LJ78 Big Fan Upgrade #2

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We definitely need to figure out what Toyota part number is for the 17.5" fan with swept blades. I'll look into it again and see if I can come up with anything.
 
That would be awesome! I live in Arizona so anything I can do to keep this engine cool I’m all for! I’ve done some research but have come up empty handed. Hoping you can find the correct part number for the fan!
 
That would be awesome! I live in Arizona so anything I can do to keep this engine cool I’m all for! I’ve done some research but have come up empty handed. Hoping you can find the correct part number for the fan!

Most important thing is to change the viscous clutch fan silicone oil. Also, I've run both a 56mm and 48mm thick radiator core in my LJ78. The 56mm core cools WAY better than the 48mm. Huge difference. The fan makes a big difference too for sure.
 
I switched the clutch fan silicone to a 15,000 cst and adjusted it to start opening at 95 degrees per the blue fan clutch mod instructions. Took about 45 mil. What is the part number for the bigger radiator? I have lots of questions. Very new to this little 2lte.
 
I switched the clutch fan silicone to a 15,000 cst and adjusted it to start opening at 95 degrees per the blue fan clutch mod instructions. Took about 45 mil. What is the part number for the bigger radiator? I have lots of questions. Very new to this little 2lte.

I think the bigger radiator is just a larger than OEM re-core. 48mm is OEM.
 
Awesome! I’ll check into that. Find anything on the fan or am I sol and stuck with the stock one? I’ve been cleaning up the engine bay getting rid of a lot of hack job wiring making everything nice and tidy again. I noticed the boost gauge line goes directly to the pig port on the bottom of the throttle body. Looking at other engines online, they all seem to have a t fitting that goes to a solenoid and some weird canister that is mounted to the throttle body. Any insight on what that is?
 
Find anything on the fan or am I sol and stuck with the stock one?

Looking into it more, I found another fan part number that should work well. It's the fan from an HJ60 or HJ61. It doesn't have swept blades, but it does have eight, and it is the right diameter and offset. I have actually heard of someone using a 2H fan on the 2LTE with no problems before. Might even fit better than the swept fan in fact, as I don't think they had to modify the fan shroud at the top. The part number is: 16361-68010
 
So I drove my 78 too and from work today. It’s the first time it’s seen a Arizona hot afternoon and I had to shut the a/c off and baby it to keep it from overheating. Fan clutch oil replaced with 15,000 cst and set to open at 95 degrees. Has Evans coolant in it with 3L new head. Will the big fan keep me cool??
 
You’ve tackled a few of many projects the 2 Lte crowd has done. There are several others as you can read about in the build threads. Have you enlarged your exhaust? 2 1/2 does help. An intercooler does wonders and there are several different designs in those threads. Another would be having your rad recored with higher quality product. And of course the fan It’s deffintly a process for all of us. But you face a greater obstacle than most of us living in AZ.
 
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One of the most dramatic things I did to control temps was swap to the high flow thermostat. I was easily jumping over 205F and I would have to baby it to keep it from going higher prior and since that swap the highest I have seen was 194F. So much modification has been done to my truck that changes are somewhat hard to pin down to any one thing, but the high flow tstat was easily recognizable. I also noticed a dramatic increase in how quickly the temp drops back down. If I am on the freeway and it is running 192-94F and I get off the freeway, within just a few moments, I am back down in the 180's. Before it took a while to cool down because the water exchange was too slow due to the smaller opening range of the stock tstat.
This is the info on it. You can usually find them on Ebay.
TT2322-192 - Thermostat | Tridon

The larger fan will definitely help your temps at slower speeds such as in town or traffic. It won't really have any affect at highway speeds.
 
Upgrading the exhaust to 2.5 is the plan downthe road. I think I’ll upgrade the fan and thermostat you recommended and go from there!
 
Hey guys, so driving the lj to and from work this week. It’s been 90-100 degree Fahrenheit out. Just cruising under minimal load with ac on it seems to do good but as soon I start climbing hills I have to shut the ac off. It climbs to 3/4 the way up on the temp gauge. If I let off and cruise under low load it cools right down. I went ahead and orderd the high flow thermostat. Waiting for it to arrive. I’m thinking the factory thermostat is just not letting coolant flow fast enough. Since I rebuilt the fanclutch it moves a lot of air. What are your thoughts?
 
+1 on that advice. Do not trust the factory gauge. It will just lead to heartache.
The factory tstat does not open as far or as fast as the Tridon. Opening diameter is pretty close to the same. It will make a huge difference for you in keeping the water temps under control.

I didn't see if you had mentioned it, but, do you have and EGT gauge? Water and EGT gauge are pretty much mandatory on these engines . They run down right scary EGTs from the factory.
 
I have one, just waiting to tap the thermostat housing when I replace the thermostat. I’m just curious if people think the high flow thermostat is going to fix this issue.
 

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