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Overheating problems - your suggestions?

73azbronco

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Nov 11, 2007
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I too would consider going a normal water pump, reference article I linked, you may be cavitating the coolant and not moving it at all.
 

bteutsch

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Jan 11, 2009
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873
I don't blame you, I saw it happen... Sooo not necessary.


Sent from my iPhone using Tapatalk
 
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Timmy390

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Jan 1, 2011
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5,609
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Conway, AR
If it was fine till the A/C condenser was added, my vote is for airflow being the issue. The added condenser is blocking air and or due to the thickness of the condenser and radiator combo, the fan can't pull the needed air.

Tim
 

blubuckaroo

Grease Monkey
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Jun 11, 2007
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Ridgefield WA
I can agree that airflow is the likely culprit, but if that's the case, how did you ever get the A/C charged? The head pressure must have been off the chart.
If you had a shop do that part...shame on them!
 

Rustytruck

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Joined
Feb 24, 2002
Messages
10,875
If it was a water pump or radiator issue it would be a problem at freeway speeds. engine turning faster under power making 10 times the heat and yet the radiator can cool it. so either your getting too much heat from a transmission cooler if your running one. fan too slow, water pump too slow or the fan isnt pulling enough air. No car should overheat at Idle. the engine isnt producing enough heat to warrant this problem.
 

DirtDonk

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Agree, but that's also why I was asking about what else was done at the same time. The most obvious thing is the condenser changing the air flow, but was the radiator changed or relocated to accommodate this? Were the coolant hoses changed in any way? If the water pump came with the crate engine, then we can at least assume for now that it's the correct orientation and in reasonably good condition. I hate assuming of course, but just to narrow the search down a bit at first...;)

The fan would still be a good place to check, even though it's not given you trouble until now. Most of the time when a fan is on backwards even a stock engine with no A/C will not cool properly. So it's usually discovered long before any additions come along.
But a weaker fan might have been borderline before the change, but now just can't keep up with the demand of pulling through two radiators.

How old is the radiator I think someone asked? Even new engines can puke casting sand and other junk into the cooling system, and things like that tend to coagulate at the bottom of the radiator and block flow through several layers of tubes. A stock size radiator is more than enough for a mild engine, but a half-clogged one won't be.

The air dam is an almost universally good idea, but especially when you have trouble with air flow. It's not a cure-all for other issues, but you are at least eliminating one layer of compromise. And adding a nice tool tray at the same time doesn't hurt!
http://www.wildhorses4x4.com/category/s?keyword=air+dam
Also mentioned was removing or louvering or meshing your inner wheel wells. This is also a great idea.
However, both of those air-flow improvements benefit an EB at higher speeds and low. Especially with a weaker fan. They still improve low-speed air flow, but not as much as at higher speeds. In theory at least. Lots of owners will tell you that their Broncos stopped overheating when they removed the hood and put it on the roof! Air flow.
Some have benefited the same from the mesh at low speeds, but not every overheating issue is fixed by doing that either. And you don't seem to have an issue at higher speeds as you've said it cools down quickly once you start moving again.

Have you also attempted to simply rev the engine up while sitting still and overheating? If that works, you could still have an air flow issue, but could also be a coolant flow issue.
I know... Overheating is such a bitch!

But a tuneup is paramount. You've been driving it for years without one, and perhaps it doesn't need it due to electronic ignition and a well-tuned carburetor. But you never know. You could have been on the borderline of running hot before, due to a poor ignition timing setting for example, and putting in the A/C simply put it over the edge.

I am now running a 5.0 with A/C, Explorer mechanical fan and stock radiator. On cool days it rarely goes over 185. On warmer days it goes right to 195 and pretty much stays there except under special circumstances. When it goes up maybe 5 more degrees at the most. Haven't been running it for all that long yet, but so far that's what I've seen.
Oh and it's also got a winch on the front, which adds one more layer of air disturbance ahead of the radiator.
It might be the fan, but I'd bet a TON of that consistent cooling is due to the finer tuning of the EFI and computer controlling the timing.
If you ever have a chance to watch real-time timing changes through an OBDII scanner, you'd be surprised to see just how much time the ignition stays at 20° or more. Only coming down under heavier use of the accelerator.

So if you do nothing else, a quick timing check and change might at least be worth the experiment time it takes to do it.
And how is your PCV valve? Checked it lately?

In your location it can certainly get warm. But what gas do you get there? Ethanol mixes? I wonder how that's effecting heat output? No idea, but putting it out there in case someone knows the science behind it.

Good luck.

Paul
 

BRONCOchild

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Sep 4, 2005
Messages
2,029
Time to sell the whole truck. I'll give you a strong $2000 for it. LOL...jk...best of luck.
 

Boss Hugg

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KSM, I'll tell this story, suggesting the easiest test to do first and you're creative enough to make something work to check it out yourself.

I put an external engine oil cooler on my super duty. One day I was looking at something and took the air dam over the top of the coolers off and layed it in the backseat. Next day I drove it 60 miles roundtrip. Normal oil temp is 195-200. after 60 miles without the air dam, it was 230 and growing quickly and 70 degrees outside.

try to put an air dam on it. At speed theres enough air forced into the grill that gets thru the radiator. Sitting still its VERY easy for air to circle back around the core support and heat up the air going into the condenser and radiator. If this is the issue, your AC will work much better too at low speeds.
 

Rox Crusher

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Dec 13, 2008
Messages
2,772
If you change to a 195 degree thermostat test it prior to installing it.

This would also allow you to see if there is any gunk built up on the existing thermostat restricting flow and also could be an indicator of the theory that your radiator is clogged up.

I also believe the air dams on top of the core support to the grill helps with mine.
 
OP
OP
Ksm

Ksm

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Apr 29, 2013
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1,252
Here are some photos. Now that I'm looking at it focusing on air flow...is this automatic transmission cooler that was mounted in front of the radiator core support blocking the air? Air would have to get around this thing through the condenser before even getting to the fan. Could this be the issue?

I'm going to go ahead and order the 7 blade fan and the 195 thermostat. Unless y'all see something in the photos that will point to a different problem.
 

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Rox Crusher

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I think you solved your own mystery.

The auxiliary trans cooler looks to be taking up a lot of surface area in front of radiator.

This was exasperated by adding air conditioning condenser.

There is another style of aux cooler that you could mount in front of the engine / frame cross member. Aluminum cylinder jobby.
 

Rox Crusher

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Dec 13, 2008
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Also, looks like you have a stock shroud but we can't see how far into the shroud the fan is. It may be in too far.

You want the fan blades half in - half out.

I would get the OEM 7 blade fixed blade fan with the right spacer between it and the water pump pulley.
 

Slowleak

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Sep 12, 2013
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3,732
Loc.
Georgia
Yup.... that cooler needs to move. Seven blade fan should pull more air and make your A/C run colder too. I'm in Atlanta and run a 5 blade fan, stock radiator, and 195 thermostat. Mine runs cool when idling with the A/C on.

Just make sure the fan clears your compressor pulley. I noticed it's a double groove.
 

jw0747

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Need a pic of the fan and how it fits in the shroud. Is the fan a solid blade or a flex blade? Solid blade pulls more air at engine idle speed.
A solid 7-blade fan that fits half in and half out of the shroud would probably fix your problem.
 
OP
OP
Ksm

Ksm

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Need a pic of the fan and how it fits in the shroud.

Ok I'll get that in the morning. It's in there pretty tight with not much clearance. Is this something I will need to change when I get the new 7 blade fan in?
 

Rox Crusher

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Ok I'll get that in the morning. It's in there pretty tight with not much clearance. Is this something I will need to change when I get the new 7 blade fan in?

I think your fan is too far into the shroud. Probably because the fan spacer is too long. But as mentioned previously, you also need to make sure using a shorter one won't put the fan into the pulley on the a/c compressor.

Search "ford 302 fan spacer" on eBay and you will see an ad that shows several versions of used OEM fan spacers for reference.
 

jw0747

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Pic #4 with the hand and flashlight. Take a pic on that same side with your camera about even with your air cleaner but pointed forward showing the fan and shroud.

You need to get the correct fan and spacer so that it fits properly in the shroud then determine if your engine runs cooler with those changes before you consider moving the trans cooler.
 
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