97 FZJ80 + SC + Baja Heat = High Coolant Temperatures (1 Viewer)

[BajaCruiser94]

Current Form:
1997 FZJ80 - 40th Anniversary Edition
190K Miles
Head Rebuilt and Gasket done 500 miles ago with OEM parts.
Magnuson Supercharger Installed during head rebuild
Orange Hub Fan Clutch sourced thru LandTalk
Running Stock Non-Ringed Fan
Thermostat done 1 year, 1000 miles ago.
Radiator serviced 50 miles ago.
ProComp Aux Fan Installed
Original Shroud, with lower part damaged.
ARB Bumper, 305 BF MT's, Stock Gearing.

Some extra datapoints:
- Monitor tool; OBD2 ELM Bluetooth Adapter with DashCMD app in ipod.
- Before supercharger, no high coolant temperatures.
- Supercharger, stock fan clutch + 20K oil + Ringed Fan + cool weather, no high coolant temperatures.
- No difference observed by running the Aux Fan (expected).
- Orange Fan Clutch is a monster, huge amount of air is felt, audible roar is amazing.
- Max temperature observed has been 219, no AC cutoff yet
- AC Performance is excellent, even at 219.
- Baja Heat Max is around 125*; very dry heat; havent reached the max so far this year
- IAT are between 135 and 150*
- I can manage to lower temperatures by increasing idle speed while in neutral to 2000-2500 rpm's.
- Opening the hood and increasing idle reduces temperatures faster.
- Using boost on the streets significantly increases temps.
- Lower fan shroud got damaged by the ringed fan due to worn out engine mounts; mounts were replaced and shroud will be replaced next week.
- No catalytic converters.
- No coolant leaks.

Hard Data:

SC + RingedFan + Stock Clutch w/20K Fluid:
80C Weather - OffRoad Trails - 196-201.
90C Weather - Highway 196-207; Max was achieved using boost on a long incline; cooled down after.
Stop an Go traffic at town 205-215.
100+ Weather - No Data, didn't dare to drive it.

SC + StockFan + LandTalk Orange Hub Clutch
90+ Weather - Highway - 196-199
Stop and Go traffic at town 199-203
100+ Weather - Highway - 203-205; no inclines.
- Stop and Go traffic at town 208-219 (Max was reached at a stoplight)

While doing some tests on my driveway after arriving home from a small drive at night wih 90ish weather; temps were 199; then every two minutes or so it will creep up 2*; after 20 or so minutes idling with AC on, temperature reached 217, then I opened the hood, then temperatures came down to 215; increased the idle and I could get them down to 199 again.

So, Im not overheating yet, but Im in the limit; and I feel I shouldn't be; I've read guys in Phoenix with similar weather are always running below 200; so Im clearly missing something; and I dont want to start throwing money (more) at it randomly
The Radiator shop mentioned my rad didn't have significant sludge in it; just normal build up; no difference found before and after rad service.
Im ruling out the Clutch because its new, its sourced by LandTalk and the roar is obvious together with the AC outstanding performance.

Im achieving airflow, Im just not getting that airflow to cool the coolant, and its only on 100+ weather temps, even on the highway, I feel and observe temps not cool enough (sub 200*)

Hood vents are being installed on Monday; but I dont expect 10* difference with them.

Things that havent been replaced yet:
- Water Pump
- Radiator (Serviced already, but not replaced)

Sorry for the long post, been gathering lots data to provide a clear picture.

Thanks in advance for all your inputs.

-Emerson.

 

[tominboise]

I'm doing the exact same project (HG + SC) on my 97 this week, so am interested to see what you turn up.

Did you clean out your oil cooler when you had it apart?

 

[baldilocks]

Chill out and accept the situation. The highest temp I saw on your post was 215. I see that regularly during a summer romp on the Rubicon trail here in NorCal.

 

[BajaCruiser94]

No, I didn't do the oil cooler at that time; but I would agree that doing it may be a good idea while having the upper part of the engine off.

 

[Pin_Head]

Sounds pretty normal.

 

[baggar11]

While doing some tests on my driveway after arriving home from a small drive at night wih 90ish weather; temps were 199; then every two minutes or so it will creep up 2*; after 20 or so minutes idling with AC on, temperature reached 217, then I opened the hood, then temperatures came down to 215; increased the idle and I could get them down to 199 again.

Replace the radiator, it's not shedding the heat like it should anymore.

 

[FloridaCruiser813]

Anyone running and external oil cooler ?

 

[Funner]

There's like a bijillion pages on this from NLXTACY's thread that I believed resulted in almost nothing.

I'm at my absolute wits end- truck still overheating despite best efforts

 

[4runnerd]

I haven't read the thread, but does this maybe segue into the difference between the three row brass versus the two row aluminum radiators? At higher temperatures, the thermal conductivity of some metals change; maybe this is where a true difference would be seen between the two.

I have yet to hear anyone give a definitive answer as to why Toyota changed from brass to aluminum; the quick and easy answer is cost, of course.

 

[LandCruiserPhil]

Welcome to SC 80 series

 

[inkpot]

Not really seeing much difference between the 2 fan/clutch setups?
Locals seem to run cool with blue hub wig 25-30,000 CST and the FJ 62 fin fan on SC rigs. I would try swapping in a fresh radiator. Been seeing really good results with the TYC Aluminum units.

 

[NLXTACY]

There's like a bijillion pages on this from NLXTACY's thread that I believed resulted in almost nothing.

I'm at my absolute wits end- truck still overheating despite best efforts

* bad fan clutch
* exhaust leak at O2 #2
* Snork to greatly reduce intake temp

 

[bloc]

I removed my passenger side parking light on a recent trip with elevated temps to quickly see if cooler intake air made a difference.. didn't move the needle at all, and I have the more sensitive temp gauge mod. Numeric water temp gauge going in next time I drain the coolant. Will repeat then.

Yes, not quite the same as a snorkel, but should be plenty cool with 70mph of fresh air being blasted into the fender via the big hole left by the removed light.

And before anyone asks.. I don't want to use a snorkel because I believe they are too restrictive for the vortec I plan to run eventually.

 

[landtank]

If you feel that there is a noticeable improvement in air flow with the orange clutch and stock fan I would suspect the radiator has a problem.

Despite popular belief, a two core aluminum radiator is superior to a 3 row brass. I'd go stock or Koyo.

 

[Funner]

* bad fan clutch
* exhaust leak at O2 #2
* Snork to greatly reduce intake temp

And an $800 radiator, ceramic coated exhaust shields, a misting system, new oem radiator cap, new OEM thermostat... I am glad you have it sorted now, I just lost track of your progress around 50 pages or so, I think.

 

[NLXTACY]

And an $800 radiator, ceramic coated exhaust shields, a misting system, new oem radiator cap, new OEM thermostat... I am glad you have it sorted now, I just lost track of your progress around 50 pages or so, I think.

Oh I'm aware of what I did to mitigate the symptoms but the three causes were narrowed down to those three.

 

[BajaCruiser94]

So, I did more testing yesterday, 106* Weather.

Open Highway - 198-199
Slow stop & go in some soft sand - 203-217
Idling after stop & go max - 217-221

After reaching 221, I hit the highway using some boost, temps got down to 199 in 5 minutes of driving at 60mph.

I did notice some weird noise while the orange fan clutch was at its max, turns out its rubbing the shroud on the bottom part; after comparing in detail with my 94 FZJ80; seems the 97 rad core is a half inch taller and .25 inch wider, that half inch puts the mounting holes for the shroud higher so its closer to the fan and doesn't sit on the bottom tabs completely; engine and tranny mounts were changed last week, since I had shroud rubbing with the ringed fan; it helped, but I still get rubbing at high RPM, only on the passenger side, Its just too close.
I know the PO changed the rad at one time, I dont know where he sourced it or had it custom built, but its not a exact fit as the one on my '94.

Sound like enough justification for a new rad and shroud, now I have to debate between TYC or Koyo, oh my...oh my....

BTW - Hood vents will go in today, will report cooling gains.

Thanks for your inputs.

 

[inkpot]

Pic could help ID your current radiator. New OEM shrouds are cut away some around the bottom where they seem most likely to rub.

 

[BajaCruiser94]

@inkpot Here are some pictures comparing both radiators from the passenger side.

1994 FZJ80 - Stock Engine Setup

1997 FZJ80 - SC - Orange Hub Fan Clutch

You can actually see where the fan has been touching the shroud.

-Emerson

 

[landtank]

check your lower mounts on the radiator. Loosen up the side nuts and try moving the bottom of the radiator forward. I gained quite a bit of clearance after doing this.

Also, did you install the wedge guard on the other side?