coolant out the overflow hose

[Ade]

You meant the coolant was at full to the top (not at the 'F' level) in the o/tank? It need to be full to the top, to the tank cap for the coolant to flow out from the o/flow tank. If it is the case, I assume your situation might be this..as you drive home that day, your coolant was flowing out to the o/flow tank as it's suppose to when the cooling system reach pressure rated at the rad cap. As you got home while your engine was still warm, it still flowing out coolant because you might have a defective rad cap. As the engine cool down overnight, the cooling system suppose to produce vacuum and sucks in coolant from the tank but again assuming your cap is defective it didn't.

Hope it didn't get to the head mate..touch wood!

[ozzyboy]

no sorry. the o'flow bottle , everytime i looked, has been at the full line.
what has me concerned is that it seemed to of lost maybe a litre of coolant (guess) out the o'flow bottle when i turned it off, but the next morning, the o'flow bottle is still at the full line and the radiator is still full.
Where did the (litre) on the ground come from is where i am stumped

ozz

[Skull]

This is the Cap and cooling pressure test proccedure and pressure values from nissan manual for ZD30.... I am of course assuming it is a ZD30. I am almost certain tho that there is only one pressure cap for diesels in the patrol range.

System Check
WARNING:
Never remove the radiator cap when the engine is hot. Serious
burns could occur from high pressure coolant escaping from
the radiator.

Wrap a thick cloth around the cap. Slowly turn it a quarter turn
to allow built-up pressure to escape. Carefully remove the cap
by turning it all the way.

CHECKING COOLING SYSTEM HOSES
Check hoses for the following:
I Improper attachment
I Leaks
I Cracks
I Damage
I Chafing
I Deterioration

CHECKING COOLING SYSTEM FOR LEAKS
To check for leakage, apply pressure to the cooling system with a
tester.
Testing pressure:
98 kPa (0.98 bar, 1.0 kg/cm2, 14 psi)
CAUTION:
Higher pressure than specified may cause radiator damage.
CHECKING RADIATOR CAP
To check radiator cap, apply pressure to cap with a tester.
Radiator cap relief pressure:
Standard
59 - 98 kPa
(0.59 - 0.98 bar, 0.6 - 1.0 kg/cm2, 9 - 14 psi)
Pull the negative pressure valve to open it.
Check that it closes completely when released.

Engine Cooling System Specs.

Radiator
Cap relief pressure
78 - 98kpa or 11-14psi
Leakage test pressure
157kpa 0r 23

Thermostat
Valve opening temperature
Tropical type 76.5°C Standard type 82°C
Valve lift
More than 10mm/95°C

[ozzyboy]

4.2 efi petrol / gas

will check the relief pressure for the 4.2 and have a go at it tomorrow
I do have a spare new cap in the car. will test before i put new cap on ( mainly just for closure)

[Skull]

Ah ha. Looks like you got one up there whilst I was typing. Tis cool. After reading yours last I don't think that info will be helpfull to you but others may find it handy so I will leave it.
Just looked up your Intro and found you are in a 4.2qy. No ZD here then. Was way off.

I suggest you mark the side of your resevoir tank when cold in the morning. Check it every morning and see if the level changes. It may not be a litre you have lost if you say it still looks full. Can't hurt to do a full flush like I sugested earlier either. Peice of mind beening summer and all. Not real familiar with the 4.2 but just checked the manual. 16-18psi on the cap, boiling piont of water at this pionts is 106Deg C with out glycol. If in doubt change it.

[Ade]

Did you top up or fill the over flow tank to the F level or right to its neck?

On a healthy cooling system, the coolant level in the over flow tank suppose to be at F level when the engine is fully warmth to its operating temperature. This is because as the coolant warms up, it'll expand and pressure builds up to the rated as on the radiator cap. When the engine cools down, realy2 cool lets say over night, the coolant in the system retract, creating vacuum and sucks in coolant from the over flow tank to nearly around L level.

[Ade]

Could it be you had your over flow tank over fill to the top mate? If you had it will surely flows coolant out of it. One more thing, as you go along never spill coolant to the engine parts especially the belts. Quickly rinse off with water any coolant spilled..

[ozzyboy]

nah coolant in o'flow bottle was only to f line. Motor was cold when i filled to there.

[Skull]

She might just have been hot after a big day and had a lil spit mate. Quick boil as ya pulled her up. Give her a birthday and all should be sweet.