I can't seem to find anyone selling a radiator with more than 4 rows... I'm wondering why? My 3B with a turbo puts a lot of heat into the loop, the stock rad is already 4 row but I want to upgrade it.
Why no radiators larger than 4 row? (1 Viewer)
- Thread starter amaurer
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LMGTFY:
https://www.google.com/#hl=en&sclie...cd17f&biw=1402&bih=753]Google: 5 row radiator
Why not just add a big thermostatic fan to the front?
https://www.google.com/#hl=en&sclie...cd17f&biw=1402&bih=753]Google: 5 row radiator
Why not just add a big thermostatic fan to the front?
- Thread starter
- #3
Well fxxx, I was googling for 6 row and got zip.
Its already got a big fixed fan and a good shroud, etc etc. The problem is overheating at highway speeds, its just fine at idle - I think I'm just topped out for the rad, I can't imagine any more airflow is the issue.
Its already got a big fixed fan and a good shroud, etc etc. The problem is overheating at highway speeds, its just fine at idle - I think I'm just topped out for the rad, I can't imagine any more airflow is the issue.
JohnnyC
Long ago TLCA# 2231
Are you saying you have a solid fan? I would think you would need a clutch fan... The solid fan is probably restricting airflow
My 2c
My 2c
Bigger oil cooler?
Mark W
Yep, it's true. I just don't care that much.
I would look into where the heat is coming from. Depending on your setup, you may not have enough air getting in to burn the fuel efficiently. This will lead to hot exhaust, hot turbo, heated intake charge, higher engine operating temps..
You may need an intercooler. less restrictive intake plumbing or a less restrictive exhaust system.
OR... you may need to flush your radiator if it is old and possibly clogged. A good four core Cruiser rad should have no problem cooling a properly running 3B w/turbo.
If you are running a clutch fan (best choice) make sure the clutch is working correctly. A bad fan clutch can cause overheating at highway speeds too. I ran in circles for a while a few years back installing brand new aftermarket fan clutches that were not locking up soon enough or hard enough. Installed OEM fan clutches in the two rigs i was fighting with and solved the problem.
This is Ratpuke's old Rig that you are dealing with, yes?
In answer to you original question. More than 4 rows start loosing effectiveness. and size can be a problem too.
A more modern aftermarket cross flow radiator made of AL will cool better (AL is not as good for heat transfer, but the cross flow design is better).
Mark...
You may need an intercooler. less restrictive intake plumbing or a less restrictive exhaust system.
OR... you may need to flush your radiator if it is old and possibly clogged. A good four core Cruiser rad should have no problem cooling a properly running 3B w/turbo.
If you are running a clutch fan (best choice) make sure the clutch is working correctly. A bad fan clutch can cause overheating at highway speeds too. I ran in circles for a while a few years back installing brand new aftermarket fan clutches that were not locking up soon enough or hard enough. Installed OEM fan clutches in the two rigs i was fighting with and solved the problem.
This is Ratpuke's old Rig that you are dealing with, yes?
In answer to you original question. More than 4 rows start loosing effectiveness. and size can be a problem too.
A more modern aftermarket cross flow radiator made of AL will cool better (AL is not as good for heat transfer, but the cross flow design is better).
Mark...
Why not intercool? There are plenty of factory side intercoolers you could use,
I have seen this a couple of times before. Make sure the fan is not bolted on backwards. It will let air flow through the radiator at idle (backward, but airflow none the less) , but will keep air from flowing properly on the highway.
There are 5 core radiators. They are found on industrial stationary motors. They are not a true 5 row design. It is more of a three/two/three/two. I have one in my 40. Custom built by Hoffman Radiator in Orange Calif. You can forget about a heater. My V-8 sits a 185 no matter if its summer or winter. run all day in the mountains or desert, no change 185. and if its cold here in Idaho, 20* to 40 have to cover the rad to get any heat in cab.
- Thread starter
- #11
To be honest with you, its both my trucks which made me think its just a 3B thing. I have EGTs on both and never go over 1250F.
The BJ42 is on 31's with a turbo. The Tstat and rad are brand new (recore) about 2 years ago, new Tstat, fixed fan, etc. Fan direction is correct. Shroud is intact. Temps are 190 around town, but on the highway they start to creep, and after holding 55mph for 15 minutes it'll be up near 210F. If its below 50F outside then temps stay at 200F until I hit a hill. If its HOT out then I have to slow down or I'll be in trouble.
The BJ73 (Charla's) is on 33's with no turbo (this one has the rotary pump too). Tstat and fan clutch are new. Shroud intact. Original radiator though. It behaves very similarly; highway temps if trying to hold 65mph (it has a 5 speed) are about 207F. In town its 190F. I used to live on a 2000' grade starting from seal level. I'd generally take the hill at about 35mph to keep the EGTs below 1250F, but on a hot day (90F+) I have to slow to a crawl or I'd easily be over 225F by the top.
Do you have enough fuel? What are theEGTS?
I reckon a 4-core should be over-capacity Drew.
So I suspect your core is partially clogged with scale, rust shards, or whatever (from PO history).
(I'm assuming you keep your coolant clean and properly treated now.)
So I suspect your core is partially clogged with scale, rust shards, or whatever (from PO history).
(I'm assuming you keep your coolant clean and properly treated now.)
- Thread starter
- #14
I have pyros in both and keep EGTs under 1250. Plenty of fuel.
Tom at least one rad is brand new. What should concern you, given your anti-additional-gauge philosophy is that 220f only reads at halfway on the stock gauge.
(in the bj42... The 73 gauge claims a redline at about 220)
Tom at least one rad is brand new. What should concern you, given your anti-additional-gauge philosophy is that 220f only reads at halfway on the stock gauge.
(in the bj42... The 73 gauge claims a redline at about 220)
5 row cores don't necessarily cool better the three or even two. Two 1" tubes cool better than five 3/8"
tubes. Most radiators are built on a stock core width. Only so many tubes of a giver dimension will fit in a particular core width. Most three row land cruiser cores have three 1/2" tubes and 4 row versions use four 3/8" tubes. The surface area of the two tube configurations is nearly identical so the heat dissipation probably won't vary much between the two. There are "heavy duty" vs "standard duty", the heavy duty have more fins per inch and closer spacing between the tubes so more rows of tube fit in a particular core.
Aluminum Radiator mfg's such as Griffin, Howe or Ron Davis can build a radiator with either 1" or 1 1/4"
cores. The surface area of two 1" cores is a little over 6% better than four 3/8' cores where the two
1 1/4" cores would give you about 33% more tube surface.
tubes. Most radiators are built on a stock core width. Only so many tubes of a giver dimension will fit in a particular core width. Most three row land cruiser cores have three 1/2" tubes and 4 row versions use four 3/8" tubes. The surface area of the two tube configurations is nearly identical so the heat dissipation probably won't vary much between the two. There are "heavy duty" vs "standard duty", the heavy duty have more fins per inch and closer spacing between the tubes so more rows of tube fit in a particular core.
Aluminum Radiator mfg's such as Griffin, Howe or Ron Davis can build a radiator with either 1" or 1 1/4"
cores. The surface area of two 1" cores is a little over 6% better than four 3/8' cores where the two
1 1/4" cores would give you about 33% more tube surface.
..Tom at least one rad is brand new. What should concern you, given your anti-additional-gauge philosophy is that 220f only reads at halfway on the stock gauge.
My OEM gauge has never risen beyond 1/3 so I guess that would be one reason why I've never risked boiling my coolant (with my original cap that won't pressurise my coolant system and that I persist in running for nostalgia's sake).
And before YOU say it, I accept that my 1B has a lower power output than almost any other engine anyone on ih8mud runs.. So that's another reason.
Even so, I am surprised by your "1/2 scale = 220 oF".
Where did you get that from?
And I don't recall seeing many BJ42 owners (turbo or non-turbo) complaining that their stock radiator isn't up to the job. As I recall, that complaint usually comes from the V8-transplant folk. (BJ42turbo is one that I've found though.)
I'm more likely to find comments like this (and from very much respected people):
(pulled from this thread: https://forum.ih8mud.com/70-series-tech/39717-75-series-4-core-rad-bj70.html#post434151)
(Wish you guys would talk sensible Centigrade values. Lucky I'm an old bastard so I can still recall
Fahrenheit!..
)
Mark W
Yep, it's true. I just don't care that much.
I am not all that familiar with the specifics of Toyota Diesels, but if you are running at a continuous 1250 EGT, that seems damn hot to me. I *think* you are not saying that however, ust tht you are seeing that for peak EGTS.
And your comment about plenty of fuel catches my eye... High EGTs are associated with too much fuel, not too little.
Based on that... and again, NOT being a real "Toyota Diesel Guy" (Spending my diesel time with older American powerplants more)... I would say, make sure yu injection pump is advanced enough, and if it is, then look at turning your fuel down some, keep your extended duration EGTs under 1100 or so and see what that does to your cooling issues.
Mark...
And your comment about plenty of fuel catches my eye... High EGTs are associated with too much fuel, not too little.
Based on that... and again, NOT being a real "Toyota Diesel Guy" (Spending my diesel time with older American powerplants more)... I would say, make sure yu injection pump is advanced enough, and if it is, then look at turning your fuel down some, keep your extended duration EGTs under 1100 or so and see what that does to your cooling issues.
Mark...
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- Thread starter
- #18
Most people don't have a second temperature gauge installed to compare REAL values. Both of my trucks do, however.
Well the conversion data you've gathering in your real-world experience doesn't agree with this Drew:
when you take into account that my thermostat is supposed to begin opening at 82oC and be wide-open at 95oC.
So from my t/stat specs, I believe Toyota must consider temperatures over 95 oC (203 oF) as entering the "overheating" range.
(So I'm going to ignore your real-world stuff once again and retreat once again into my peaceful stress-free semi-vegetative delusionary state.
)
If the 40 series is either bit like the 60 series then the factory gauges suck. My bj62, before the rad was replaced, would hit 240 on the after market mechanical gauge climbing big hills when towing my Whaler and the factory gauge would not even be in the red.
This is why I am considering an aftermarket gauge set for the bj40.
On another note, I assume the lower mark on the oil pressure gauge in the bj40 Is min oil px at idle?
Daryl
This is why I am considering an aftermarket gauge set for the bj40.
On another note, I assume the lower mark on the oil pressure gauge in the bj40 Is min oil px at idle?
Daryl
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