Overheating

Joined
Nov 30, 2015
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23
Location
East Tennessee
One day last week I drove about 60 miles to a trailhead and then drove about 15 miles of moderate trail (with a short section or two of steep crawling and one big creek crossing) to a property for work. Anyway, it was a fairly warm day and I wasn't easy on the truck. On my way back home on the interstate going about 65mph my engine cut off and was overheating. I was able to coast over to the side of the interstate and got a tow to my house. Antifreeze had spewed all over the engine bay so I went ahead and cleaned everything. The next day I inspected all hoses and could not find any obvious leaks. PO had an aftermarket radiator cap so I went ahead and ordered/installed a Toyota cap. I drove it about 1/4 of a mile down the road tonight and then back to my driveway. When pulled in it was overheating again. This time I could see that fluid was pooling up at the bottom of the radiator but not hitting the ground and had sprayed up against the air cleaner. I also noticed that my fan shroud was a little loose and that one of the fan blades was chipped. Chip in the fan blade could be old but its new to me. The motor was obviously very hot but the top of the radiator was cool. Seems like I might have a clog causing coolant to spew/leak. Looks like the original radiator to me and not in the best of shape. Lower radiator hose looks fine but I will probably replace anyway. Anyone else had a similar issue? Thinking about a radiator flush (did this 2 years ago), new lower rad hose and new thermostat (7 years or so ago). Resevoir has fluid. Anything else I should look into?
 

desmocruiser

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Dec 17, 2005
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815
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Big Orange Country
 
 
I don’t recall water pump failures being typical, especially sudden, but could be the cause. Any noise prior to that would be indicative of a failing water pump or fan clutch?

What is the known history of the head gasket?

I am not certain where you are located in ET, but I have a good Cruiser Mechanic. Let me know if you’re near Knoxville and I can send you contact information.
 

ppc

M Go Blue
Joined
Aug 18, 2003
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Nashville, TN
 
 
 
In a quarter mile distance a cold motor is not going to overheat. I may be warm/hot but that is much different from overheating. You just have leaks
 
Joined
Nov 30, 2015
Messages
23
Location
East Tennessee
I don’t recall water pump failures being typical, especially sudden, but could be the cause. Any noise prior to that would be indicative of a failing water pump or fan clutch?

What is the known history of the head gasket?

I am not certain where you are located in ET, but I have a good Cruiser Mechanic. Let me know if you’re near Knoxville and I can send you contact information.
No noises. I have heat as well which I thought would eliminate the chance of a bad water pump but I could be wrong. Fan clutch seems fine but will look into that a little more.

Head gasket was replaced as well as all hoses from PO parts receipts about 140k and it has 180k on it now. None of the obvious signs that it is bad.

I am very close to Knoxville. I live in the Maryville area. I’d appreciate the contact info. Will dig into it myself but will call on someone if it gets too ugly. Need the truck for work and play. Can‘t stand not having it ready to go. Thank you!
 
Joined
Nov 30, 2015
Messages
23
Location
East Tennessee
In a quarter mile distance a cold motor is not going to overheat. I may be warm/hot but that is much different from overheating. You just have leaks
Temp gauge was just below red and it was obviously hot. I gave it some gas towards the end of the drive to see if it would cause it to heat up and it did. May not have technically overheated that time but it would have if driven longer. Pretty sure it overheated when the motor shut off on the interstate.
 

LINUS

Waiting for the Great Pumpkin
Joined
Mar 29, 2003
Messages
5,417
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PNW - WA
 
 
 
Stand over the motor watch it get to operating temp - if it’s got a hole in the rad where a fan blade poked it, you’ll see it if it only leaks at pressure.

If your cooling system is all original, you should expect it needs all new:

Radiator
T-stat
Maybe the H2O pump
Hoses, esp the PHH & FHH
Heater valve
Fan, since yours is boogered

Worth giving the evil eye:
-Fan clutch
-Deciding now when swapping out the brittle radiator if you want to bypass the RR heater / give a critical look at those hardlines & hoses.
 
Joined
Nov 30, 2015
Messages
23
Location
East Tennessee
Stand over the motor watch it get to operating temp - if it’s got a hole in the rad where a fan blade poked it, you’ll see it if it only leaks at pressure.

If your cooling system is all original, you should expect it needs all new:

Radiator
T-stat
Maybe the H2O pump
Hoses, esp the PHH & FHH
Heater valve
Fan, since yours is boogered

Worth giving the evil eye:
-Fan clutch
-Deciding now when swapping out the brittle radiator if you want to bypass the RR heater / give a critical look at those hardlines & hoses.
I am 99% sure it only leaks at pressure. I have let it idle and get to temp a few times while trying to track down the leak. Only time I saw coolant was last night when I decided to drive it again. This is when I saw traces of coolant on the air cleaner and a pool at the bottom of the radiator shroud.

Leaning towards a hole in the rad or bad lower rad hose. I guess I will start cheap with a flush, new lower rad hose, new t-stat, and a koso digital temp gauge since I am paranoid now. Maybe attempt all this and avoid a brand new radiator? New radiator should be expected on a 27 year old vehicle I guess.
 

Howard705

TLCA 5505
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Feb 1, 2013
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1,396
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Central Illinois
 
I am 99% sure it only leaks at pressure. I have let it idle and get to temp a few times while trying to track down the leak. Only time I saw coolant was last night when I decided to drive it again. This is when I saw traces of coolant on the air cleaner and a pool at the bottom of the radiator shroud.

Leaning towards a hole in the rad or bad lower rad hose. I guess I will start cheap with a flush, new lower rad hose, new t-stat, and a koso digital temp gauge since I am paranoid now. Maybe attempt all this and avoid a brand new radiator? New radiator should be expected on a 27 year old vehicle I guess.
Pressure Test it. I prefer to hose things off to flush coolant off- let it completely dry- then Fill- CAREFULLY -install the tester NOT SPILLING- pump it up. If no leaks wait a while check later.
 

LINUS

Waiting for the Great Pumpkin
Joined
Mar 29, 2003
Messages
5,417
Location
PNW - WA
 
 
 
You most likely overheated due to the fan clutch being worn out, but as you said - 27yo radiator.

What thing made of plastic that sees the heat & pressure of a radiator do you trust after nearly 3 decades?

You don’t need fancy, just get the cheapest Koyo from Rock Auto - they were some $125 the last I recall that convo.

But get a real deal ‘Yota t-stat. They’re worth it. $20-25.
 
Joined
Nov 30, 2015
Messages
23
Location
East Tennessee
Well, ended up sending it to local Cruiser mechanic (thank you desmocruiser). He said the fan chipped and punched a hole in the radiator. Also said the clutch had some play in it . His recommendation was to take the radiator to a radiator shop and see if they think it is salvageable. Said that the brass one I have would be stronger than an aluminium and was worth giving it a shot. If not salvageable, I will be looking into a new radiator but sounds like I will have to get an aluminium? I will look into the Koyo. Any one else have recommendations on radiators? I will search the forum also. I use the cruiser for work when I need it, trail riding, and the occasional camping trip with the family. I am normally not just cruising around town with it so I want something solid and don't want to replace another radiator in a year or two.

So far I am looking at a radiator, clutch, fan, and shroud. He will gas test after all that and see if there was any damage 🤞
 

AussieHJCruza

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Jul 8, 2013
Messages
1,501
Location
New South Wales, Australia
 
You'd be better off with an aluminium radiator, aluminium sheds heat better than brazed brass. On the fan clutch, suggest hitting up @NLXTACY at Wits End for a modded clutch, I'm very happy with everything I've got from him.
 
Last edited:

LINUS

Waiting for the Great Pumpkin
Joined
Mar 29, 2003
Messages
5,417
Location
PNW - WA
 
 
 
The radiator for the 95-97 will bolt into your 93.

There's another thread here you should check.out on that subject.
+1

New radiator, end of it.

By the time you repair your 27yo one, you still have a repaired 27yo radiator.
Like a facelift on a vain old person, money not well spent.

Just get a new one - either brass 3 row or aluminum 2 row - either is new & not thermo-brittled / ozone damaged to shyt.

A heater valve is going to cost near the radiator cost if you want the OE type that bolts to the firewall, and it’s as critical a part as the plastic body on the radiator.

Overhaul would be under $400 in parts if you did it all yourself, and you’d be rock solid for a heck of a long time.
 

baldilocks

Battle Ground, WA
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Jan 29, 2014
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5,900
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Battle Ground
 
Do yourself a favor and don’t bother with a copper core radiator. To my knowledge the CSF is the only one available and there is plenty of testimony to its inability to do the job it’s intended for. I don’t like plastic anymore than other people but the fact is that aluminum core
gives up heat more quickly and being the copper cores are brazed together and the brazing transfers heat poorly, the all aluminum core actually has a larger surface area. Aluminum is less dense than copper and therefor has less inclination toward holding heat and the larger tubes found in the aluminum radiators on the market increase tube to fin area where heat transfer takes place.

Some Mud guys down in the desert of the southwest swear by the ultra cheap TYC radiator.
 
Joined
Nov 30, 2015
Messages
23
Location
East Tennessee
FWIW, I am positive my radiator is metal and not plastic. The mechanic said if it was any other radiator other than brass and metal, he would tell me to get a new one. I think his concern is the structural stability of aluminum and not the ability to cool. I definitely see the reasoning behind getting a new one but my gut is telling me to hear what the radiator shop says. There is a reason why it lasted 27 years in the first place right? It would be much easier for him to slap a new one in and collect his money.

Curious to know how many are still running an original radiator on 93 and older cruisers. Come to think of it, I had a 1983 60 that had the original radiator.

Also good to know the 95-97 will fit.

Thank you all for your input. That clutch from Wits End is sweet and I am going to sleep on that. Looks like a solid upgrade and makes sense for wheeling around the Southeast.

Looking forward to the Koso temp gauge. Going to install that as soon as I get it back.
 
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