I can't believe people still repeat the false wives tale of water circulating to fast to cool..... it's utter bs.... your issue is fan/shroud and possibly radiator
 
bluefish1967 said:
Thanks for all of the input!!!

Based on what I've read, and the fact that the upper radiator hose was reading 221 degrees and the lower was 210, it has to be airflow and/or flow through the radiator. So I tried an experiment tonight. I removed the Milidon high volume thermostat and tested it in bowling water with my IR gun. While it was somewhat inconsistent with its' opening temp ( 180 ), I was surprised at how much of an opening it has ( hence, high flow ). So, maybe it is flowing too quickly through the radiator and not giving it time to cool. I never tried the high volume pump with a normal thermostat.
I'm still at the belief that my fan is not correct, but I want to try one thing at a time.
Unfortunately, the parts houses did not have a thermostat, so I won't have it till tomorrow. As with the case of this car, and it's age, the only parts I can usually get off the shelf are oil and sometimes an oil filter...LOL.
So I'm going to try my current combination with a stock 180 thermostat and see what happens. I'm also going to explore different types of fans. I'kk keep you posted. Thanks. Larry
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I would not change that stat! It sets the minimum operating temperature. The minimum. The minimum. Since at anything over 30 mph, your water temp settles down to the minimum, that stat is working perfectly. And that pump needs that stat to work properly.
The moving thru the block too fast, if it occurs at all,will not occur until higher than 5000 rpm. Since I am not having that kind of trouble at 7000 rpm with the same pump and stat, I see this as a non issue for you. Even if you had 4.30s your rpm in first gear at 30mph would still only be 4400. At idle your engine is turning what?, 800 or less. If anything you would need to speed it up!
You want to experiment?, try this; Get your car warmed up, to where the temp starts escalating, then drizzle a fine mist of water onto the front of the rad. Fine enough to to evaporate on the trip through the fins but not enough volume to drown the engine behind it.The goal is to have the rad evaporate the fine mist. It takes a tremendous amount of heat energy to evaporate water. Flooding the rad will not prove anything.The mist has to be evaporating on the trip thru the fins.
I can almost guarantee you that the temp will begin to drop back to the minimum running temp. Unless your fan cannot even pull that little bit of moist air thru the rad.
Have you ever been in traffic in the rain? What was the temperature doing?

BTW, when testing the stat, it has to be suspended in the liquid with no surface in contact with the pot. Your IR gun will not read the water temp properly. You need a proper liquid-testing thermometer.
 
I see what you are getting at....
When testing the thermostat in water, I was more interested in how large of an opening the high volume t-stat had, as compared to a normal one.
I understand what you are saying about misting the radiator, and driving in the rain.
So I'll put the high flow back in, and concentrate on the fan.
I'm running the stock ( I believe ) pulleys that came with the car when new. Haven't checked ratio's or exact sizes. Thanks....
 
I'm pretty sure the ratios will be fine. Besides there are not a lot to choose from in the stock category.

Like I said; beg borrow or steal one of those gigantic direct drive 7 blades.
Test it to prove the problem.
If that cures it,then you can start looking for something in-between.
Here's the fan with the wrong clutch;
MOPAR 7 Blade Fan & Clutch, # 2863216 Charger, RR, GTX, Bee, Cuda, very nice | eBay
Heres the right clutch
NOS MOPAR 3462182 fan clutch max cooling Cuda Challenger Charger Road Runner GTX | eBay

You don't have to buy these pricey items.
I bought a THERMOSTATIC clutch from the Ford dealer for like 70$Can in about 2002. It was off an early 2000s F150. It works better than any Mopar clutch I have ever had.
The fan you can probably score used somewhere for maybe $20. I think they were oem on A/C teenerDarts. There should be a bazillion of them out there by now.
Hayden - Fan Clutches and Fan Blades
 
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I'm going to throw my 3 cents (due to inflation) in. I have seen too many radiators not getting air to flow through them due to crud(cottonwood trees, etc) blocking the fins. Also, too much paint on the fins. And it doesn't help if you stack coolers. My Old Timer test is: with the car running, hood closed, a dryer sheet should suck itself tight to the grille.
 
More than likely not the case but a possibility , is coolant flow through the radiator itself. I agree with your approach to try one thing at a time. If several things are tried at once you will never know which helped or made it worse , not to mention the possible unnecessary expenditure of funds.
Yote
 
depending on how fan is made,..is it on the right way? seen similer issues on a big truck turned fan around run on fine for years!
 
bruceo2011 said:
I'm going to throw my 3 cents (due to inflation) in. I have seen too many radiators not getting air to flow through them due to crud(cottonwood trees, etc) blocking the fins. Also, too much paint on the fins. And it doesn't help if you stack coolers. My Old Timer test is: with the car running, hood closed, a dryer sheet should suck itself tight to the grille.
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This is a brand new( as of December ) radiator that up until recently has not been used on the road. I have checked it with a shop light, and have lightly sprayed it with a garden hose...nothing appears to be clogged in regards to airflow . It has a light coat of flat black as delivered from U S Radiators.
I've tested both fans ( clutch and direct ) at idle using a long section of newspaper draped across the hood down to the top of the bumper. Both fans will pull the newspaper against the grill, with the fixed fan pulling slightly harder.
The fixed fan has a printed tag on the inside blade showing that side facing the engine. It is not trying to push the air forward.
I believe that neither one of my current fans are correct.
In regards to my earlier post about too much flow through the radiator, let me clarify my comments.
When I was in automotive school 40 years ago (yikes ) to be a line tech at Chrysler , we had a semester on cooling systems. We studied the role of a thermostat, how the temp rating was it's opening point, and the actual operating temperature of a particular vehicle was a product of the overall efficiency of the cooling system as a whole. And the thermostats big role is staying closed in cold weather to help an engine warm up. We also studied the effects of removing a thermostat completely from a system. And how it can create a condition where and engine might overheat because the coolant is not staying in the radiator long enough to actually cool down. There was a lot of discussion on t-stats being a certain size, to create a specific limit to how quickly the water flows through the radiator. Thats why I was questioning my use of a high flow t-stat.
When trying to jog my memory, I believe this was NOT a situation at idle, but more of a problem at speed.

Thanks for the ideas. I'll be looking at more fans. Larry
 
might I add , factory fans, correct t stat, radiator ( correct rad paint) OEM for that application....NO added electric fans......

you mentioned in beginning post it had OEM correct 4 blade fan???? to begin with. those were slant 6 fans.

like AJ Forms said, get that f ixed 7 blade OEM fan, and go from there???
 
You have the evidence..cool when moving but over heating when stopped is airflow.
Your rad should have at least a 45-50 degree temp drop, top tank to bottom tank "delta T"
Fan or Rad! A long shot might be not enough timing at idle so all the fire is in the cylinder heads cooking your coolant
 
AJ/FormS said:
The fire is always in the cylinder heads,lol :), But Ima thinking you mean in the exhaust ports and headers/manifolds.
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Yes the big part of the bang should be when the piston is just heading down exposing the hottest part of the flame to the cylinder wall and it's water..not at its hottest exiting the head and exhaust because of late timing.An easy check is glowing headers at night.
 
There is a pretty good discussion on speedtalk about this very issue, maybe the genius who disagreed with me might want to do a little reading there and educate his self so he won't be so clueless. Education is key my freinds!
 
Guess I have never been called a "genius " before, but thanks for the compliment. I have seen a situation where coolant was circulating too fast to properly cool and fixed the problem myself.
I did not just read or hear about it happening.
Yote
 
Yote said:
Guess I have never been called a "genius " before, but thanks for the compliment. I have seen a situation where coolant was circulating too fast to properly cool and fixed the problem myself.
I did not just read or hear about it happening.
Yote
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You might have fixed it overheating, but not because it circulated to
Yote said:
Guess I have never been called a "genius " before, but thanks for the compliment. I have seen a situation where coolant was circulating too fast to properly cool and fixed the problem myself.
I did not just read or hear about it happening.
Yote
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Let me guess, you put a thermostat back in it and it fixed it? Care to elaborate on your fix, it could be educational for everyone
 
R-RACER 43. The engine in question ,new from factory , heated continually untill I decided to change the thermostat as a first option fix. When I removed the thermostat housing there was NO thermostat. I installed the proper rated thermostat and the engine never heated again. That was all that I did. It is obvious that the coolant was circulating too fast to cool. If coolant leaving the radiator is hot the temperature will only rise through the engine and the process continues. If you can provide a more rational explanation , others and myself would like to hear it. My previous post was not just an old wives tail. Due to the reduced size of the orifice in the thermostat it will naturally reduce the flow even when opened fully.
Yote
 
I realize I am a day late and a dollar short, and that a lot of what I will say has already been covered. It has been my experience that when there is an overheat problem, there is a logical reason for it. If you rebuild an engine but the block did not receive a THOROUGH cleaning on the inside, you will have 40-50 years worth of crud keeping the coolant from flowing properly. Double the power output, and you have to do something about the cooling system. The Hood to Radiator to cowl seal was not there for looks. It really did help force air through the radiator. The fan shroud was there for a reason too. It also helped to force air to be sucked through the radiator. If you have a gap between the top of radiator shroud and the radiator, the fan will suck air through that instead of across the radiator. These are just a few ideas off the top of my head.
 
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