Average operating temp

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Just an update... I installed my new Blue Hub fan clutch and temps have gone down consierably. I have 20k weight silicon diff oil waiting to be installed.

If you were to put in the 20k CST oil, would your fan now sound like a GM Vortec engine with the constant roaring sound and perhaps even loss in performance/mpg?

Just something to think about.
 
If you were to put in the 20k CST oil, would your fan now sound like a GM Vortec engine with the constant roaring sound and perhaps even loss in performance/mpg?

Just something to think about.

it sounds like that either when the engine is first started up or when the thermo sensor on the fan clutch senses the heat from the radiator fins.
 
If you were to put in the 20k CST oil, would your fan now sound like a GM Vortec engine with the constant roaring sound and perhaps even loss in performance/mpg?

Just something to think about.

FWIW -

Super Charged AZ guys run 24k on there blue hubs to keep cool

I'm non-SC running 17k on a [strike]black[/strike] Eaton hub with an opening temp of 125° with excellent results
 
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Just an update... I installed my new Blue Hub fan clutch and temps have gone down consierably. I have 20k weight silicon diff oil waiting to be installed.

This weekend I sat in the border traffic for 5 hours, wiht the AC on and Ultragage read 181F the entire time.

Highest temp I saw was 191 I believe after a long hard drive into stop and go driving. Which I think is a good temp. Next up is the 20k fluid.

Another thing I've been thinking about is that I dont really want the truck to be running TOO cool either... I feel 175-195 is a good operating temp.... any lower I dont think is actually good.

GB,

Sounds like you did a Baja run recently; hope you had a good time. Your 80 is now running very similar to mine with a new rad, tstat, and blue-fan clutch (with OEM oil). I rarely see above 191-195 with these new parts over the last year. I suspected you would have your recently reported "normal" results without changing the oil in your clutch, thus my earlier suggestion to try it first and report back. I agree with another herein, maybe shelve the CST oil for now and see how she works through the summer (though that suggestion puts me in the minority here).

I had a 60 whose fan ran all the time until I replaced the failed clutch. I felt the parasitic load of the constant fan when not needed was a waste of power/mpg. Since my 80's cooling system has been able to effectively keep up with anything I have thrown at it in the last year, I similarly feel that modding my clutch would be overkill (and potentially a waste). If I see a situation where the temps rise even close to scary temps, I will reconsider.
Saludos, J
 
Yes I sure did! Its funny cause I actually have my SENTRI pass, so I usually don't have to sit in that darn line very long, but of course I had passengers w/o the pass, so I was outta luck. :) Annnddd... came back during Sunday night... Ahh!! It was a nightmare!

I am for now going to stick with the OEM 10k fluid...I'll have the 20k when/if I need to upgrade it I suppose.

I had read Landtank post about how he felt that the blue hubs were "weak" in comparison to the black hubs, and that 20k fluid would be the minimal he'd run in them. I thought that was interesting. Maybe it was an old post.
 
So isn't it it that when the coolant temp reaches 205 the tsat is open all the way? I thought it opens at 195 (or is it 185?). So does the fan clutch actually keeps it cooler and won't let the tstat open at all or to a minimal (is that a good thing)? Aren't you running a bit cold if you are below 185?

A little off topic here, I've been trying out a 16" electric fan for about three weeks now (took off the fan clutch, more info on my other thread). Today was 88 degrees in the afternoon, felt like 90+ and in the stop and go traffic with AC on, it held coolant temperature at solid 199.4 (scan gauge). When I started moving past 20mph, the temp dropped to 180 gradually. It's a 35 miles long stop n go traffic, summer time gets pretty brutal sometimes, some day it takes upto 2 hours. I have set up the controller such that the fan kicks in at 205 and shuts off around 196/195 without AC. I thought the tstat doesn't open till 195. It's been working pretty good so far, I have been seeing temperature going up and down in my daily commute. Fan stays off at all time in highway driving. Also been tinkering with several high and low temp adjustment points.

Anyway, isn't the normal operating coolant temperate is between 195 - 205? Or I might be running too hot?
 
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Raid, that was my initial post, mentioning I was at 200F.

Id love to know what the normal operating temp range is on these motors. It seemed from the posts in this thread that the average is somewhere around 180F though. After doing the fan clutch, I would say my average temp is now @ 180F...

The fact that I have a newish OEM Radiator, new OEM Thermostat, new OEM Fan clutch, and have new coolant, Id say thats what the Toyota engineers wanted the temperature to be at, (at least for 70F atmospheric temps). I believe that you can be running at 215F and be fine.

However thinking of thermal expansion differences between the aluminum head and cast block, the hotter they get, the more internal stresses, and more prone to damage head gasket...? Sounds logical, not sure if thats true.
 
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I'm non-SC, running 17k in an Eaton clutch with an opening temp of 125° with excellent results

Fixed it for you!:hillbilly:

In my experience, all of the clutch types differ, require different viscosity fluid to have about the same level of performance. The Black hub is the most powerful, run ~10-12.5K in them. The Eaton is somewhat less, so run ~15-17K in them. The blue hub is the weakest, run 20-30K in them. This makes them preform about on par, work well in a desert climate. That said, they all have differing characteristics, valve stages, shearing area, etc, so it's difficult to directly compare them, other than long term delivered performance, what works for the need.

All of the factory type clutches work well or can be made to work well. They are very good quality, very durable. I have yet to see an aftermarket clutch that I would run in my rig, IMHO, all that I have had apart, are junk. But I run in the desert, so the best cooling performance possible is likely more important to me than most?
 
If you were to put in the 20k CST oil, would your fan now sound like a GM Vortec engine with the constant roaring sound and perhaps even loss in performance/mpg?

Just something to think about.

If it does that, something was done wrong, like the valve set too cold or too much fluid. They shouldn't be "on" at a high level constantly or even often. All of the valves are progressive, so should only run at the level needed, most of the time at a very low level.
 
If it does that, something was done wrong, like the valve set too cold or too much fluid. They shouldn't be "on" at a high level constantly or even often. All of the valves are progressive, so should only run at the level needed, most of the time at a very low level.

Thanks Tools R Us. This is good to know. I was thinking the mod to the "heavier" CST oil would make the fan clutch come on harder and sooner. If it does not come on sooner (i.e. relatively lower temps than a stock clutch), then it should not be wasting significant parasitic load spinning the fan (like I thought it would, per my post above).

It should be noted that Greenbomber and I live in San Diego County and travel in Baja. I think Tools R Us sees significantly higher temps in AZ than we do almost all the time.

I thought I read somewhere that the OEM tstat is just opening at 179-180 deg F. I forgot at what temp it is fully open. In line with this, I remember 180 being the design ideal/normal temp for the engine. Please correct me if I have this wrong.

Like Greenbomber, my 80 goes right to 180 and hovers there unless pushed hard where it will get into 190 to 198 range (e.g., towing uphill). I have very very rarely seen 200 deg. F or more in that last year.
 
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I thought I read somewhere that the OEM tstat is just opening at 179-180 deg F. I forgot at what temp it is fully open. In line with this, I remember 180 being the design ideal/normal temp for the engine. Please correct me if I have this wrong.
...

Kinda, sorta, maybe, how long is a piece of string?:hillbilly:

First opening is ~180F, starts opening and closing the bypass, fully open and bypass fully closed is ~200F. So it is still allowable to be bypassing coolant around the radiator at ~200F? Tells me that they were not serious about cooling until at least 200F at coolant intake.

The thermostat is in the coolant intake, so controls the temp of the coolant entering the motor from the radiator. From there it travels through and picks up heat from the block, oil cooler, head, etc, on it's way to the temp sensor near the upper water neck in the head. How much heat depends on motor load, etc, but if the thermostat is fully open, full cooling is needed, the sensor reading is going to be over 200F, more like 210F.

Many believe that the cooler a motor runs the better, NOT true. The hotter it runs, the cleaner and more efficiently it will run. At one time, 180F was the magic number, this was largely due to the oil available, it would start breaking down around 200F. Now, the cheapest oils are good for ~250F+.

If you want to win the "my motor runs cooler than yours" contest, simply switch to the S/C 170F thermostat. It will run cooler when not stressed, will burn more gas, make less power, build much more carbon in the intake, head, sludge in the valve cover, etc.

When doing big mountain passes, I don't even back off of the throttle unless I see over 210F. Consider that normal for a motor running at 100% output. That is likely conservative, Toyota doesn't do anything till 228F and then only turn off the A/C. Around there is also where the stock temp gauge starts to move out of the "dead" normal operation zone towards the red.

Lots of newer motors are being designed to run hotter, like up to 240F. New tech allows for higher coolant pressures, newer oils withstand it, etc, makes for more powerful/efficient/cleaner motors.
 
Kinda, sorta, maybe, how long is a piece of string?:hillbilly:

First opening is ~180F, starts opening and closing the bypass, fully open and bypass fully closed is ~200F. So it is still allowable to be bypassing coolant around the radiator at ~200F? Tells me that they were not serious about cooling until at least 200F at coolant intake.

The thermostat is in the coolant intake, so controls the temp of the coolant entering the motor from the radiator. From there it travels through and picks up heat from the block, oil cooler, head, etc, on it's way to the temp sensor near the upper water neck in the head. How much heat depends on motor load, etc, but if the thermostat is fully open, full cooling is needed, the sensor reading is going to be over 200F, more like 210F.

Many believe that the cooler a motor runs the better, NOT true. The hotter it runs, the cleaner and more efficiently it will run. At one time, 180F was the magic number, this was largely due to the oil available, it would start breaking down around 200F. Now, the cheapest oils are good for ~250F+.

If you want to win the "my motor runs cooler than yours" contest, simply switch to the S/C 170F thermostat. It will run cooler when not stressed, will burn more gas, make less power, build much more carbon in the intake, head, sludge in the valve cover, etc.

When doing big mountain passes, I don't even back off of the throttle unless I see over 210F. Consider that normal for a motor running at 100% output. That is likely conservative, Toyota doesn't do anything till 228F and then only turn off the A/C. Around there is also where the stock temp gauge starts to move out of the "dead" normal operation zone towards the red.

Lots of newer motors are being designed to run hotter, like up to 240F. New tech allows for higher coolant pressures, newer oils withstand it, etc, makes for more powerful/efficient/cleaner motors.

Thanks Kevin,

This is helpful to me. I know I do not want the motor to run too cool, but without this info I would otherwise back off the throttle if I was seeing 205 deg. F. or more on the scangauge.
 
This kind of gave me idea of the temperature range.

Also this link is another point of reference

http://www.expeditionportal.com/for...ature-on-an-80-Series-FZJ80-Landcruiser/page3

tstat.webp
 
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I'm doing a write up on my electric fan install and I'm glad to see my temps are in tolerance with a lot of the fan clutch folks in this post.

Here is the post - https://forum.ih8mud.com/showpost.php?p=9033241&postcount=35

In this post my average temp was 187f based on 2600+ measurements over 210+ Miles, but read the post it has some more detail. I can't wait for the summer time to see how well it preforms in the AZ Heat!
 
We are running ~155* on 80-90* days with a fixed a fan clutch. Looking to replace the fan clutch with a black hub. Is there an Aisin part number for that?
 
I'm doing a write up on my electric fan install and I'm glad to see my temps are in tolerance with a lot of the fan clutch folks in this post.

Here is the post - https://forum.ih8mud.com/showpost.php?p=9033241&postcount=35

In this post my average temp was 187f based on 2600+ measurements over 210+ Miles, but read the post it has some more detail. I can't wait for the summer time to see how well it preforms in the AZ Heat!

Thanks for keeping data of your temps:clap: I look forward to the Arizona summer reports, the real test for any cooling system.
 
Another data point, I have the green hub running 10k cst fluid with a 180 F thermostat in my 3fe fj80 and my running temps right now in AZ are 184 ish but it's winter so I'll report back when it warms up. Engine temp. was 194 ish with the stock thermostat so 10 degrees cooler right now. I'm happy I changed the thermostat since I live in AZ.
 
Hello,

I am pretty new but it seems like my FZJ 80 runs pretty hot. I live in MN and it is getting warmer here (summer time) but seems like with ac on full at idle it will get in the 200S. Cooling system is in great shape. Was wondering if Copper/brass core radiator will help? maybe oil cooler?
 

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