92 FJ80 Overheating Going Uphill

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Hey, I have a 92 FJ80 that is overheating after about 5 miles going uphill.. I don't have any issues off road, around town or "normal" freeway driving - only when engine is taxed heading uphill.. Have ~ 2yr old radiator and I just changed water pump, thermostat, and fan clutch.. Still overheating.. Stumped..
 
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Did you use OEM parts, with the exception of the radiator?
Is your fan shroud in place and tightly sealed to the radiator?
 

Squash

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What temps are you seeing?
You should avoid O/D or select 3rd gear to prevent the tranny from hunting for gears as this creates lots of heat.
Also experiment with keeping rpms up and avoid lugging and engine uphill.
 
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What temps are you seeing?
You should avoid O/D or select 3rd gear to prevent the tranny from hunting for gears as this creates lots of heat.
Also experiment with keeping rpms up and avoid lugging and engine uphill.
I am not sure exact temps.. Gauge is usually pegged just below horizontal, then it starts to move up and just keeps going until I pull over to let it cool down.. I do see a bit of an impact if I turn heater on (front and rear).. However, my front heater doesn't seem to work (blowing luke warm air).. Possible heater core problem or ?.. I don't know if the heater core could be impacting the overheat as well.. Yes, keep it in 3rd during steady climbs and try to keep rpms up to maintain any type of speed..
 
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I am not sure exact temps.. Gauge is usually pegged just below horizontal, then it starts to move up and just keeps going until I pull over to let it cool down.. I do see a bit of an impact if I turn heater on (front and rear).. However, my front heater doesn't seem to work (blowing luke warm air).. Possible heater core problem or ?.. I don't know if the heater core could be impacting the overheat as well.. Yes, keep it in 3rd during steady climbs and try to keep rpms up to maintain any type of speed..
The front heater core sounds plugged, frankly. That could also be plugging the newish radiator.

I'd gently backflush just the heater lines until they run clear. I'd then gently backflush the radiator until it flows clear as well. It's more involved, but wouldn't be a waste of time.
 
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fan clutch.....i run thicker oil in OEM clutch...also alum. radiator makes a huge diff. vs brass/copper. Mine used to run hot on hill climbs, replaced radiator, fan clutch, waterpump, thermostat, now the temp stays below 200F on hill climbs with full AC...
 
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The front heater core sounds plugged, frankly. That could also be plugging the newish radiator.

I'd gently backflush just the heater lines until they run clear. I'd then gently backflush the radiator until it flows clear as well. It's more involved, but wouldn't be a waste of time.
Thanks for the suggestion.. Will give it a go this weekend..
 
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Hey. Still looking for some help.. I back flushed the heater core (not plugged) and broke down and replaced the 2-3 year old radiator.. I am still seeing the problem with over heating while taxing the engine going up hill for about 4-5 miles.. I have basically replaced everything in the cooling system.. Also with the back flushed heater core not being the problem, the front heater still isn't working (rear heater is working). The heating control / blend door and heater fan seem to be working fine.. I am not sure if these two issues are related but I thought I would throw it all out there.. Is over heating a "common" issue with 92's? Appreciate all the feedback received thus far and any other suggestions..
 
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Hey. Still looking for some help.. I back flushed the heater core (not plugged) and broke down and replaced the 2-3 year old radiator.. I am still seeing the problem with over heating while taxing the engine going up hill for about 4-5 miles.. I have basically replaced everything in the cooling system.. Also with the back flushed heater core not being the problem, the front heater still isn't working (rear heater is working). The heating control / blend door and heater fan seem to be working fine.. I am not sure if these two issues are related but I thought I would throw it all out there.. Is over heating a "common" issue with 92's? Appreciate all the feedback received thus far and any other suggestions..
Did you replace with OEM, or go for aluminum?

The common thing on the 3FE is that the stock radiator isn't an overachiever, so airflow is key. Sealing the fan shroud to the radiator is needed to force airflow through it, not just near it.

If that's done, then you have the fan clutch to consider. Does it turn easily, with the engine cold, or stiff? Does it roar at startup?

That said... The front heater not working tells me something still isn't right in the cooling system. How certain are you the system has been fully bled of air?
 
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fan clutch.....i run thicker oil in OEM clutch...also alum. radiator makes a huge diff. vs brass/copper. Mine used to run hot on hill climbs, replaced radiator, fan clutch, waterpump, thermostat, now the temp stays below 200F on hill climbs with full AC...
Do you mind sharing which radiator and fan clutch etc you put in? Driving back from Moab right now and we def had this issue climbing the hills around there. AC stopped blowing cold after some of the climbs as well
 
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Do you mind sharing which radiator and fan clutch etc you put in? Driving back from Moab right now and we def had this issue climbing the hills around there. AC stopped blowing cold after some of the climbs as well
The proper fan clutch for the 3FE engine is the green/aqua hub Aisin FCT-049. You did not specify what engine you have.
 
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The proper fan clutch for the 3FE engine is the green/aqua hub Aisin FCT-049. You did not specify what engine you have.
Sorry. I have a lx450. 1fzfe. I haven’t pulled mine out just yet to see which it is. I suspect it’s original. Honestly I never let the engine get to the red. I pulled over a ton. It looks like I have the original Radiator. So I am trying to decide if I just drain the fan clutch and toss in some 10000 CDT silicone lubricant in there to see if that fixes it.

but after 7 days at Moab. This is just part of what I need to address. 😂😂
 
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Do you mind sharing which radiator and fan clutch etc you put in? Driving back from Moab right now and we def had this issue climbing the hills around there. AC stopped blowing cold after some of the climbs as well
I put in a Ron Davis Alum. 2 row, and a Aisin Green fan clutch with thicker 15k oil and adjusted timing to open...
 

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