Running hot and out of ideas.... (2 Viewers)
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I mean you’ve been here long enough. This discussion comes up every 2-4 months and it’s always the same answers and has been for 20+ years.
Scientifically, it seems proven that for weight-to-heat displacement ratio, aluminum does better in almost every instance. Not going to argue this. And Toyota can say they are saving weight in every vehicle across a fleet. This is important as well due to gas mileage specifications. All auto manufacture is about weight savings for fuel economy. That’s the truth.
But these are systems; no one component is singular or designed outside of an overall systematic design for overall performance.
Personally—and I am not speaking for anyone here, nor am I an engineer, or a fluid dynamics professional, or a material scientist—I like that I can fix a brass radiator in the field with some epoxy. That’s valuable to me. I can’t do that with aluminum.
Ironically, I fixed my radiator with some epoxy in the middle of nowhere Utard with the OP @alvarorb many years ago… 2008? IIRC.
In a knarly sandstorm…. There he is in all his bigness!!
(Damn, I was fũcking 33 in this picture; I’ll be 50 in January).
Thanks to @TrickyT
Those were the good ol' days, for sure! And yeah, it keeps coming up 'cause definitely solid brass is cheaper than solid aluminum. I, like most don't like or want the plastic tanks for fragility reasons and why I, back around 2010 went with the CSF all brass. But I kept adding mods and weight and larger tires, like others and when the dog days of summer came around I wanted to run the A/C. Then is when it's most needed, but with my modded temp gauge, when I turned the A/C on, the engine temp climbed uncomfortably on hills or the highway. After tuning the fan clutch and cooling system with little to no results, what fixed my '94 - that came OEM with a brass radiator - was the cheap TYC aluminum. Tools and the AZ crew suggested giving it a try and I'm so glad I did. Since installing the TYC, I can run the A/C any damn time I want - like before I started messing with things. Another thing they mentioned was that with the price of the TYC, it could be considered a consumable. Except, it's not trail fixable - unless you carry a spare......I mean you’ve been here long enough. This discussion comes up every 2-4 months and it’s always the same answers and has been for 20+ years.
Scientifically, it seems proven that for weight-to-heat displacement ratio, aluminum does better in almost every instance. Not going to argue this. And Toyota can say they are saving weight in every vehicle across a fleet. This is important as well due to gas mileage specifications. All auto manufacture is about weight savings for fuel economy. That’s the truth.
But these are systems; no one component is singular or designed outside of an overall systematic design for overall performance.
Personally—and I am not speaking for anyone here, nor am I an engineer, or a fluid dynamics professional, or a material scientist—I like that I can fix a brass radiator in the field with some epoxy. That’s valuable to me. I can’t do that with aluminum.
Ironically, I fixed my radiator with some epoxy in the middle of nowhere Utard with the OP @alvarorb many years ago… 2008? IIRC.
In a knarly sandstorm…. There he is in all his bigness!!
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View attachment 3674807
Thanks to @TrickyT
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Please read post #23 in this thread.
Jon, I read your post #23 back on 6/25 after you posted it. I agreed with it back then, but just noticed what is highlighted above, but missed that before. So, you're saying that you're getting better performance from a brass OBD I radiator than you were getting from the OEM aluminum radiator that should have been originally in your 1997 LX450? Is this experience talking or what? All things being equal, the reason I'm asking is, it goes against the research I've done here on Mud, the net and my experience with brass and aluminum. BTW, I agree that the other points you mentioned in your 6/25 post are critical for proper cooling system performance.
I can't really say one way or the other. About a month after I brought my LX450 home from Phoenix (2013), the original radiator developed a crack in the top tank, so it needed replacement ASAP as it is my daly driver. This was also before I had my Ultragauge, so I have no data to back up my statement regarding "better cooling capacity".
At the time, I called Onur and he expressed out a new OBD1 FZJ80 unit, while I picked up all new hardware.
He told me that it cools better, and I had no reason to doubt him. The unit has been flawless for however long it has been installed, but again, no real world data to back that up. Perhaps I should delete that statement in my post.
mudgudgeon
Resident galah
Do some googling on thermal conductivity of various metals.
Copper has a very high thermal conductivity. It absorbs heatfastt, and sheds it fast
Aluminium Is also highly conductive, but not as good as copper.
Aluminum absorbs heat more slowly, and is slower to shed heat.
Brass has the lowest conductivity of these three.
All things being equal, copper seems better.
The properties of aluminium mean the coolant tubes in cores can be made thinner, flatter, wider. So you have a greater surface area in contact with air flow, and less metal to hold the heat.
Same with cooling fins. They are thinner, so shed heat faster than thicker copper fins.
Aliminum cores will be lighter (not that this matters a lot for a landcruiser).
One downfall of brass/copper radiators is the different thermal expansion rate with brass and copper. This can crack soldered joints.
Thanks for your info and subjects to study! All I can relate is what I experienced. I had virtually a new all copper/brass CSF (less than 1 yr old, well maintained), recent Landtank modified blue fan clutch, 50/50 coolant, OEM thermostat and radiator cap, radiator installed with foam to seal to frame and shroud that couldn't run A/C without coolant temps exceeding 200F under load with ambient air temps 95F+. Next thing done was install a TYC aluminum radiator and bingo - literally - the cooling system was a winner. Coolant temps remain 190F or less with A/C running and 95+ air temps at any speed. Granted, my '94 weighs 7200 lbs +, running 35" tires and I tow an off road trailer. So I need to keep revs up above 2K+ to let the fan clutch do it's job under load and warmer temps. I'll also engage low range quicker to help keep revs up and take the load off the engine off road. I've got the CDL switch and pin 7 mod, so I don't worry about drive train bind.
alvarorb
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Tom, my experience has been the opposite with the Koyorad aluminum radiator vs. the brass. Having said that, I used a OEM aluminum radiator for over 15 years with no issues whatsoever. With the stock fan clutch and no mods.
Regards
Alvaro
Interesting! I found out after I installed the TYC that it's fin design was different than the Koyo aluminum radiators and out performed them in the 80's that the Copper State Cruisers were running. One thing's for sure, our 80 series cooling system is a "tangled web" to keep balanced and has very little room for error. Thank God for this forum, though! It's sure helped me!
mudgudgeon
Resident galah
I don't really agree with this. An accumulation of errors is the problem.
80 series were THE GO TO for farmers, horsey people, boat people, caravan toting older people in Australia for a long time.
They are more than up to the task of towing trailers, boats, horses, caravans etc all over Australia including the hottest parts of the country.
No one got in their new 80 and said, can't tow this huge boat to Broome without a scan gauge.
What we have here is a failure to mitigate. ( bonus points if you get that reference
)We have 30 year old vehicles with some critical parts of the cooling system that are readily overlooked.
Radiators clog up, internally and externally.
Thermostats become ineffective.
Fan clutches lose their grip.
Radiator caps lose performance.
Lots of these things appear normal, and don't have obvious signs of failure, even when they do fail.
We add heavy accessories, large tires and stuff that increases drag. All of which adds to the demand on engines and cooling
Engines deteriorate and are worked harder to achieve the same output. We are impatient and expect 30 year old technology to perform the same as modern cars, so we push the 80s hard.
I really think its just a case of maintenance is needed of all the parts of a system with appropriate parts to maintain the original capabilities.
When you swap out OEM parts, you roll the dice on whether aftermarket parts are equivelant. Hard to know coz so often we rely on subjective anecdotal experience of other enthusiasts.
I have been dealing with the cooling issues on my 80s on and off for 6-7 yrs now. My issues were not your typical running hot idling or cruising @ 75mph, but issues when the rig is under extreme heat or extreme load during offroading or climbing steep gradse @ 110F heat close to 7k curb weight with oversize tires, etc. Although i had a case where i replaced my blown factory OEM unit with a CSF brass/copper and immediately running 215F crusing @ 70mph . Yanked the unit out after a month and went with all alum. unit going forward. The results were apparent. The all alum. unit runs a good 10-15F cooler in the same controlled environment - 190 F cruising - perfect right? Well, it is good enough for a daily driver or commuter/mall crawler, but not good enough for offroading in 90-100F heat. I get 220F temp all day off payment when i don't get enough air flow thru the front when i am on 4Lo. Added 15k oil in the clutch fan and timed it open sooner @ 190 seems to do the trick when i can rely on high rpms to cool the engine. That worked well for a few years with the addition of hood vents, dual elec. pusher fans on front of heater core, etc. I won't go into details of why i made the switch to full elec. fans recently, but i can tell you my modded 20k oil fan clutch with foams pulls more air than my new PWM controller elec. fans rated @ 40000 cfm. I still see 220F pulling steep grade up 8k elevations @ 110F heat with the new setup during my most recent trip to Montana. I might explore 5-6k range CFM puller fans in the near future, but there are definitely pros and cons to both. For your normal 80s with 35s and a basic lift - Overland type rigs, i would recommend a 15k oil upgrade to the factory fan clutch with a good OEM style radiator with a good sealed fan shroud would be the ticket.
Having run both brass and AL, here's my take. Sure the possibility of a trail repair is a factor in favor of running brass That would be one bad hot day out of a bunch if you're running AL. But running brass means every hot day is at least a partially bad day for most of us.
Something else to consider is that the extra heat you'll likely have from running brass has some effect on everything else under the hood. Sure, it's hard to specify or quantify, but there's no denying it's a net negative of running brass.
Something else to consider is that the extra heat you'll likely have from running brass has some effect on everything else under the hood. Sure, it's hard to specify or quantify, but there's no denying it's a net negative of running brass.
I had always heard that aluminum was an upgrade vs copper/brass. There's definitely something to be said for the field repair factor, but I had always heard that the design of aluminum cores made them far superior. I'm not about to tell mudders that they're wrong about their lived experience, so I suspect that "far superior" may be mostly marketing fluff. Lighter, certainly. I suspect we'd have to directly compare A to B to find out, but that leads directly to the point @mudgudgeon made: if everything else is running perfectly, the 80 cools just fine. You guys with turbos and superchargers have a bit more load on your system, but my stock engine cools extremely well with a newer AL rad, and a blue clutch fan with 10k oil opening at 105F. I actually switched out the 15k oil because it was noticeably hurting mileage and I was hearing it roar when my OBDII gauge said I was running at 185F.
My point, almost exactly. No one is now buying a new 80 anywhere, especially here in the USA. So consequentially new 80 owners are, as you say, dealing with 30 yr old vehicles and their "excess baggage". With the 1FZ engine, cooling system performance is high priority, if you want the rig to be reliable. If it's been neglected, and almost always they are, it will be a job to get it back to where it should be.I don't really agree with this. An accumulation of errors is the problem.
80 series were THE GO TO for farmers, horsey people, boat people, caravan toting older people in Australia for a long time.
They are more than up to the task of towing trailers, boats, horses, caravans etc all over Australia including the hottest parts of the country.
No one got in their new 80 and said, can't tow this huge boat to Broome without a scan gauge.
What we have here is a failure to mitigate. ( bonus points if you get that reference
We have 30 year old vehicles with some critical parts of the cooling system that are readily overlooked.
Radiators clog up, internally and externally.
Thermostats become ineffective.
Fan clutches lose their grip.
Radiator caps lose performance.
Lots of these things appear normal, and don't have obvious signs of failure, even when they do fail.
We add heavy accessories, large tires and stuff that increases drag. All of which adds to the demand on engines and cooling
Engines deteriorate and are worked harder to achieve the same output. We are impatient and expect 30 year old technology to perform the same as modern cars, so we push the 80s hard.
I really think its just a case of maintenance is needed of all the parts of a system with appropriate parts to maintain the original capabilities.
When you swap out OEM parts, you roll the dice on whether aftermarket parts are equivelant. Hard to know coz so often we rely on subjective anecdotal experience of other enthusiasts.
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mudgudgeon
Resident galah
What do you routinely carry on trail rides that lets you patch a brass radiator?
Personally, nothing. Note I mentioned the "possibility" of a field repair. In practical terms, the only time for most of us when this would become a factor is in the purchase decision phase. Then nothing else is done about it. If I was going to the boonies, solder, flux and a torch, I suppose. My thinking is more along the lines that local talent and resources could be called upon to repair. In this age where overnight freight is available virtually everywhere, getting a new radiator is a far differrent proposition than when these tgrucks were built 30 years ago.
mudgudgeon
Resident galah
Agreed, at time of purchase, the idea of one being more field repairable than the other gives a false sense of security.
The reality of succesfully soldering a brass radiator in the boonies is slim.
Very hard to solder contaminated brass with or without flux. And getting it dry and water free so steam doesn't blow holes in your solder joint is gonna be difficult. If the leak is a damaged tube in the centre of the core, access is difficult too, let alone soldering up a hole in amongst fins.
I once epoxy puttied my 105 series radiator. I was broke, and my daily driver was leaking bad. I stuffed epoxy putty into the fins around the leak site and was able to stuff enough in to reduce the leak to a a small drip.
I ran this repair for a couple of months doing 150-200 km daily.
Ran it without radiator cap so the system wasn't pressurised. I had to top up the coolant every day, but I had no issues with cooling until i had funds to replace the radiator.
Ingenuity - Well done! What we'll do to get through the day or from point A to B fills volumns...lol. I was in my 20's and had a '72 Datsun (now Nissan) pkup and was on a trip out in the middle of Nowhere, North Dakota and had been fiddling with the timing which I thought was randomly changing on me. Anyway, I over tightened the bolt and it broke off.
I didn't have many tools, but I did have a pair of Vice Grips, so I used them to secure the dizzy until I could reach a hardware store. This was back in the '70s and metric bolts in the midwest (USA) were scarce, if at all to be found. I eventually had to continue to a Dealer, which at the time, was even harder to find. Luckily, dealer had the part because, I guess, I was not the 1st idiot that did this....
from my reading while copper transfer more effectively that aluminum the lead solder doesn't. So the overall performance of a copper radiator is greatly influenced by the quality of how it's made.
My personal experience with a an OEM copper radiator was rather dismal. Not from a cooling standpoint but from a longevity one. What ever TF we lay down on our roads in winter ATE the fins in the radiator in just 3 years. I was overheating a little and figured it was mud in the radiator and took a hose to it. In the center air flow area there was nothing but rods. Nothing but aluminum for me now.
My personal experience with a an OEM copper radiator was rather dismal. Not from a cooling standpoint but from a longevity one. What ever TF we lay down on our roads in winter ATE the fins in the radiator in just 3 years. I was overheating a little and figured it was mud in the radiator and took a hose to it. In the center air flow area there was nothing but rods. Nothing but aluminum for me now.
