Yes sir, as far as I know. My father (P.O.) actually did the swap. But from what I remember and have seen they just bolt right in.
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Meet "Murphy" the '84 K5
- Thread starter kis2
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Yes sir, as far as I know. My father (P.O.) actually did the swap. But from what I remember and have seen they just bolt right in.
kis2
1/2 ton status
thank you for the info, maybe that's what I should be looking for then.
Can't see any of the pictures. My fault.
But sounds like your radiator is an unknown?What "size" is it? GM used about 8 million different radiators in these trucks. The normal small block radiator is nearly flush with the top of the core support. The brackets bolt into the top of the core support. The small (short) radiator has mounts the bolt to the back side of the core support, and they drop down about 3" from the top edge of the core support. Not sure what that was used on, but I have a couple of those brackets, so I know they are out there. I doubt those have any place on a 350 equipped truck.
There are also two row radiators that are "tall", I can see those being a bit iffy on cooling. I ran one for awhile, but I don't have an automatic, no AC, etc., so I add very little heat outside what the engine does.
How about all the basics? Is the fan shroud correct? Is the fan mating up with the fan shroud correctly? Do you have an air dam under the bumper? I doubt any of those are the real culprit, but definitely worth checking into. How about your heater hoses? Never seen those cause a heating problem, but I've certainly heard them being hooked up wrong. Radiator or water pump fitting is the heater "outlet" (either way, both low pressure), the intake manifold is the heater "inlet".
Anymore, if you don't know the radiators condition, it's probably just best to replace it. As much work as you've done I'm sure you'll have no problem making a cheap aluminum radiator fit, like a Champion. Normally take some work on the mounting spots (a bit too short) and the hoses might be a different diameter, but for the cost, it's not a terrible piece. I am surprised the Griffin was so bad. Perhaps they sent you the wrong one? I had worked with their engineers a tiny bit trying to come up with a radiator for myself, and they were so helpful I'm surprised they'd turn something out like you described, especially with these trucks as common as they are. With as many different radiators as there are for the trucks (three different radiator brackets alone for '81-87/91 AFAIK)
My experience with "bad" radiators has been that they wouldn't keep the motor cool, cruise and idle, and you could see the corrosion on the rows of tubes. It didn't look terrible, but I took some vinegar to it, and a bunch of junk came out. Still didn't work right, so I replaced it. That radiator was horrible. You might get a better idea of the condition if you take the lower hose off and try to look at the cores that way, but again, my experience has been that even if they look decent, they may not flow for a darn. I only know of one place that can actually flow test radiators, and IMO that's the only way short of taking them apart, to make sure they are good. And I would almost guarantee a Champion is cheaper than getting a copper/brass radiator re-cored.
In your case, since you mention overheating at speed, when airflow through the radiator is at its best, it's either an airflow issue (restriction to flow) or a radiator issue IMO. If you bring the engine RPM's up at idle, does it still stay at the thermostat temp, or at least "normal" idle temp? I noticed last trip out with my truck, while climbing hills under 25MPH, the temperature seemed to hover right around 210. Any faster and the temp would go back to 195*. Any slower and the fan would come on. But once the fan came on, temperature did not increase. It also wasn't but maybe 85* out.
As to the "big block" radiator, as long as it's not the one that's ~34" wide it will fit with no problem. But the big block radiator has a different shroud, which means the small block fan won't fit it quite right (since the 350 is not as long as a 454) and you may need to space it.
My Dad put a Champion 3 row radiator in his truck (K20, 454), and while it's smaller than the radiator he took out (the Champion appears to be small block height, the big block radiator is apparently a bit taller) so far he hasn't had any cooling issues.
I actually picked up a Champion made for the '84-90 Corvette, and I'm going to stuff it in the K5 where the AC condenser fits. That's a 30x17 hole. Roughly 20% reduction in size over whats in it now. Hopefully it works.
But sounds like your radiator is an unknown?What "size" is it? GM used about 8 million different radiators in these trucks. The normal small block radiator is nearly flush with the top of the core support. The brackets bolt into the top of the core support. The small (short) radiator has mounts the bolt to the back side of the core support, and they drop down about 3" from the top edge of the core support. Not sure what that was used on, but I have a couple of those brackets, so I know they are out there. I doubt those have any place on a 350 equipped truck.
There are also two row radiators that are "tall", I can see those being a bit iffy on cooling. I ran one for awhile, but I don't have an automatic, no AC, etc., so I add very little heat outside what the engine does.
How about all the basics? Is the fan shroud correct? Is the fan mating up with the fan shroud correctly? Do you have an air dam under the bumper? I doubt any of those are the real culprit, but definitely worth checking into. How about your heater hoses? Never seen those cause a heating problem, but I've certainly heard them being hooked up wrong. Radiator or water pump fitting is the heater "outlet" (either way, both low pressure), the intake manifold is the heater "inlet".
Anymore, if you don't know the radiators condition, it's probably just best to replace it. As much work as you've done I'm sure you'll have no problem making a cheap aluminum radiator fit, like a Champion. Normally take some work on the mounting spots (a bit too short) and the hoses might be a different diameter, but for the cost, it's not a terrible piece. I am surprised the Griffin was so bad. Perhaps they sent you the wrong one? I had worked with their engineers a tiny bit trying to come up with a radiator for myself, and they were so helpful I'm surprised they'd turn something out like you described, especially with these trucks as common as they are. With as many different radiators as there are for the trucks (three different radiator brackets alone for '81-87/91 AFAIK)
My experience with "bad" radiators has been that they wouldn't keep the motor cool, cruise and idle, and you could see the corrosion on the rows of tubes. It didn't look terrible, but I took some vinegar to it, and a bunch of junk came out. Still didn't work right, so I replaced it. That radiator was horrible. You might get a better idea of the condition if you take the lower hose off and try to look at the cores that way, but again, my experience has been that even if they look decent, they may not flow for a darn. I only know of one place that can actually flow test radiators, and IMO that's the only way short of taking them apart, to make sure they are good. And I would almost guarantee a Champion is cheaper than getting a copper/brass radiator re-cored.
In your case, since you mention overheating at speed, when airflow through the radiator is at its best, it's either an airflow issue (restriction to flow) or a radiator issue IMO. If you bring the engine RPM's up at idle, does it still stay at the thermostat temp, or at least "normal" idle temp? I noticed last trip out with my truck, while climbing hills under 25MPH, the temperature seemed to hover right around 210. Any faster and the temp would go back to 195*. Any slower and the fan would come on. But once the fan came on, temperature did not increase. It also wasn't but maybe 85* out.
As to the "big block" radiator, as long as it's not the one that's ~34" wide it will fit with no problem. But the big block radiator has a different shroud, which means the small block fan won't fit it quite right (since the 350 is not as long as a 454) and you may need to space it.
My Dad put a Champion 3 row radiator in his truck (K20, 454), and while it's smaller than the radiator he took out (the Champion appears to be small block height, the big block radiator is apparently a bit taller) so far he hasn't had any cooling issues.
I actually picked up a Champion made for the '84-90 Corvette, and I'm going to stuff it in the K5 where the AC condenser fits. That's a 30x17 hole. Roughly 20% reduction in size over whats in it now. Hopefully it works.
kis2
1/2 ton status
thanks for looking dyeagar. going up the hill at 30mph or under is where I consider it to really overheat, otherwise (faster) it just gets warm under the load. pulling over at sitting still at idle and within a minute or two it cools back down to an acceptable level. that's why I believe it is a radiator effeciency issue.
I was pretty disappointed with the griffins fit, but in fairness to their company, I went through Summitt. it was summitts website that told me it would be a direct fit, it was summitts technicians that told me it would be a direct fit, and it simply wasn't close. probably and inch too tall, 1/2 wider than the factory brackets and the hose connection on the passenger side was angled up, perfectly in the way of the transcooler lines. pretty radiator though.
I hadn't heard of champion before, but their website offers me this:
Champion All Aluminum Radiator
3-Row Core
CORE 19” Tall x 28 ¼" Wide
Total 20 ¼” (21 Incl Cap) x 33 1/8” Wide
In 1 ½” driver side/ out 1 9/16” Pass side
Tanks 3” thick
Transmission Cooler Included
Radiator Cap Included
and that's for about half of what I paid for the griffin. I will give it a try for sure.
I was pretty disappointed with the griffins fit, but in fairness to their company, I went through Summitt. it was summitts website that told me it would be a direct fit, it was summitts technicians that told me it would be a direct fit, and it simply wasn't close. probably and inch too tall, 1/2 wider than the factory brackets and the hose connection on the passenger side was angled up, perfectly in the way of the transcooler lines. pretty radiator though.
I hadn't heard of champion before, but their website offers me this:
Champion All Aluminum Radiator
3-Row Core
CORE 19” Tall x 28 ¼" Wide
Total 20 ¼” (21 Incl Cap) x 33 1/8” Wide
In 1 ½” driver side/ out 1 9/16” Pass side
Tanks 3” thick
Transmission Cooler Included
Radiator Cap Included
and that's for about half of what I paid for the griffin. I will give it a try for sure.
kis2
1/2 ton status
they have a four core in the same size! that might be the ticket! 
(even if it is out of stock)
(even if it is out of stock)
TDAWG1
1/2 ton status
Clean looking Ride looks awesome Nice work. Nice soft Top
I will say this about Champion. They are cheaper than Griffin, but there are reasons. It sounds to me like the Griffin (if you are sold the right one lol) is ALWAYS a quality piece. I've heard of people getting a Champion that isn't quite "square", as in the radiator might be warped a bit, probably from the welding processes and being improperly cooled. You know, Chinese QC. Not that its ruined, just not straight.
I have no doubt you can make one fit, just be advised that it *probably* won't fit without a little work. But as I said, my Dad installed one that appeared to be shorter than the BBC radiator he had, so he had to do a bit of work to make the brackets hold it tight. I just measured his old "stock" copper/brass one, and the core came out just under 21" tall, and the mounting flanges came out to just over 21" tall. If that helps you any.
As well, when I mention something, I like to be as forthcoming as possible. I've only measured the volume of the Champion radiator I picked up, and it wouldn't even hold a gallon of water. I'll check the BBC radiator one of these days to compare. Obviously water capacity is irrelevant as long as it gets cold enough when it passes through, but more capacity does give you more of a margin of error. To me less than a gallon is pretty eye opening, but I guess more than half the core is fins and space between tubes.
One last thing. Your problem could also be caused by coolant flow, or lack of it. You put a new water pump in there, they are pretty well near bulletproof, but I'm sure someone can turn out a bad piece, or make them with cheap parts. I doubt that's your problem due to the conditions when it overheats, but need to have that out there. Since your radiator right now you aren't sure of condition, you wouldn't be wrong in replacing it whether or not it's the actual issue. When radiators are starting to flow bad, it's because the rows are getting plugged with corrosion. And that normally starts to lead to pinhole leaks in the rows of tubes. Even if it still cooled, leaks are no good!
Guy on ebay selling champions I bought from is this one http://stores.ebay.com/Atomic-Radiator with shipping he was the cheapest I found. Box came quick, no hassles. I've seen the Champions come from two different vendors now, both were in the same style box.
I have no doubt you can make one fit, just be advised that it *probably* won't fit without a little work. But as I said, my Dad installed one that appeared to be shorter than the BBC radiator he had, so he had to do a bit of work to make the brackets hold it tight. I just measured his old "stock" copper/brass one, and the core came out just under 21" tall, and the mounting flanges came out to just over 21" tall. If that helps you any.
As well, when I mention something, I like to be as forthcoming as possible. I've only measured the volume of the Champion radiator I picked up, and it wouldn't even hold a gallon of water. I'll check the BBC radiator one of these days to compare. Obviously water capacity is irrelevant as long as it gets cold enough when it passes through, but more capacity does give you more of a margin of error. To me less than a gallon is pretty eye opening, but I guess more than half the core is fins and space between tubes.
One last thing. Your problem could also be caused by coolant flow, or lack of it. You put a new water pump in there, they are pretty well near bulletproof, but I'm sure someone can turn out a bad piece, or make them with cheap parts. I doubt that's your problem due to the conditions when it overheats, but need to have that out there. Since your radiator right now you aren't sure of condition, you wouldn't be wrong in replacing it whether or not it's the actual issue. When radiators are starting to flow bad, it's because the rows are getting plugged with corrosion. And that normally starts to lead to pinhole leaks in the rows of tubes. Even if it still cooled, leaks are no good!
Guy on ebay selling champions I bought from is this one http://stores.ebay.com/Atomic-Radiator with shipping he was the cheapest I found. Box came quick, no hassles. I've seen the Champions come from two different vendors now, both were in the same style box.
kis2
1/2 ton status
thanks tdawg! looks like you and I have the same front bumper! any problem seeing the blinkers with those additional lights mounted?
dyeager, my truck isn't a show floor truck or anything, so a less than perfect radiator (that is completely functional) would be OK with me, especially to save a couple hundred bucks. I will talk to that ebay seller and see what he knows about the fit and finish. I'm also a big fan of warranties.
I thought about the water pump and kinda came to the same conclusion you did. I don't think it's likely to be the issue, but if I get this radiator in and the problem persists itll be my next course of action.
the 180* tstat appears to be helping though. doesn't even get to 210 going up the hill it would seem. maybe just circling the fluid a little earlier is making the difference. earlier return to the radiator compensating for its ineffeciency perhaps?
dyeager, my truck isn't a show floor truck or anything, so a less than perfect radiator (that is completely functional) would be OK with me, especially to save a couple hundred bucks. I will talk to that ebay seller and see what he knows about the fit and finish. I'm also a big fan of warranties.
I thought about the water pump and kinda came to the same conclusion you did. I don't think it's likely to be the issue, but if I get this radiator in and the problem persists itll be my next course of action.
the 180* tstat appears to be helping though. doesn't even get to 210 going up the hill it would seem. maybe just circling the fluid a little earlier is making the difference. earlier return to the radiator compensating for its ineffeciency perhaps?
I guess theoretically if you start from a lower temperature, and in your case that's most of the time, the colder fluid absorbs more heat (the hotter coolant gets, the less heat it removes from the system, water in particular, since it's a far better coolant than antifreeze)
If the system is borderline to start with, that might just be enough to keep it from getting worse. But of course, even if that's possible, and the 15* lower temp makes a difference, the cooling system is so close to overheating due to poor design/condition that it's simply a band-aid.
If the system is borderline to start with, that might just be enough to keep it from getting worse. But of course, even if that's possible, and the 15* lower temp makes a difference, the cooling system is so close to overheating due to poor design/condition that it's simply a band-aid.
kis2
1/2 ton status
That's what I thought too, use the 180* to tide me over, get an effecient radiator that actually fits here and if I'm super lucky be prepared to swap back to a 195* tstat.
thanks for the advice!
thanks for the advice!
kis2
1/2 ton status
it is worth noting that this radiator and engine were paired together in the original blue truck, with no issues. maybe the extra load of big axles and tires made the difference for the radiators capability?
Lots of variables for the cooling system. The radiator I mentioned before that wouldn't cool worth a darn, was absolutely fine on the motor before I rebuilt the motor. Now of course the rebuilt motor ran hot initially, but even afterward, the radiator never would keep it cool again. Obviously the slight changes made in the rebuild were enough to show the failing of the original radiator.
454 radiator is a direct bolt in as the core support for all square bodies are the same. I have 1 in my Blazer and have never had a heating problem. It is the same height as the 350 radiator, but it is approximately 8" wider. The shroud i use is for a 350. it will stay midway between the first line and the 210 on 100+ day with air going up grade dragging a 19' boat. i have 195 degree stat and it normally rides on the first line of the temp gauge going down the road or in traffic at idle. I will admit that the aluminum are more efficient.
kis2
1/2 ton status
I'm thinking that by the time I find all I need to make a 454, 4 core happen, it'll be quicker and probably close to the same price to get a brand new aluminum. I think I'll go that route.
It is good info to have on hand though, thanks!
It is good info to have on hand though, thanks!
kis2
1/2 ton status
also, I found a pic of the 350 before it went in! shiny new.
![230806_503404008840_7242_n[1].jpg](https://ck5.com/forums/data/attachments/114/114977-77139e5e7d4a2f47e2a350cd5f98f5d5.jpg "230806_503404008840_7242_n[1].jpg")
The BIG radiator is not a "bolt in" (as in no extra work) to all '81+ core supports as an FYI. Some of the earlier core supports had no threads for the drivers side mount that is on the angle. Not sure what year my core support is, but it's that way. The '89 front end on my Dad's truck has the welded on nuts.
Not a big deal, I'm sure it wouldn't be too hard to work around, but just one more of those minute changes I noticed GM made.
GM must have known more capacity helped, that extra portion of the extra-wide radiator isn't exposed to direct airflow.
I have an 85 core support and it did just bolt in for me with the wider insulators and the brackets i got from dealer.
My 1987 V10 has that radiator from the factory with a 350 TBI. It is a non AC truck with an SM465 (no tranny cooler) though. It also had a three blade clutch fan. I suppose GM thought it was sufficient for a stripper model half ton. I never have any overheating problems, but if the radiator goes bad, it is definitely getting replaced with the taller version from one of my parts rigs.
Martin
TDAWG1
1/2 ton status
kis2
1/2 ton status
well, its been rainy recently and I said to myself "ima go see what the trails look like and get some mud on the truck". weather forecast for today was a little bit of rain. grabbed some gear and went out alone, winchless.
mistake.
I got several miles down a trail, and yeah, it'd been raining the whole time and the trail was a bit washed out, but nothing bad. then it turned into a DOWNPOUR
...sitting still my wipers couldn't keep up with the rain. hail started, enough to make the entire ground white. now there were steady rivers rolling down the trail carrying some decent sized sticks. genuinely a small flash flood.
this wasn't at all what I had planned on
..... so I decided the next spot I was able to turn around in I was heading back. after a little more driving I found a fork in the trail that went into a clearing with plenty of room to turn around. however, the trail was basically two small rivers and this point, still raining hard with little pea sized hail.
went to make the three point turn to get turned around and back tires dropped off into the deep grass where nothing but mud was waiting for them. truck stalled at that point, due to the incline of dropping off. restarted, kept foot on gas. tires spun in the mud, threw it everywhere and dug deep, but I was starting to get concerned with how low the rear was and clearance and such. so I got out, locked in the hubs and went to 4-Hi.
threw a bunch of mud and pulled us right out! I would've been stuck out there for sure without these tires and proper 4 wheel drive! the tires did a GREAT job of clearing themselves.
....the pics don't do the trail justice. it's got some good size rocks on it and you can't even see them because of the water! the pic of the tires is post getting out of the mud, look how clear the tread is!
drove back and it was pouring the hole time. crossed four washouts with probably 1.5" of water moving across the trail.
sad part is, you can't even tell I got muddy the rain cleaned it so good! the only evidence is some leaves and sticks oddly placed up high on the truck
I know this isn't anything compared to what some of you guys do, but for a newbie like me in his daily driver who didn't do any planning for a flash flood, it was a lot of fun! I got home and was soaked, but it was a great time.
lessons learned include: plan for the unexpected (I normally do, just a stupid mistake this time) and don't go out alone if you don't have a winch, just in case.
pic 1 is Murphy being awesome post-mud, but look how clean she is despite what we went through! you can see some chunks on the hood and winshield but thats about it.
pic 2 are the tires and the watery trail (this was a nice part even!)
pic 3 is one of the washouts. you can see it destroying that side of the hill but look as it comes across the trail in front of the truck!
mistake.
I got several miles down a trail, and yeah, it'd been raining the whole time and the trail was a bit washed out, but nothing bad. then it turned into a DOWNPOUR
...sitting still my wipers couldn't keep up with the rain. hail started, enough to make the entire ground white. now there were steady rivers rolling down the trail carrying some decent sized sticks. genuinely a small flash flood.this wasn't at all what I had planned on
..... so I decided the next spot I was able to turn around in I was heading back. after a little more driving I found a fork in the trail that went into a clearing with plenty of room to turn around. however, the trail was basically two small rivers and this point, still raining hard with little pea sized hail. went to make the three point turn to get turned around and back tires dropped off into the deep grass where nothing but mud was waiting for them. truck stalled at that point, due to the incline of dropping off. restarted, kept foot on gas. tires spun in the mud, threw it everywhere and dug deep, but I was starting to get concerned with how low the rear was and clearance and such. so I got out, locked in the hubs and went to 4-Hi.
threw a bunch of mud and pulled us right out! I would've been stuck out there for sure without these tires and proper 4 wheel drive! the tires did a GREAT job of clearing themselves.
....the pics don't do the trail justice. it's got some good size rocks on it and you can't even see them because of the water! the pic of the tires is post getting out of the mud, look how clear the tread is!drove back and it was pouring the hole time. crossed four washouts with probably 1.5" of water moving across the trail.
sad part is, you can't even tell I got muddy the rain cleaned it so good! the only evidence is some leaves and sticks oddly placed up high on the truck
I know this isn't anything compared to what some of you guys do, but for a newbie like me in his daily driver who didn't do any planning for a flash flood, it was a lot of fun! I got home and was soaked, but it was a great time.
lessons learned include: plan for the unexpected (I normally do, just a stupid mistake this time) and don't go out alone if you don't have a winch, just in case.
pic 1 is Murphy being awesome post-mud, but look how clean she is despite what we went through! you can see some chunks on the hood and winshield but thats about it.
pic 2 are the tires and the watery trail (this was a nice part even!)
pic 3 is one of the washouts. you can see it destroying that side of the hill but look as it comes across the trail in front of the truck!
