You've got a champion radiator with plastic tanks? I thought they were all welded aluminum, which was one of their selling points especially for the price. Mine is.
CK5
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Cooling System Overhaul - Stumped and Frustrated
- Thread starter dhcomp
- Start date
bp71k5
3/4 ton status
Subscribed since I'm on radiator #3 with similar issues.
gonefishin
1/2 ton status
wow I have read this whole thread today.... was the overheating ever fixed?
We had a 89 3/4 ton suburban growing up with a 454. It would overheat every time we pulled the travel trailer. At the time it was only a couple years old. Like you everything was replaced except for the engine. Overheating never stopped.
I think your radiator is too small. even though it is stock size I don't think you are getting enough surface area with airflow. I say get the widest radiator you can even if you have to mod some stuff to make it fit. Surface area is better than thickness imo.
I have a 4 core brass radiator that I used in my 91 c1500. I don't remember the width or the year it was for, but it was for a 1 ton 454 truck. My truck never overheated after installing that. I have pulled a huge travel trailer in 100 degree heat up and down some good "hills" not mountain passes. It never would get past 210. Before the bigger radiator I tried a new stock replacement radiator and it would get almost to the red while pulling.
We had a 89 3/4 ton suburban growing up with a 454. It would overheat every time we pulled the travel trailer. At the time it was only a couple years old. Like you everything was replaced except for the engine. Overheating never stopped.
I think your radiator is too small. even though it is stock size I don't think you are getting enough surface area with airflow. I say get the widest radiator you can even if you have to mod some stuff to make it fit. Surface area is better than thickness imo.
I have a 4 core brass radiator that I used in my 91 c1500. I don't remember the width or the year it was for, but it was for a 1 ton 454 truck. My truck never overheated after installing that. I have pulled a huge travel trailer in 100 degree heat up and down some good "hills" not mountain passes. It never would get past 210. Before the bigger radiator I tried a new stock replacement radiator and it would get almost to the red while pulling.
Never really resolved it. Got another radiator on the way as a warranty replacement.
If i can convince myself to take the grill off, i'll remove the coolers blocking the airflow, and see what happens.
If i can convince myself to take the grill off, i'll remove the coolers blocking the airflow, and see what happens.
The problem is that the opening in the core support only allows so much "airflow". Even the smallest radiators installed cover the opening in the core support.
Capacity is the only difference I can tell from the different radiator sizes. Yes, the shroud on all of them (that I am aware) will allow the fan to attempt to pull air across the entire radiator core, but it won't be as efficient anywhere outside of the opening in the core support. Thicker radiators, to a point, may help.
My suspicion is that GM used the larger radiators mainly to get more coolant in the system, not because the swept area of the radiator was larger, even though it is. A side benefit is of course the surface area, regardless of how effective airflow is.
Brian, your radiator is a champion also?
Capacity is the only difference I can tell from the different radiator sizes. Yes, the shroud on all of them (that I am aware) will allow the fan to attempt to pull air across the entire radiator core, but it won't be as efficient anywhere outside of the opening in the core support. Thicker radiators, to a point, may help.
My suspicion is that GM used the larger radiators mainly to get more coolant in the system, not because the swept area of the radiator was larger, even though it is. A side benefit is of course the surface area, regardless of how effective airflow is.
Brian, your radiator is a champion also?
Who did you buy the brass one from?
gonefishin
1/2 ton status
It was from a local radiator shop. I am not sure if they are even still in business.. if i remember correctly it was a used radiator that he had refurbished. I have it in my attic, i can take some measurements and pictures if you want
Sometimes it's the automatic transmission that makes a engine run hot when towing...and adding an external cooler solves the problem,if it only appears when towing...
I dislike plastic tanked radiators,unfortunately that seems to be about all ypu can buy now,unless you go with an all aluminum one like a Griffin,etc...
I like old school brass ones,that can be repaired at home with some solder and flux...and usually dont need fixing for a good 10+ years at least..the few brass ones I've seen lately from China suck too though,they are probably made of recycled crap full of impurities...friend put one in a Jeep recently and it only lasted 6 months before it started weeping..
I dislike plastic tanked radiators,unfortunately that seems to be about all ypu can buy now,unless you go with an all aluminum one like a Griffin,etc...
I like old school brass ones,that can be repaired at home with some solder and flux...and usually dont need fixing for a good 10+ years at least..the few brass ones I've seen lately from China suck too though,they are probably made of recycled crap full of impurities...friend put one in a Jeep recently and it only lasted 6 months before it started weeping..
y5mgisi
1 ton status
Rock auto still offers the big all brass radiator but I think it's like almost $400!
I had one of those. I forget why i switched to AL. Its probably in this thread.
That being said, the factory style brass one's core is about 1" thick. This AL core is about 4" thick. Huge differene.
I think there is a pic in this thraed.
y5mgisi
1 ton status
This is the one i'm talking about. Listed for a 90 2wd 454 burb. Doesnt say number of rows, but says 2.5" thick.
http://www.rockauto.com/catalog/moreinfo.php?pk=3611034&cc=1301454&jnid=529&jpid=3
http://www.rockauto.com/catalog/moreinfo.php?pk=3611034&cc=1301454&jnid=529&jpid=3
You could try a diesel radiator. They are 4" to 6" wider. That would help as much as going thicker. If you look at the core support you can see the matching set of holes for the radiator bracket several inches closer to the driver side headlight.
My K5 came with a 6.2L so it had a wider radiator. When I swapped in a 350 gasser I had to block the radiator in the winter or it would never warm up.
My K5 came with a 6.2L so it had a wider radiator. When I swapped in a 350 gasser I had to block the radiator in the winter or it would never warm up.
4xcrazy
3/4 ton status
Ya know, I'm gonna be that guy I guess.. I've made comments in here before, I'm sure, not gonna go back through this decent sized thread.
I lived in Arizona with those 110° plus summers, the burb when I got it would get a bit warm especially when trying to run the ac, when it worked. This was with a factory style 3 row radiator.
After I replaced the radiator with a "heavy duty cooling" 4 row radiator, not extra wide, and a heavy duty fan clutch, it barely makes it to thermostat temp. Took it back to Indiana with the much colder climate, it never would hit thermostat temp, just kept over cooling.
I'm still going to say that there is something going on with the engine creating an overheating issue. I seriously believe that if a new heavy duty equipped cooling system can't keep it cool, it's not the cooling system, but at least it's seriously trying.
You shouldn't have to be forced to purchase a high performance rated radiator to keep an engine cooled for mild trailer pulling or as you stated previously, pulling it's own weight.
Also to add, the setup I had is still utilizing the factory located engine oil cooler and an aftermarket transmission cooler that is the same size as the engine oil cooler, on the passenger side, both in front of the radiator..
I lived in Arizona with those 110° plus summers, the burb when I got it would get a bit warm especially when trying to run the ac, when it worked. This was with a factory style 3 row radiator.
After I replaced the radiator with a "heavy duty cooling" 4 row radiator, not extra wide, and a heavy duty fan clutch, it barely makes it to thermostat temp. Took it back to Indiana with the much colder climate, it never would hit thermostat temp, just kept over cooling.
I'm still going to say that there is something going on with the engine creating an overheating issue. I seriously believe that if a new heavy duty equipped cooling system can't keep it cool, it's not the cooling system, but at least it's seriously trying.
You shouldn't have to be forced to purchase a high performance rated radiator to keep an engine cooled for mild trailer pulling or as you stated previously, pulling it's own weight.
Also to add, the setup I had is still utilizing the factory located engine oil cooler and an aftermarket transmission cooler that is the same size as the engine oil cooler, on the passenger side, both in front of the radiator..
I totally agree with you.
I just gotta figure out what that is. Ive got a bit of rough running on startup, but other than that, it runs good.
Motor has about 25k on it since new, probably getting to be time for a full tuneup. Plugs, cap, rotor, etc.
I just don't know what else to check at this point . Timing is set correctly, all sensors work, heated 02, etc.
Best guess i have is O2 location throwing something off.
O2 just isn't going to be a factor under heavy load. Even if it was, the relocated sensor would read fine with a constant load.
Got the replacement radiator.
Overflow nipple came uninstalled, with fubar'd aluminum threads on both the radiator and fitting. That install went awesome.....
Ended up pounding a custom tapered brass 1/4" barb into the hole. Hope it holds.
For the heater hose, instead of having a hose connection on the radiator, with internal 1/8" NPT threads, they shortened the bung, so there is nothing to hose clamp to.
$40 at lowes later, i have some ghetto contraption to convert 1/8" NPT to work with a 3/4" hose, and it leaks.
WTF is the best way to convert 1/8" NPT to 3/4" barb? Yes, flow sounds totally illogical, but with the short bung they gave me, i have no other choice.
Not happy.
2 hr install turned into 3 days with parts store runs to have a leaking setup.
Calling champion tomorrow.
Overflow nipple came uninstalled, with fubar'd aluminum threads on both the radiator and fitting. That install went awesome.....
Ended up pounding a custom tapered brass 1/4" barb into the hole. Hope it holds.
For the heater hose, instead of having a hose connection on the radiator, with internal 1/8" NPT threads, they shortened the bung, so there is nothing to hose clamp to.
$40 at lowes later, i have some ghetto contraption to convert 1/8" NPT to work with a 3/4" hose, and it leaks.
WTF is the best way to convert 1/8" NPT to 3/4" barb? Yes, flow sounds totally illogical, but with the short bung they gave me, i have no other choice.
Not happy.
2 hr install turned into 3 days with parts store runs to have a leaking setup.
Calling champion tomorrow.
That sucks with the radiator. It seems like at least initially, they were turning out fairly good quality stuff, at least in terms of visible fit and finish. The problems you describe seem to indicate either you were sold something that at best should have been sold cheaply with a disclaimer, or their QC has gotten that bad. You just have to scratch your head when things like that happen. It's just as easy to do something right, and if it's that screwed up, how can they possibly think it's not going to cause issues when its sold?
I forgot about the ridiculously small heater hose fitting. IIRC even on the earlier Champion radiators they were pretty restrictive. I'd hate to do it for this radiator alone, but have you considered just plumbing the return into the water pump? That's why the pump has pipe plugs up top. Outside of that, only way I can think of to adapt is run a short length of 1/8" pipe, and then an adapter to allow a hose barb to thread on. But that's a LOT of work and connections, for a too small diameter fitting in the first place. I know my Dad had no complaints about heat running the Champion, but it sure seems like it would work better if you had more flow.
I forgot about the ridiculously small heater hose fitting. IIRC even on the earlier Champion radiators they were pretty restrictive. I'd hate to do it for this radiator alone, but have you considered just plumbing the return into the water pump? That's why the pump has pipe plugs up top. Outside of that, only way I can think of to adapt is run a short length of 1/8" pipe, and then an adapter to allow a hose barb to thread on. But that's a LOT of work and connections, for a too small diameter fitting in the first place. I know my Dad had no complaints about heat running the Champion, but it sure seems like it would work better if you had more flow.
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Never routed through the water pump. Any idea what the thread sizes are? I like that idea. I've got an 1/8npt adapter, but it takes 5 connections and bushings and crap to get to 3/4 barb, and now it's leaking.
Would a 3/4" NPT to 1/8" NPT bushing like this work?..you can get 3/4" female NPT barbed fittings that will screw over the bushing..
