Need advice from the Bullnose Braintrust.

[Cbarnes]

As y’all know, I got the flex plate replaced on Bubba. Been driving him quite a bit. A/C is working great, truck runs great and all is good as long as you are running down the highway. But when I come into town or have to stop at a stop sign the water temp climbs higher than I would like. I have replaced the thermostat with a 165 degree thermostat. But it is still getting warmer than I would like. I would like to replace the factory radiator with a 3 or 4 row aluminum with electric fans. But am having a difficult time finding a respectable manufacturer (Champion, or Mishimoto) in stock. Can y’all recommend a different manufacturer or something that I can do to keep the temp from climbing so much during low speed driving?

Thanks,

Carl

[Gary Lewis]

I don't think electric fans should be part of Step 1 in solving this. I believe that complicates things. Big Blue handles this 100F temp just fine with his mechanical fan unless you sit and idle for maybe 10 minutes, and even then running the engine just a bit faster moves both air and water and cools him down. I would concentrate on the radiator first, and later if you see a need for electric fans do that step.

So, does your fan come on strong when the temp comes up? It should make a lot of noise and pull a lot of air at an 800 RPM idle when the coolant temp is up there.

And, are you sure it is getting hot? Do you have an accurate gauge on it?

Last, when I was looking for a Champion 4-row they did have 3-row radiators in stock, and I think that would probably solve the problem - if the fan is working correctly and if the temp is truly getting up too high, like 220F.

[Cbarnes]

I don't think electric fans should be part of Step 1 in solving this. I believe that complicates things. Big Blue handles this 100F temp just fine with his mechanical fan unless you sit and idle for maybe 10 minutes, and even then running the engine just a bit faster moves both air and water and cools him down. I would concentrate on the radiator first, and later if you see a need for electric fans do that step.

So, does your fan come on strong when the temp comes up? It should make a lot of noise and pull a lot of air at an 800 RPM idle when the coolant temp is up there.

And, are you sure it is getting hot? Do you have an accurate gauge on it?

Last, when I was looking for a Champion 4-row they did have 3-row radiators in stock, and I think that would probably solve the problem - if the fan is working correctly and if the temp is truly getting up too high, like 220F.

Thanks Gary,

The fan clutch appears to be working fine, and looks to be fairly new. As far as an accurate gauge, not at this time. Just going by what the factory gauge is showing. Where is the best place to put the temp probe for a new temp gauge?

[Littlebeefy]

Thanks Gary,

The fan clutch appears to be working fine, and looks to be fairly new. As far as an accurate gauge, not at this time. Just going by what the factory gauge is showing. Where is the best place to put the temp probe for a new temp gauge?

First off, new parts aren’t always working parts. I’ve had brand new parts that were defective plenty of times. Test your fan clutch. Make sure you’re getting more resistance when it’s hot.

Second, I agree with Gary on the electric fans. You shouldn’t need them if everything is working correctly. Have you verified that you have the correct shroud and the correct fan for the shroud? Is the fan properly spaced in relation to the shroud? If you want to know what they should be, you are on the right website. If you think airflow is the culprit that is where I would start.

Have you bled your radiator to ensure there is no air trapped in the block? Have you checked pressure in the coolant return line by hand? Are the heater hoses getting hot? Have you popped the cap on your radiator and confirmed that water is coming in?

You said it’s getting “warmer than you like”. What temperature does it reach?

I’m definitely not an expert but I’m hoping that If I throw out areas to check and you come back with something noteworthy it might stimulate some discussion on causes.

Also I have a Champion radiator. It is a 3 row and is the “stock replacement” for a 351W. I have it cooling my high compression 460 without a problem. I have a Derale fan and a HD fan clutch (although I don’t necessarily recommend that) and the stock shroud for the 460 in an F series. My coolant runs at 190 (I have a 185 thermostat) and my oil runs at 225 in the summer in Georgia. I don’t see any reason that a 3 row Champion won’t work well for you.

[Littlebeefy]

First off, new parts aren’t always working parts. I’ve had brand new parts that were defective plenty of times. Test your fan clutch. Make sure you’re getting more resistance when it’s hot.

Second, I agree with Gary on the electric fans. You shouldn’t need them if everything is working correctly. Have you verified that you have the correct shroud and the correct fan for the shroud? Is the fan properly spaced in relation to the shroud? If you want to know what they should be, you are on the right website. If you think airflow is the culprit that is where I would start.

Have you bled your radiator to ensure there is no air trapped in the block? Have you checked pressure in the coolant return line by hand? Are the heater hoses getting hot? Have you popped the cap on your radiator and confirmed that water is coming in?

You said it’s getting “warmer than you like”. What temperature does it reach?

I’m definitely not an expert but I’m hoping that If I throw out areas to check and you come back with something noteworthy it might stimulate some discussion on causes.

Also I have a Champion radiator. It is a 3 row and is the “stock replacement” for a 351W. I have it cooling my high compression 460 without a problem. I have a Derale fan and a HD fan clutch (although I don’t necessarily recommend that) and the stock shroud for the 460 in an F series. My coolant runs at 190 (I have a 185 thermostat) and my oil runs at 225 in the summer in Georgia. I don’t see any reason that a 3 row Champion won’t work well for you.

NPD sells the Cold Case radiators. I have not tried them but I generally trust NPD. Maybe someone else has. It says it is 2 row but cools better than 3 or 4 row:

https://www.coldcaseradiators.com/product/80-84-ford-broncof-series-truck-radiator

[grumpin]

I agree with Gary and Chad on the electric fans.

Hopefully you can find an aluminum radiator. I put a 3 row on the 86 I used to have..

[Pete Whitstone]

I just installed a KKS Motorsport radiator in my truck, but I only have about one week and a hundred miles of driving on it so far. But I am happy with the fitment and the general quality of it. It holds a lot more water than the 1" core unit it replaced, so it tends to heat up slower, and cool down a little slower, but it seems to be doing the job just fine so far, even in this heat. I paid $387 for it in May, and now I see they are priced at $280. Of course.

But my truck is a 5.8, not a 460 like yours. I'm not sure what the differences would be in the radiators. I got it from Radiator Express, no problems with the order or delivery.

[85lebaront2]

I just installed a KKS Motorsport radiator in my truck, but I only have about one week and a hundred miles of driving on it so far. But I am happy with the fitment and the general quality of it. It holds a lot more water than the 1" core unit it replaced, so it tends to heat up slower, and cool down a little slower, but it seems to be doing the job just fine so far, even in this heat. I paid $387 for it in May, and now I see they are priced at $280. Of course.

But my truck is a 5.8, not a 460 like yours. I'm not sure what the differences would be in the radiators. I got it from Radiator Express, no problems with the order or delivery.

Ford in their infinite wisdom "used one size fits all" gas V8 radiators from the 1984 change through the 1997 F250/350 models. This meant the a 302 and a 460 have the exact same radiator.

Darth has only really given me a problem one time in the 28 years I've owned him, about 3 years ago, stuck in a mess trying to get through the Downtown Tunnel between Portsmouth and Norfolk VA. It was one of those days where the two sides of the approach road were really backed up, temperature was probably a little over 100° and humidity was in the mid to high 90s.

Never boiled over, but, temp was well up into the high end, computer had advanced the timing and raised the idle. Any time I was sitting not moving I was in Neutral so I could raise the rpm higher my self. My NASA wind tunnel emulator (fan) was definitely moving air as you could hear the roar at around 8-900 rpm.

I think that was the hottest I had seen, before that was one time going up US301 SE of DC towing our 30 ft 5th wheel where you are pretty much driving past shopping centers on both sides from Upper Marlboro to Bowie. Every time we were stopped at a light and pulled away, the fan sounded like a jet taking off for maybe 1/2 mile then it would taper off.

[Rusty_S85]

As y’all know, I got the flex plate replaced on Bubba. Been driving him quite a bit. A/C is working great, truck runs great and all is good as long as you are running down the highway. But when I come into town or have to stop at a stop sign the water temp climbs higher than I would like. I have replaced the thermostat with a 165 degree thermostat. But it is still getting warmer than I would like. I would like to replace the factory radiator with a 3 or 4 row aluminum with electric fans. But am having a difficult time finding a respectable manufacturer (Champion, or Mishimoto) in stock. Can y’all recommend a different manufacturer or something that I can do to keep the temp from climbing so much during low speed driving?

Thanks,

Carl

Fact is that you dont have the issue running down the highway but do when you are sitting still rules out the radiator as the culprit. It is an airflow issue which points to the fan not moving enough air.

If its a clutch fan verify the clutch is good.

I have a OE 5 bladed flex fan and I actually blew the upper hose once and it took nearly 15 minutes for the temp gauge to start to reach the high side of normal. The truck with a 180* thermostat runs on the low side of normal even on a 100* day. The stock HD radiator is well over big enough to keep your engine cool.

Now if you had a radiator problem such as a blocked radiator or stopped up radiator it would over heat on the highway as well due to lack of coolant flow. Same thing with a water pump not flowing enough water.

[Rusty_S85]

NPD sells the Cold Case radiators. I have not tried them but I generally trust NPD. Maybe someone else has. It says it is 2 row but cools better than 3 or 4 row:

https://www.coldcaseradiators.com/product/80-84-ford-broncof-series-truck-radiator

If I go with an aluminum radiator to replace my OE copper one I will be gonig with the Cold Case. The biggest selling point for me is the OE appearance which I can shoot some radiator black on from eastwood and make it look OE.

The other thing is with aluminum it was found fewer tubes that are wider actually cool better than more tubes that are narrow. Something to do with the turbulence created by the gaps between the tubes that can hinder airflow.

Summit explains it a bit better than I can this is what they say below.

Tube Size

The tube size listed is the width of the tube. Wider tubes have more surface area. This means they can dissipate more heat.

How does this affect performance?

In the old days, with copper/brass radiators, more rows meant more cooling. However, it also made the radiator thicker. This adds air restriction, making it less efficient. It is also harder on the fan. For mechanical fans, this means more parasitic power loss.

More rows also means the rear tubes are less effective than the front ones. As air flows through the core, it picks up heat. By the time it gets to the back row, it is warmer than when it started. This means less heat can be removed from the rear tubes. As more rows are added, this becomes a bigger issue.

Aluminum radiators have helped to solve these problems. Because aluminum is stronger, the tubes can be wider. This means more contact area without significantly increasing the thickness of the radiator.

Its why I wouldnt sweat running a 2 row aluminum radiator like Cold Case`s over the OE replacement copper radiator that has 3 rows. It will just be an upgrade in cooling capacity. For me how ever I am weighing costs. New radiator or just pay to have my old copper one cut open and cleaned out for my new engine.