Overheating GU TD4.2T

[Spoons]

I have an 02 TD4.2T which overheats badly when towing caravan. I have had the radiator rodded and checked the thermostat - all OK. Replaced the oil in the thermo hub today. Used 2 18mL tubes of silicon oil (Toyota). The hub does not feel any different now than when it had minimal oil in it. Still wont kick in as temp rises.

Any thoughts? Any info greatly appreciated.

Spoons

[AB]

Hi Spoons, don't forget to introduce yourself too when you get a chance in the intros section.

Does it overheat just crusing on the flats or is it just under pressure when powering up hills, etc?

Badly do you mean almost boiling right at the top or just 3/4?

Also, manual or auto?

[AB]

Rodding the radiator is almost a sure way to stop this and you have obviously done it.

What about the correct ratios of coolant? Any chance you may have put too much coolant in last time?

Sometimes people can put way too much coolant in which actually blocks the tubes and makes it worse....Just throwing some ideas around.

[YNOT]

If the fan still won't kick in after re-oiling the hub, replace it. While you're in the area check the fan for cracking around the centre.
Thermostats are only about $30 or $40 dollars so replace it if you're still having issues.
Next thing I would do is replace the water pump.
As AB suggested, make sure you use the correct coolant concentration and never mix different types of coolant.
It's a process of elimination.

Tony

[Spoons]

Thanks for the help everyone. Much appreciated. Manual gearbox, temp goes to first mark reasonably quickly on level road. Turning the A/C off reduces temp slightly (maybe not such a good option for summer in North Queensland). Reducing speed also does the same (I usually try to maintain 90 kmh for a few reasons). Towing a 19' van.

Fan is cracked and will be replaced this week depending on the mail. Going to remove the water pump this morning and have a look at its condition. If it even looks remotely dodgy it will be going too (checked this morning, looks brand new). Assured by Natrad guy that thermostat is OK but might replace it as well.

Just flushed oil side of motor with CEM oil flush (got about 11 1/2 L out), also using CEM Decarboniser and Clean fuel (very impressed with results so far). Just replace gearbox, transfer case and rear diff oil's with Bimrose products (ran out of diff oil for the front, it will get done soon). Again, impressed with the improvement to performance.
Any ideas on where to purchase new hub? Local Nissan dealer wanted $500 which I thought was a little excessive.

Thanks

Spoons

[YNOT]

Try Repco or Ebay for fan hubs and water pumps.

Tony

[Adlarplant]

id suspect the water pimp i replace mine every year

[Spoons]

id suspect the water pimp i replace mine every year

Tried that today. Inside it looks brand new. No pitting, eveything nice and shiny so I can scratch it off the list. Starting to run out of suspects.

Spoons

[Spoons]

Replaced the fan hub yesterday. I've gotta say the new one didnt feel any different to the old one. $175.00 from local Autopro (Dayco brand).

We are going to Brisbane tomorrow (getting some work done to the motor) and eventually to Sydney (visit Mums) and will be towing the van. That should give some indication if any or all of the problem has been fixed. Heres hoping.

[Woof]

I was talking a member of our club at Wednesday night's meeting and he was having the same issue, checked everything and all was good.
Someone told him to put a 5mm spacer on the hinges of his bonnet where it bolts onto the bonnet, this raises the rear of the bonnet so there is an air flow continuously going through the engine compartment.
His problem was solved.