running temps on highway seem high

[mrtim123]

Gents,

i had to take the Nav down the freeway to Sydney (from Newy) last week and the running temp seemed a little high.

What is your experience with highway driving? I was cruising on 105/110 which translated to pretty well bang on 3000rpm for most of the time and the needle crept up to the bad side of halfway. Generally i run on about 1/3 of the needle, so it was noticeable for me that it was higher than usual. the crawl up ourimbah hill saw it reach for the other side of 2/3 and had me a little concerned that it would keep going up but it seemed to be ok. Granted it was a hot day, but i was not pushing it hard, it was not over-revving (3k is high for a diesel i know) and the truck had no load in it apart from myself.

am i concerned over nothing here? i'll be the first to admit i may be slightly paranoid as my last 3 cars have had cooling problems and 2 have cracked heads under my tenure - wow, sounds like im brutal on my cars but i promise im not

anyway, let me know what you all think.

Cheers,
Tim

 

[Old.Tony]

Being a 2003 model, it could have a little gunk blocking some of the radiator cores now. Might pay to have it inspected - I'm buying myself a self-illuminated micro inspection camera with 7m lead so I can do this exact task (I just hope I can get the camera into position for it to work!). If not, the top tank comes off for a bird's eye view.

Other possible causes - gunk between the radiator cores blocking airflow. Fan clutch not fully engaging (see next paragraph), airflow inhibited by too much stuff in front of the radiator, not enough coolant, faulty thermostat, failing water pump.

The clutch is not so uncommon. Test it - get the engine good and hot, pull over, turn off the engine and pop the bonnet. Carefully reach in and try turning the fan over with your hand - it should be fairly resistant (quite stiff). If it's not, the fluid couple has deteriorated and it's time to get it replaced.

 

[mrtim123]

some great points there, Tony!

My take on your advice would be:
1. Reverse flush cooling system with quality flush
2. compressed air/pressure washer and clean fins in radiator
3. inspect fan clutch for function

that sounds just like a saturday morning job to me

after that, if still an issue i'll move on to thermostat/pump

Cheers!
Tim.

 

[dylan the villian]

i found the small plastic radiator outlet that connects to the hose for the overflow tank has clean snapped off my radiator so off to the rad shop for an assessment, seeing as the whole top tank is one piece i had to have the whole unit replaced. but whilst there had my entire cooling system flushed as the radiator bloke said nav's do frequently cook themselves from gunk build up in the engine water jackets.

so id say go get her flushed mate, it wasnt expensive at all. a whole new radiator with flushing and new coolant plus labour was $350 for me, so a pro flush would be cheap as. can almost guarantee thats what your issue will be,your issue is exactly what the guy explained to me happens with the navs.