80 Series Cooling Issues (1 Viewer)

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Joined
Aug 18, 2010
Threads
58
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Location
the west desert
Website
shadowlightpsych.com
Ok fellas, here is the deal,

First a little background: I went to work as a technician at a Utah Mitsubishi dealer in 92. Way back then I bought a little used 89 two-door Montero just to drive to the trail head, and maybe take skiing. I suppose because I enjoy life off the beaten path, and because I live only a few hours from the red rock country, I eventually found my self out on the trails pushing this little rig to its limit. And so that's how I just kinda stumbled into this crazy sport.

Fast forward 15+ years, a marriage, and 4 kids later (lotta kids I know, but I live in Utah... when in rome!.. only 1 wife though ;)). The 91 4-door Montero we had moved up to was getting pretty old and beat. And though I think the Montero is a formidable vehicle, It definatley has its limitations: gearing, IFS, lack of power, limited aftrmrkt support, etc... So I started looking around and noted the 80 series Toyota Land Cruiser, did some research, and realized these things came from the factory with a solid axle, and even front and rear lockers! And it had enough room for my wife and kids, our dog, and all our gear to keep us alive in the backcountry for days!?! How cool is that.

For months I searched for a decent cruiser and spent a lot of time test driving overpriced junk, and never found one with less than 120k miles. Then a miracle; In the spring of 2009 I found a 95 with only 42k original miles! I had to fly 5 states away to Pick it up, and no e-locks, but it was like a new car (even though it was 15 years old). I picked it up for under $10k!

A few months later on a weekend trip out in the Utah west desert we ended up on a gnarly trail in the middle of nowhere where I mangled the factory running boards and blew out one of the street tires this thing was sporting. That was all it took. Six months and a good chunk of my retirement fund later, we now have a cruiser that can handle the way we like to vacation.

Now here is the problem: this spring we did the Hole-in-the-Rock trail in southern Utah and I noted that at times I was loosing my a/c. Half the time I was towing my buddies broken down Defender 90 so I didn't worry too much about it. Then two days ago we were down in the same area (Hotel Rock) and again I lost my a/c, then my air compressor stopped working, and my fuel tank began boiling.

After tapping into the infinite wisdom that is available on mud, I am certain I have an air flow/heat dissipation problem. Under the hood I am running a TRD supercharger, Dual batteries W/factory trays, the marine switch, and all the cable to power front and rear winches; a sun performance air compressor with stainless lines for arb lockers. Then there is the arb front winch bumper to block even more air flow. And I have added a million pounds of other **** like custom rock sliders, an arb roof rack, Slee rear bumper, rear winch & plate, oem aux fuel tank, 5 gal air tank and stainless lines, all rolling on 315s, a 4" slee lilft, and 4.88s. Then put my family and all our gear in it... It's really no wonder the thing gets hot under the hood.

So I'm thinking a pusher fan is in order? I also question the fan clutch. I know how a Mitsubishi clutch is supposed to behave, but I'm not sure if this one is working properly, seems to move a little slow and not as much resistance as I would think it should have even at operating temp, but it only has 65k miles on it, but maybe its beginning to fail? Cutting holes in the hood is not something I enjoy thinking about but would consider if I found a scoop that was a good fit. Is it necessary? I'm kinda anal retentive and tried to keep everything true to the factory as possible. I'm not looking for the cheapest fix, but I am looking for the most effective and reliable solution. Any advice from somebody who has been in the same boat would be greatly appreciated.

Shawn
 
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Drain your fan clutch and put in some 10K CST

Ditch the hood entirely, who needs it anyway?
 
So definately a aux fan is in order. I also question the fan clutch. I know how a Mitsubishi clutch is supposed to behave, but I'm not sure if this one is working properly, seems to move a little slow and not as much resistance as I would think it should have even at operating temp, but it only has 65k miles on it, but maybe its beginning to fail? Cutting holes in the hood is not something I enjoy thinking about but would consider if I found a scoop that was a good fit. Is it necessary? I am extremely anal retentive and every thing I have done has been as true to the factory as I could possibly get it. I'm not looking for the cheapest fix, but I am looking for the most effective and reliable solution. Any advice from somebody who has been in the same boat would be greatly appreciated.

You're on the right track with the fan. Check to see if you can stop it from turning while the engine is running. If you can easily stop it, then it's no good. Either fluid is shot or it's leaked out.

If the fluid is leaking out (which may be difficult to impossible to tell), then you may need a new fan clutch. Cdan can get you a new blue hub one.

Either way, refill with high fluid (your area I might look at the 30k fluid). You can also look up Landtank's thread on the blue hub fan clutch on how to adjust the temp it opens at.

Tons of threads on fan clutches, if you do a bit of searching.

"fan clutch" site:forum.ih8mud.com/80-series-tech - Google Search

On the electronic pusher fan, it's a good idea IMHO. Helps a lot at low speeds, and can help cool the truck faster if setup with after run.

Sumotoy had a good series of threads, called the ABC's of 80 series cooling.

sumotoy ABC site:forum.ih8mud.com/80-series-tech - Google Search
 
First and foremost, welcome :flipoff2:

Sounds like a pretty sweet rig you have there. Maybe you could do a ROTF writeup on it (make sure you include pictures, it keeps everyone happy :D)

I'd start with replacing the fan clutch fluid and possibly the fan itself. You must have come across some of the numerous fan clutch threads in your searching, so I won't go into detail, but if you have the original black hub fan clutch, some 10K cst silicone oil should wake it up. I believe there are also a couple of fan blades that folks have used to replace the wimpy, explosion prone TRD SC fan.

I would skip the holes in the hood and additional electrical fans. IMO, these tend to fix the symptoms of the problem (excessive underhood heat) instead of curing the real culprit (wimpy fan clutch, clogged rad etc).

Hope that helps :cheers:
 
I believe there are also a couple of fan blades that folks have used to replace the wimpy, explosion prone TRD SC fan.

Tools R Us (who I'm sure will weigh in here soon) has often recommended the 3FE fan. Seems to fit perfectly with the super charger.

I would skip the holes in the hood and additional electrical fans. IMO, these tend to fix the symptoms of the problem (excessive underhood heat) instead of curing the real culprit (wimpy fan clutch, clogged rad etc).

Skipping the holes I agree with, electric fan I don't. Nothing wrong with adding a pusher fan, it was a stock option on many overseas rigs. The engine driven fan doesn't do that much at low speed (near idle), so an electric fan can significantly help with that.

Helps keep the AC blowing cold as well. :grinpimp:
 
Tools R Us (who I'm sure will weigh in here soon) has often recommended the 3FE fan. Seems to fit perfectly with the super charger. ...

Yep, local S/C experience has shown that the fan is the most important change for cooling improvement, next is clutch tuning. The 3FE fan has shown good results, the fit, spacing is about as dead on as you could ask for.
 
Shawn,

Former 91 and 99 Montero owner here. Miss the bouncy driver's seat, the reclining 2nd row seats, and the factory "you're about to tip over" bubble guage in the dash.

Have you had the radiator boiled out since you got it? Many owners (or their mechanics) mixed green coolant with the Toyota red and a pretty impressive amount of sludge ended up in a LOT of 80 radiators over the years. We don't hear of this much anymore but as "young" as yours is the sludge may still be an issue for you as you've likely got the original radiator in there which is fine - great heat exchanger. I'm assuming this is the case as we're talking cooling issues and you don't mention putting a new one in among your mods.

So, I agree with the fan change, the fan clutch change, and to that I'd add strongly consider having the radiator professionally rodded out or steam cleaned or whatever will get what is essentially a grey/green clay out of the insides (it settles at the bottom and searching here will show some amazing pictures).

Your tranny also pumps a lot of heat into the mix and I'd do the "Simple Green" treatment on it to ensure the fins are clean and not coated with road grime/dust. If you don't pull the rad, ditto on it as well. Searching here will pull this up.

Welcome, and nice sounding rig.
 
I installed a pusher fan on my truck and saw a pretty good improvement at idle or very slow driving. My suggestion is that if you do install a pusher, make sure you get your electical connections done right. Mine came lose after about a year and now I just have a fan sitting there blocking even more air flow.

I have a friend with a mud buggy that runs two radiators. It's an old pickup truck and it has one in the traditional spot and a second one in the bed w/ a pusher fan on it. It's so when the front one gets caked with mud, he still has an effective radiator. You could rig up something if you want to get crazy. For the record, I don't think you should, I'm just throwing out ideas.
 

IMHO, it depends on the clutch, what clutch is in your rig? You have a S/C and like to play in the desert, I would go thicker.
 
Guy take the hood bolts of and add an inch of washers to raise the rear of hood on mounts and then remove rubber seal on under side rear to allow air travel...I allways remove the guts of thermostats and leave just the brass caseing to slow travel enough for cooling but not restrict, but thats just me.
 
IMHO, it depends on the clutch, what clutch is in your rig? You have a S/C and like to play in the desert, I would go thicker.
I'm running the original clutch. This thing only had 50k miles on it when I installed the S/C and it looked like a brand new car under the hood. Also something about other manufacturers and thier odd colored coolant and associated gasket problems inspired me to convert the coolant from the red to green... um bad idea? you take the cap off the radiator and it looks shiny and new inside, and I'm not getting any kind of "grey sludge" in the overflow.
 
IMHO, it depends on the clutch, what clutch is in your rig? You have a S/C and like to play in the desert, I would go thicker.

I agree. I have a 95 SC'd rig as well. Changed the blue fan clutch fluid to 15K CST, helped a little, but would go thicker if I were you. You can also tune the fan clutch. Landtank has a good write up on how to do it.

I would also check the radiator. My truck was running very warm when I got it. Had the fan clutch, thermostat replaced, and radiator rotted out. that fixed it. I also changed the ring fan to a fan for a 4runner I believe. CDan can tell you which one you need. You have to trim the bottom of the fan shroud a bit, but it is no big deal. Regarding the radiator, if I had it to do over again, I would have dropped in a 3row brass unit from the earlier model 80's. its a direct fit as I understand it.

hth
 
Guy take the hood bolts of and add an inch of washers to raise the rear of hood on mounts and then remove rubber seal on under side rear to allow air travel...I allways remove the guts of thermostats and leave just the brass caseing to slow travel enough for cooling but not restrict, but thats just me.

That isn't good advice for a 1FZ if the goal is improved cooling. It has a bypass system, the thermostat opens to the radiator and closes the bypass at the same time, if it is gutted it will bypass full time, running hotter.
 
Hey thanks for the feedback, you guys are awsome! To clarify things I have not had overheating issues with the truck. Before and after the S/C install the temp gauge needle has never left dead center after warm-up, but maybe the factory gauge isnt reliable. I have lost my a/c when creeping off road, and noted extreme pressure and vapor build up in the fuel tanks I assume due to the return fuel being super heated as it passes through the engine compartment.

I have converted the coolant to green but I flushed the system thoroughly before hand. I am wondering now if that was a mistake, but anyway, the radiator still looks very clean inside and out, like brand new, so I dont think that is the problem. But I am still running the original thermostat. Are there t-stats with varying temp ranges?

Im pretty sure most of the problem lies with the fan clutch, and possibly the need for a pusher fan. I have shaken off the attention deficit disorder long enough to go back and read some of the thread history on this issue. Who new you could change the oil on a fan clutch! 18 years of working at a dealership and I always just recommended replacing the whole thing when there was a problem.

The questions I have are, first, what is the difference between a clutch with a "blue hub" and my clutch that is not blue? Is it some sort of aftermarket part? Is it superior to the original? If so, why? And does a new "blue hub" have to be adjusted and the oil changed before installation? How often should one change ones fan clutch oil anyway?

Thanks again for the help with this!
 
I'm running the original clutch. This thing only had 50k miles on it when I installed the S/C and it looked like a brand new car under the hood. Also something about other manufacturers and thier odd colored coolant and associated gasket problems inspired me to convert the coolant from the red to green... um bad idea? you take the cap off the radiator and it looks shiny and new inside, and I'm not getting any kind of "grey sludge" in the overflow.

Original on a '95 is most often an Eaton, if so the hub that mounts to the pulley will be plain steel. They are a good clutch, I would confirm type, fill with 15K and see how that works. Combined with a better fan it should give a nice improvement.
 
Original on a '95 is most often an Eaton, if so the hub that mounts to the pulley will be plain steel. They are a good clutch, I would confirm type, fill with 15K and see how that works. Combined with a better fan it should give a nice improvement.
Thanks for the advice. I found a 3FE fan at a local scrap yard for $40 bucks. Where do you recommend I get the oil?
 
Thanks for the advice. I found a 3FE fan at a local scrap yard for $40 bucks. Where do you recommend I get the oil?

I would price a dealer (cruiserdan?) new fan. Like any plastic, they become brittle over time, so if not hugely expensive I would start with a new one?

The fluid is available at hobby stores that specialize in R/C cars, it's called "diff fluid".
 

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