General tech question regarding overheating

[Matt76]

Hi All,

Not a Navara question but please help if you can.

A good friend of mine is halfway somewhere between Brisbane and Perth in her approx 05 Rodeo diesel towing a caravan (medium size, not huge).

She just just had to stop for the third time because it is overheating, and is obviously seeing the third mechanic in the third town. From what I know, the first one changed the coolant and thought it would fix it, the second flushed the radiator and thought it would fix it, and now the third one can't get it to overheat again, though he is obviously not towing the caravan along for hundreds of km at a time.

My only suggestion and correct me if it is stupid, is that it should have a transmition cooler (it is an auto) fitted as maybe the gearbox is overheating and causing problems for the engine. Is this possible? Do they have a small cooler from factory or nothing at all? Do they run off the radiator?

She bought the car a couple or years ago as a 1 owner, the NSW police force, and has done a heap of trips from bris to sydney trouble free, albeit without the new caravan.

Any help would be greatly appreciated, even if we can just suggest things for her to look for.

Cheers
Matt

 

[KraftyPg]

Do you know if it's overheating to the point of needing to stop the car or if it's just getting warmer than they expect it too. Out in the boonies car's tend to run a lot hotter and towing vans and just general heat out there will push temperature gauges up and on some cars seeing the gauge rise towards the top of the "normal" range does worry people some times.

 

[KraftyPg]

Oh and something they can try if they are stuck between stops and it's getting hot, is drop the speed but 10 ks or so, open all the windows and run the heater flat out. it wont fix anything but if your desperate to get the car somewhere when it's getting hot it does take some of the heat out of the engine.

 

[Dave]

Is the condensor free of debris ?

They would run a transmission cooler, are they using the air con at the same time ?

Dave.

 

[Matt76]

From what I know, originally it was getting up 3/4 of the way to the hot mark, which it normally never goes near, which as you say Krafty is probably not a huge issue, but she wasn't comfortable with it. The last time she left Port Augusta (wherever the hell that is and got not far out of town and it went to 3/4 again so she turned around and on the way back to town it went all the way to the H, at which point she stopped and let it idle and it wouldn't cool down. Its all second hand information, god knows what she did when it would'nt cool down, hopefully she didnt just switch it off, I would have cruised along at 60km or so, even if it were on the highway.

I am assuming the condensor is clean, it never ever goes offroad and has only done highway work since the 2 mechanics looked at it.

 

[KraftyPg]

Well Port Augusta is expecting 33 and thunderstorms so that's probably not overly hot compared to a summer in QLD but it could still be just a different climate and a different operating temp.

Out in the middle of nowhere I wouldn't have been overly suprised to see mechanics just trying anything but Augusta is a fairly big town so I'd have expected someone to know something. If she's still there they do have a Holden dealer it might be worth calling in, if they are heading towards Pirie there is a Holden dealer there too I'm fairly sure.

 

[Matt76]

Thanks Krafty I'll let her know.

 

[scottybobcat]

If it is auto and doesn't have a cooler the tranny lines will run through the radiator.
Check that the radiator isn't blocked with locusts and bugs.Thermostat or water pump could be knackered.Turn the heater on if just had coolant replaced as it could have an air lock.Check if has thermo fan for air con is working if it has 1.

 

[KraftyPg]

The Holden Stealer in Augusta is next door to Hungry Jacks on the eastern side of town, just over the causeway, otherwise Pirie and Crystal Brook both have them if they are heading coastal but if they are heading inland it might be a bit harder to get a dealer thats anything more than a country mechanic.

 

[Old.Tony]

I'd look at blockages in the radiator - either the fins (bugs) or the cores. If she's not hammering the vehicle, the transmission shouldn't overheat too much.

If it won't cool down while the car's idling I'd suggest it's a blocked radiator and the thing needs to be re-cored - unless the thermostat is stuck, or the water pump's shot.

I wonder if there's a head gasket in need of replacement and the blow-by into the water jacket is causing all the trouble.

I'd go with the thermostat/waterpump/re-core in that order.

 

[justAL]

Simple question.

How fast is she trying to tow it?

 

[tweak'e]

not all vehicles have accurate temp gauges. most will not show a normal rise in temp from going up a hill (probably done so not to alarm the driver). however that also means by the time its reading hot its seriously hot and something is wrong.