1FZ-FE The Big Overheating Experiment. TESTED SOLVED!!! (1 Viewer)

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AverageTanner Wrote:

I did a complete cooling system overhaul a few weeks ago... TYC radiator, OEM thermostat/water pump/radiator cap, hoses and added aftermarket water and trans temp gauges (my ‘93 is ODB1 so no scan tool option for me). Now running 194 at the hottest on my upper radiator hose in 98° Central Texas weather with A/C on full. Typically it stays around 188°. Before I did all the work

Good work, should serve you well. Hotter weather is coming.


I’m not sure how hot exactly it was getting but I know it was hot enough for my A/C to cut out.

Typically between 220-226° F.....so you were running pretty hot. Should kick back in at about 216° F.


I’ve also been reading lots of the posts about good louvers and think I’m going to add some over the next couple weeks after gathering a little bit more data with my cooling system overhaul (since nobody else seems to have gathered real numerical data on the effect of louvers)

Before you go the 'Louver' route 'mod' your fan clutch (higher CST fluid). I'm is Deep East Texas and we have the same temps as Central Texas (I grew up in Austin) but more humidity to deal with. The fan clutch mod IMO gives a good return for your effort. Evacuates air from the engine compartment better and improves cooling (engine and A/C).
 
just out of curiosity, i wanted to look up the cost of a Ron Davis radiator but only found generic info. If someone has a link to the 80 raditaor and a price, please post up the link here.

Thanks.
@alia176 look at msg #25 in this thread you have a link to R D rad with a price
 
Before you go the 'Louver' route 'mod' your fan clutch (higher CST fluid). I'm is Deep East Texas and we have the same temps as Central Texas (I grew up in Austin) but more humidity to deal with. The fan clutch mod IMO gives a good return for your effort. Evacuates air from the engine compartment better and improves cooling (engine and A/C).

I've got a dent on my hood where it looks like a PO closed the hood on something that was sticking up in the engine bay. It's in a spot that seems to be ideal for the louvers (based on the yarn/high pressure/low pressure testing that has already been completed on this forum). During my cooling system overhaul I replaced my fan clutch with a blue OEM on, is that 10k?

I’m also planning on going full redundancy and installing pusher fans on the front of my AC condenser and trans cooler in the next couple of months to help with idle/slow speed conditions.
 
I've got a dent on my hood where it looks like a PO closed the hood on something that was sticking up in the engine bay. It's in a spot that seems to be ideal for the louvers (based on the yarn/high pressure/low pressure testing that has already been completed on this forum). During my cooling system overhaul I replaced my fan clutch with a blue OEM on, is that 10k?

I’m also planning on going full redundancy and installing pusher fans on the front of my AC condenser and trans cooler in the next couple of months to help with idle/slow speed conditions.

Blue fan clutch is probably more like 6K. I used 20K in mine when I did it...and it seems just about right for Texas weather. I also have a pusher fan in front of my A/C condenser. Helps out with low speed cooling of the A/C.
 
For reference



 
I’m moving down to San Diego from Washington State and the other day was getting the Cruiser ready for its trip and noticed coolant leaking onto the ground so I started investigating
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and discovered a crack in my radiator on the upper plastic cap! I’m glad I noticed it before I got on the road. My TYC is coming in the mail tomorrow so I hope it’s everything everyone claims to be.
 
I’m moving down to San Diego from Washington State and the other day was getting the Cruiser ready for its trip and noticed coolant leaking onto the ground so I started investigating..................and discovered a crack in my radiator on the upper plastic cap! I’m glad I noticed it before I got on the road. My TYC is coming in the mail tomorrow so I hope it’s everything everyone claims to be.
If that's the OEM radiator, it's not surprizing. It's only 22 yrs old. Good example to keep a good watch on anything plastic on our cruisers - especially when it's exposed to heat. Like heater valves, any plastic Y's or T's in your coolant/heater lines or anything plastic under the hood.
 
I just want to put in my $.2
Just completed a 600 miles round trip from Los Angeles to Shaver Lake in the Yosemite with the rig fully loaded with 4.5 ppl, full armors, 37s powered by the mighty 3FE... The cooling performed flawlessly this go around...185-190 F on highway w/ AC, 187-193 F on long duration of hill climb going 55mph up the Grapevine with AC. This is with the Ron Davis radiator, modded green hub w/ 30k oil....I did the same trip last year with a new CSF radiator and new FC with stock fluid and had to pull over twice w/ recorded coolant temp up to 220 plus F...
The only problem i am still troubleshooting is my coolant temp would creep up fast after a long highway run or hill climb to a stop and go traffic where my temp would creep from 187 F to 200 F plus depending on how long the truck sits and drops back to normal as soon as the car started moving again.....
 
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I just want to put in my $.2
Just completed a 600 miles round trip from Los Angeles to Shaver Lake in the Yosemite with the rig fully loaded with 4.5 ppl, full armors, 37s powered by the mighty 3FE... The cooling performed flawlessly this go around...185-190 F on highway w/ AC, 187-193 F on long duration of hill climb going 55mph up the Grapevine with AC. This is with the Ron Davis radiator, modded green hub w/ 30k oil....I did the same trip last year with a new CSF radiator and new FC with stock fluid and had to pull over twice w/ recorded coolant temp up to 220 plus F...
The only problem i am still troubleshooting is my coolant temp would creep up fast after a long highway run or hill climb to a stop and go traffic where my temp would creep from 187 F to 200 F plus depending on how long the truck sits and drops back to normal as soon as the car started moving again.....


@Marco Lau I see the same including the 200F after the highway with the AC full blast. Its ok 93 c or 200 F is no problem

I installed a second SPAL electrical fan said by side with the AC fan manually operated for that traffic jam or slow crawling
 
@Marco Lau I see the same including the 200F after the highway with the AC full blast. Its ok 93 c or 200 F is no problem

I installed a second SPAL electrical fan said by side with the AC fan manually operated for that traffic jam or slow crawling
Good to hear...how well does the SPAL fans do in keeping the coolant temp creep?? Any solid data you can share before and after??
 
............The only problem i am still troubleshooting is my coolant temp would creep up fast after a long highway run or hill climb to a stop and go traffic where my temp would creep from 187 F to 200 F plus depending on how long the truck sits and drops back to normal as soon as the car started moving again.....
@Marco Lau I see the same including the 200F after the highway with the AC full blast. Its ok 93 c or 200 F is no problem

I installed a second SPAL electrical fan said by side with the AC fan manually operated for that traffic jam or slow crawling
You both have probably noticed that this seems to be fan related. What weight of clutch fluid are you running?

Couple your issues with the only way my modified gauge approaches 3/4: Low speed off road towing my trailer on uphill obsticles. Guess what improves or brings down the temp? If I shift into low range, the temp gauge comes right back down to normal (1/2 or less). Why? Engine and fan speed is higher and also running with the lower gear ratios, the engine is not working so hard. The additional stress towing the trailer off road on the engine is compensated by running in low range - even though it's not really necessary for power.

So, what's the common thread - IMHO, fan can't keep up with coolant load. With you guys your vehicle speed is all of a sudden seriously reduced, but your cooling system hasn't adjusted yet to the lighter power demand - still has some cooling to catch up on, but air going through radiator is gone except what the fan can pull. With me, the stress to the drive train, especially the engine, is extreme because of the weight, but the air moving through the radiator is minimal due to the lack of speed. Both point at fan clutch. I"ve got the Witt's end modified clutch with what landtank put in it - I believe it's 15K. I can definitely improve on that - and I probably will.

So what I would focus on would be clutch fluid. I've not read about any examples of SPAL fans significantly improving perfomance in 80s....but never say never....:hmm:
 
You both have probably noticed that this seems to be fan related. What weight of clutch fluid are you running?

Couple your issues with the only way my modified gauge approaches 3/4: Low speed off road towing my trailer on uphill obsticles. Guess what improves or brings down the temp? If I shift into low range, the temp gauge comes right back down to normal (1/2 or less). Why? Engine and fan speed is higher and also running with the lower gear ratios, the engine is not working so hard. The additional stress towing the trailer off road on the engine is compensated by running in low range - even though it's not really necessary for power.

So, what's the common thread - IMHO, fan can't keep up with coolant load. With you guys your vehicle speed is all of a sudden seriously reduced, but your cooling system hasn't adjusted yet to the lighter power demand - still has some cooling to catch up on, but air going through radiator is gone except what the fan can pull. With me, the stress to the drive train, especially the engine, is extreme because of the weight, but the air moving through the radiator is minimal due to the lack of speed. Both point at fan clutch. I"ve got the Witt's end modified clutch with what landtank put in it - I believe it's 15K. I can definitely improve on that - and I probably will.

So what I would focus on would be clutch fluid. I've not read about any examples of SPAL fans significantly improving perfomance in 80s....but never say never....:hmm:
Totally agree with what you said. I am running 25k oil currently in the green hub. As long as I am moving in 4L, water temp will never get above 210 F, my fan pulls so much air that with any sort of rpm above 2.5k, my aftermarket temp gauge will show temp drop within seconds... my problem is when the rig crawls in 4L in extended period of time in just idle speed in 95 degree + weather, the water temp can get above 220 F. Switching from 15k oil to 25k oil definitely helped in traffic and low speed wheeling. I think perhaps adjusting and tunning the FC to engage at a lower temp would definitely help, but I have yet to try that... the rig otherwise runs super cool at highway and hill climbs, I cannot break above 195 F even if I try...
 
$1100 is worth a quality product, no doubt.
 
Totally agree with what you said. I am running 25k oil currently in the green hub. As long as I am moving in 4L, water temp will never get above 210 F, my fan pulls so much air that with any sort of rpm above 2.5k, my aftermarket temp gauge will show temp drop within seconds... my problem is when the rig crawls in 4L in extended period of time in just idle speed in 95 degree + weather, the water temp can get above 220 F. Switching from 15k oil to 25k oil definitely helped in traffic and low speed wheeling. I think perhaps adjusting and tunning the FC to engage at a lower temp would definitely help, but I have yet to try that... the rig otherwise runs super cool at highway and hill climbs, I cannot break above 195 F even if I try...

At 25k oil, isn't your clutch continuously engaged during most warmer months? Wonder how much fractional hp you're losing due to this engagement, just curious. Your poor 3FE has its work cut out based on your sig line of mods!
 
At 25k oil, isn't your clutch continuously engaged during most warmer months? Wonder how much fractional hp you're losing due to this engagement, just curious. Your poor 3FE has its work cut out based on your sig line of mods!
The motor is no doubt working and not complaining a bit. It idles smooth and has zero oil consumption and probably in the best shape of its life. I do long trips regularly with my brother in his modded JKU on 37s and the 3FE holds its own ground against more modern powerful engines, and it is just a work horse that keeps on trucking approaching 30 yrs @ 230k miles.
 
Does the Ron Davis radiator have more rows of cooling tubes like the TYC or is it like the stock radiator core?
 

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