WH 3 ltr CRD 2007 OVERHEATING?

[hotqld]

After giving the JGC some attention:
Fixed air bag light DTC and evic warning.
Fixed leaking provent plumbing.
Replaced Glow Plug module, fuel rail sensor.
Replaced Fuel, engine and auto filters.
Replaced oils, diffs, engine, transmission and transfer case.
Scan, all DTC gone.

Left engine cover off and towed boat 1000kg flatish roads temp climbed to one tick off red and fans racing at traffic lights.
Topped water right up filled overfilled to very top took 3 ltrs.
Started motor:
Top radiator hose collapsed, took radiator cap off hose returned to normal.
Drove home without boat, radiator cap half tight, keeping revs below 2000.
Temp only went 1 tick above mid range.

Could it be thermostat or does the motor cover form a critical function for cooling directing air around the motor?
I have left the cover off before, but never towing.

Scanned again, no DTC? but water tank now empty..

Thoughts?

[Clarky]

Don't think its the cover, mine hangs permanently on the wall.
Towed 5000k's to Airlie Beach & back last year and no temp issues.

I would guess the thermostat, the bottom hose that connects to the water pump has a wire coil inside it to stop it collapsing but the top hose doesn't, the fact it was sucked in means on blockage in the radiator it collapsed due to the negative pressure created by the water pump trying to draw water through the radiator with the thermostat closed.
Had it happen to a Bommodore I had on the 80's.

[hotqld]

Back to the overheating problem, it stayed ok for 24 hours 100klm, then serpentine belt broke. and overheated, no power steering etc and a tow truck home.
The belt looks ok no cracks etc, just ripped in half.

But the water pump is locked solid, I tend to think it should turn freely.
Am I on the right track to pull this off and have a look?
And where to pick these up from?

[valpacer]

Its stuffed. Replace.

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[hotqld]

What a job, Do you do it with mirrors and feel? and flexible sockets.
Or remove stuff?
Know of any instructions / utube anywhere,

[timbotrog]

Is there a FSM available with a description on the job ?

[valpacer]

Its tight alright. Pulling the radiator etc makes it easier. By a little bit.....

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