1HDT Over heat!

[Remydog05]

I know there has been many threads on this.
Ive just spent 40mins reading through some of them.

I Drove my 80 from Melb to Sydney on the weekend with the car trailer empty. I had cheaked all Levels before leaving and it was fine, Ive had my 80 about 6 months and never had a prob with it.

Picked a 800kg car and drove back, the 80 was running fantastic pulling it up the hills at 100ks no probs, and sitting on 105 happy as.

Had to come back through Cann River to drop in Bairnsdale and coming out of Cann up Tonigi hill and noticed the oil presurre was dropping a bit??
Dad saw me watching the gauge like a hawk and said whats wrong? As I was telling him the gauge was moving we both saw the temp gauge head north!

By the time I pulled over it was in the red. Let it cool down and cheaked all fluids, it had spat out a heap of coolant into the overflow bottle and out of that bottle aswell. Pretty much boiled.

As we were trying to figure 1 what had happened and 2 why?? A car load of Mechanics pulled up from Orbost, (Thanks Boys) they helped us out and followed us to help if needed. It DID have bubbles come from the raditator and we all suspected a Head Gasket or Cracked head, (I was shi**##iing myself for $$$$).
We topped it up (it had lost about 3 liters) and it ran fine all the way back to Orbost, cheaked it again Nowa Nowa, and Bruthen and it was fine.
Drove back to Bdale, no probs at about 90klms.

I left it with Dad, got our local Mechanic who has worked for Toyota for 30years to cheack it.

Dignosis!
Pressure tested! (Radiator)
No Bubbles in raditator
No Over heating when driven for nearly Half hour (No Trainler tho)
No Signs at all and seems to Runs fine!!!!!!!!!!!

Maybe an airlock??? If so what Causes them??

I am thinking get the Raidator done by Radiator palce and flushed properly.

Any thoughts are very much welcome!

[shorty_f0rty]

viscous fan clutch fluid level?

[me3@neuralfibre.com]

The gauge is not linear - so t was heating and you didn't notice
http://neuralfibre.com/paul/4wd/toyota- ... -gauge-mod
http://forum.ih8mud.com/80-series-tech/ ... ation.html

And the clutch is the problem I BET
http://neuralfibre.com/paul/4wd/tuning- ... fan-clutch

but check all the obvious anyway (coolant, flow, seals etc)

Paul

[Simo63]

Could be as simple as a dodgy radiator cap letting fluid out until there was enough fluid lost to start warming it up. Or even a sticking thermostat can do something similar.

Try the simple things first.

[dumbdunce]

as much as it pains me to agree with Paul, it is very likely to be the fan clutch.

[me3@neuralfibre.com]

as much as it pains me to agree with Paul.

I'm wounded.

[Remydog05]

Thanks all so far!

AH Many answers and its been seen many times!

Will do the Radiator and Check all Hoses presure test again and check the cap to eliminate that first. Then also cheak and overhaul the fan clutch because that looks like a big one!

Will also look into what I can do about the Gauge, mite even get a aftermarket one???

Thats all great info BUT!

Im not a mechanic but the fan problem or gauge does not explain the fluid loss and the bubbles in the fluid??

Or is it this order

1 Clutch fan not working
2 Causes heating
3 Gauge not telling me the truth
4 Gets hot and fluid spits out to the overflow & boils
5 When we refilled it because it was down on fluid, it then looked like airlocks and bubbles,etc
6 We think HEAD GASKET!!! But wasnt really.
7 Doesnt show up when not towing for a long time because its working with no load.

Any chance the head will still be fine???

[Remydog05]

Oh and any idea why the Oil gauge and Oil Presure was changing?

[me3@neuralfibre.com]

Thanks all so far!

AH Many answers and its been seen many times!

Will do the Radiator and Check all Hoses presure test again and check the cap to eliminate that first. Then also cheak and overhaul the fan clutch because that looks like a big one!

Will also look into what I can do about the Gauge, mite even get a aftermarket one???

Thats all great info BUT!

Im not a mechanic but the fan problem or gauge does not explain the fluid loss and the bubbles in the fluid??

Or is it this order

1 Clutch fan not working
2 Causes heating
3 Gauge not telling me the truth
4 Gets hot and fluid spits out to the overflow & boils
5 When we refilled it because it was down on fluid, it then looked like airlocks and bubbles,etc
6 We think HEAD GASKET!!! But wasnt really.
7 Doesnt show up when not towing for a long time because its working with no load.

Any chance the head will still be fine???

Gets hot
Pushes water into overflow
overflow overflows (too much fluid, or steam)
Cap taken off - overflow will not not "draw back" when steam condenses
Air in system
Air mixes very readily ith coolant - foam and bubbles
no pressure on coolant with cap off - water will "appear" to boil at 85c with agitiation (it's a combination of ingested air and cavitation)

Still might be head gasket - see what happens later

Oil pressure drops as oil thins out when it gets hotter.
Hotter temps expand gaps, opeing tolerances, needing more oil.
Reduced oil pressure.

Yep - could be head gasket
But start simple and work up before you stress.

Paul

[bj on roids]

viscous fan clutch fluid level?

BINGO..

First thing I thought, happened on a couple of 2H and a 1HZ engines I have had!!

I spent big coin on Radiators, new hoses, flushing systems, water pumps, belts, pulleys...

Always the last thing you look at!!

[80's_delirious]

Thanks all so far!

AH Many answers and its been seen many times!

Will do the Radiator and Check all Hoses presure test again and check the cap to eliminate that first. Then also cheak and overhaul the fan clutch because that looks like a big one!

Will also look into what I can do about the Gauge, mite even get a aftermarket one???

Thats all great info BUT!

Im not a mechanic but the fan problem or gauge does not explain the fluid loss and the bubbles in the fluid??

Or is it this order

1 Clutch fan not working
2 Causes heating
3 Gauge not telling me the truth
4 Gets hot and fluid spits out to the overflow & boils
5 When we refilled it because it was down on fluid, it then looked like airlocks and bubbles,etc
6 We think HEAD GASKET!!! But wasnt really.
7 Doesnt show up when not towing for a long time because its working with no load.

Any chance the head will still be fine???

car trailer 500kg?,
car on trailer 800kg, (close to 1.5tonne extra weight)
pushed hard up the hill to 100km/hr,
peak load, max fuel, reduced rpm, high combustion temps,

Gets hot
Pushes water into overflow
overflow overflows (too much fluid, or steam)
Cap taken off - overflow will not not "draw back" when steam condenses
Air in system
Air mixes very readily ith coolant - foam and bubbles
no pressure on coolant with cap off - water will "appear" to boil at 85c with agitiation (it's a combination of ingested air and cavitation)

Still might be head gasket - see what happens later

Oil pressure drops as oil thins out when it gets hotter.
Hotter temps expand gaps, opeing tolerances, needing more oil.
Reduced oil pressure.

Yep - could be head gasket
But start simple and work up before you stress.

Paul

check fan etc as above,
maybe learn to back off a little on the hills when loaded.
drop it back a gear and do 90km/hr up big hills (not 100), 90 or less on hills wont slow your trip much

[Remydog05]

Thanks Crew

The Fan is being done straight after Easter, thankfully I dont need it as Im away with work.

Will keep you posted if anything else.

Thanks again

[KiwiBacon]

Always the last thing you look at!!

Well yeah, pretty silly to keep looking once it's fixed.

[bj on roids]

Always the last thing you look at!!

Well yeah, pretty silly to keep looking once it's fixed.

I know that saying, but, literally the last part of the entire cooling system