Running warm, looking for theories

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I think you have a problem with your head gasket, do not drive for extended periods of time!

I would change oil and filter to synthetic untill you can do your head gasket replacement, also since you are going to be there you can get your head machined and do a valve job!

Good luck!

Also look into your radiator, i think you are going to need a flush after you are done with head gasket!
 
Oh! do you see the water circulating on the radiator?
 
HI there, bought my first LC a few weeks ago, and on the way home it was overheating. I had simular symptoms. The previous owner had mixed the Toyota RED coolant with GREEN. Never do this... this caused the radiator to clog up. In my case it clogged it just enough to cause the temp to go up and then go down.
I replaced the radiator and water pump while I was at it... never had a problem since. I would recomment roding and cleaning out the radiator.
Also, based on the photo of the oil cap, I would check your oil to be sure there is no water in it.... if so then you have a head gasket problem.
Good Luck!
 
Take a good look at your radiator. I never even knew I had a leak until I was running it in the summer with the A/C on and the system was completely pressurized. The truck then started getting hot. I had a pinhole that sprayed pink mist all over the engine bay. I replaced fan clutch, radiator, condenser, thermostat, hoses, water pump and belts and it has been a champ since.
 
Oh! do you see the water circulating on the radiator?

I'm not 100% sure how to tell. At no point did I see the water level drop after I refilled and started it, nor did I feel any fluid coming through the upper rad hose. In fact, something that is suspicious to me is that the coolant that came out when I changed the thermostat was orange in color. Since I refilled with distilled water shouldn't that have mixed and turned the water orange as well? I only ever saw the new water sitting on top.
 
HI there, bought my first LC a few weeks ago, and on the way home it was overheating. I had simular symptoms. The previous owner had mixed the Toyota RED coolant with GREEN. Never do this... this caused the radiator to clog up. In my case it clogged it just enough to cause the temp to go up and then go down.
I replaced the radiator and water pump while I was at it... never had a problem since. I would recomment roding and cleaning out the radiator.
Also, based on the photo of the oil cap, I would check your oil to be sure there is no water in it.... if so then you have a head gasket problem.
Good Luck!

I've been wondering about the radiator since yesterday. What do you mean by "roding?" I have a Blackstone kit and am wanting to send off an oil sample before I make a final determination, but unfortunately the girl is starting to display more and more signs of a bad HG. :confused:
 
I've been wondering about the radiator since yesterday. What do you mean by "roding?" I have a Blackstone kit and am wanting to send off an oil sample before I make a final determination, but unfortunately the girl is starting to display more and more signs of a bad HG. :confused:

"Rodding" is something that any radiator shop can do. They will take the radiator apart and run small rods through the holes to ensure it is not clogged up. At the same time it cleans it out if it is plugged. If you plan on keeping this car a long time you may consider dropping a new radiator in. That eliminates that as a suspect.
 
I'm not an expert, but if you left your cap off the entire time, the system wouldn't have pressurized and mixed. If the coolant is orange, immediately flush and refill your system. It is either green mixed with red or someone may have put Dexcool in it.
 
Bring engine to normal temp. about 170 and then open radiator cap , be carefull with pressure and NOW you can see if water is circulating, have somebody help accelerate engine to make it more obvious, also post if you notice anything unusual inside radiator!

Can you also post a picture of your dip stick to see how the oil looks like!
 
Bring engine to normal temp. about 170 and then open radiator cap , be carefull with pressure and NOW you can see if water is circulating, have somebody help accelerate engine to make it more obvious, also post if you notice anything unusual inside radiator!

Can you also post a picture of your dip stick to see how the oil looks like!

Will do, thanks!
 
No reason to have the cap on to bring to temp. All it does is add risk of burning you. Just leave the cap off and let the truck heat up.

Once the thermostat opens up (around 190) then you will start to see coolant "flow". It's not a rush of coolant the way a 60's small block chevy's radiator would flow but you will see movement or "churning". The coolant will look rather still until the thermostat opens.

Take temps of the inlet and outlet of the radiator, both before and after the thermostat opens.
 
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1) The discolored oil on the bottom of the oil cap means NOTHING. That can be condensation from the engine going through dewpoint and moisture condensing on the bottom of the cap.
2) What color is your engine oil? If it looks like chocolate milk, do not run your engine. That means that the coolant has mixed with the oil and coolant does not lubricate well (forget about the synthetic comment above)
3) As @NLXTACY stated above, once the thermostat opens, you will see coolant flow in the top of the radiator. It will go from LEFT to RIGHT when sitting in the truck.
4) You coolant should be red or green, not brown, orange, or otherwise. If red and green have been mixed, you will get a brown sludge with a greenish tint.
5) Your entire cooling system only holds about 4 gallons after a complete drain (even pulling the plug in the side of the block). How much water did you add?
6) Definitely change your oil and do a Blackstone analysis on the oil pulled out. That will pinpoint it if there is a problem with the HG failing and getting into the oil.
7) After you refill the radiator with water and run it, as it warms up, the coolant will expand and may overflow your radiator. That's OK except it makes a mess. Short fill it about 1/2" to help allow for that. Fill the radiator, then park with the front end up on ramps or very uphill with your heater slide on "hot" in order to circulate the coolant and eliminate the air bubbles. This may take 3 or 4 cycle times to complete. I filled mine with the front up, then drove it around and parked overnight with the front uphill. I rechecked in the morning and did the same again. It took 3 times for mine to stay full.
8) Make sure you install a new radiator cap from TOYOTA. The aftermarket ones don't quite fit right and may not be set properly for the pressure. My old radiator cap was clogged up on the spring and would not relieve, causing my radiator to explode after a sudden heating event.
9) If it turns out you do have the sludge, I would just purchase a new radiator rather than having your old one rodded out. The plastic top on these are known to fail drastically due to numerous heat cycles. (A new radiator comes with a new cap) New radiator is $385 +/- from CDan.

Good Luck!
 
This is why I keep advocate getting a Blackstone sample before buying an 80 - or just assume there is a head job in the near future. The more I hear about "recently purchased" 80's, the more I think a case of overheating, and the following suspicious HG issues, are pretty much the primary reasons people put their 80's up for sale. (Mudders excluded of course!) I mean, unless a person is facing a multi-thousand dollar repair bill why in the world would they sell a good Land Cruiser - particularly with current gas prices?
 
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"1) The discolored oil on the bottom of the oil cap means NOTHING. That can be condensation from the engine going through dewpoint and moisture condensing on the bottom of the cap."

I agree with the second sentence, but not the first.:)
 
Time will tell...
 
No reason to have the cap on to bring to temp. All it does is add risk of burning you. Just leave the cap off and let the truck heat up.

Once the thermostat opens up (around 190) then you will start to see coolant "flow". It's not a rush of coolant the way a 60's small block chevy's radiator would flow but you will see movement or "churning". The coolant will look rather still until the thermostat opens.

Take temps of the inlet and outlet of the radiator, both before and after the thermostat opens.

Thank you for the reply. I will check again and look more closely to see if I see movement. Do I need an IR gun to take those readings, or is there another way?
 
1) The discolored oil on the bottom of the oil cap means NOTHING. That can be condensation from the engine going through dewpoint and moisture condensing on the bottom of the cap.
2) What color is your engine oil? If it looks like chocolate milk, do not run your engine. That means that the coolant has mixed with the oil and coolant does not lubricate well (forget about the synthetic comment above)
3) As @NLXTACY stated above, once the thermostat opens, you will see coolant flow in the top of the radiator. It will go from LEFT to RIGHT when sitting in the truck.
4) You coolant should be red or green, not brown, orange, or otherwise. If red and green have been mixed, you will get a brown sludge with a greenish tint.
5) Your entire cooling system only holds about 4 gallons after a complete drain (even pulling the plug in the side of the block). How much water did you add?
6) Definitely change your oil and do a Blackstone analysis on the oil pulled out. That will pinpoint it if there is a problem with the HG failing and getting into the oil.
7) After you refill the radiator with water and run it, as it warms up, the coolant will expand and may overflow your radiator. That's OK except it makes a mess. Short fill it about 1/2" to help allow for that. Fill the radiator, then park with the front end up on ramps or very uphill with your heater slide on "hot" in order to circulate the coolant and eliminate the air bubbles. This may take 3 or 4 cycle times to complete. I filled mine with the front up, then drove it around and parked overnight with the front uphill. I rechecked in the morning and did the same again. It took 3 times for mine to stay full.
8) Make sure you install a new radiator cap from TOYOTA. The aftermarket ones don't quite fit right and may not be set properly for the pressure. My old radiator cap was clogged up on the spring and would not relieve, causing my radiator to explode after a sudden heating event.
9) If it turns out you do have the sludge, I would just purchase a new radiator rather than having your old one rodded out. The plastic top on these are known to fail drastically due to numerous heat cycles. (A new radiator comes with a new cap) New radiator is $385 +/- from CDan.

Good Luck!

2) The oil on the dipstick looked pretty clean; transparent and not as dark as I would have expected it to be with a couple thousand miles on it (since PO had it changed).

4) I will attach a pic later of the coolant that came out and get feedback on the color.

5) I used 1 gallon between the overflow tank and the radiator.

7) Thanks for these instructions, I have been wondering about the burping procedure.

8) Any way to tell from the attached photo whether this cap is OEM or not?
 
8) Any way to tell from the attached photo whether this cap is OEM or not?
Here's a pic of my 94's cap, which uses a different radiator.

Can you post a pic of the top of yours, and of the dipstick?
ImageUploadedByIH8MUD Forum1426032760.051007.jpg
ImageUploadedByIH8MUD Forum1426032772.775475.jpg
 
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Like Stylo07's cap, see the spring on the bottom? Make sure that is clean and not packed with gunk or stop leak. Mine was filled in to the point that the spring would only move about 1/16", not enough to relieve full pressure.
 
Here is mine Stylo. It looks to be the same. I'll get a pic up of the dipstick shortly.

image.jpg
 

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