D22 Overheating issue

[user 50980]

I hope this is the right thread but didn't fit in any other category.

I know this topic has been discussed a lot but the informations I found didn't help me.

Since a while my 2010 Navara D22 YD25 starts to overheat. In the beginning it was only under load when driving faster then 105 km/h up a hill in 5th gear.

Now it starts doing it when driven faster the 95 km/h on a straight highway. Drops the temperature again when you drive "just" 90 again.

Guesses so far:
- old cooling fluid
- blocked radiator apots
- broken thermostat
- spotties blocking the air in front of the radiator

I will take care of all of that but wanted to have some input while I'm on it that I don't miss anything obvious.

Also (when a friend borrowed the Nav) a mechanic said it's a common problem an the schaust airflow is booked which would require him to take everything apart and clean it which would be a 2 days job. Never heated that one before

Thanks in advance for any insight.

 

[KevinE]

I'm wondering if your EGR valve is failing?

 

[tweak'e]

radiator is the first place to look.
the 2nd is flow restriction ie thermostat not opening up or work out water pump. often just change all 3 at the same time.

the other i would check is if its going through water. very very common for light diesels to crack the head when overheated.

 

[TCN]

Clutch fan faulty, thermal fan not working, or if in fact if it has overheated at one stage cracked head, the heads in these engines are made of cheese and the factory temp gauges are rubbish so slight movement on the gauge = good chance cracked head

 

[shane_1]

I redlined my factory temp guage a few times, had plenty of steam coming out the reservoir overflow pipe, and no cracked head (thank all the gods).
That's before I replaced my radiator with a cheap chinese one and no overheating again. But as tweak'e says, do thermostat while you're at it and check the water pump.

 

[user 50980]

I'm wondering if your EGR valve is failing?

Haven't considered this. Will check it

radiator is the first place to look.
the 2nd is flow restriction ie thermostat not opening up or work out water pump. often just change all 3 at the same time.

the other i would check is if its going through water. very very common for light diesels to crack the head when overheated.

Is there any way I can check the water pump? But yes it's a good option.

Doubt the cracked head. No indication whatsoever for this. Don't go through any water.

Clutch fan faulty, thermal fan not working, or if in fact if it has overheated at one stage cracked head, the heads in these engines are made of cheese and the factory temp gauges are rubbish so slight movement on the gauge = good chance cracked head

Will check the fan as well. Was on my list but didn't write it in

 

[user 49350]

I did all of thise things, pump, thermostat, viscous fan, egr block and it was actually the radiator. Put a new one in and no more overheating. Took the top and bottom tanks off - nearly half the tubes blocked with some sort of grainy sand stuff. I was told that a 10 year vehicle would probably be a blocked rad.
Attached photo is of bottom tubes, they were nowhere as bad the top tubes.

 

[KevinE]

Unless you're 100% sure that it's actually overheating, another thing I'd check is the coolant temperature sensor, they do fail.

I had one fail & it started doing some crazy things to the needle on the temp gauge on the dash. They're very easy to test. I like this video, it's not a Navara, but you'll get the idea;

 

[tweak'e]

Is there any way I can check the water pump? But yes it's a good option.

i know mechanics who will just replace it when doing the rest as checking it involves removing it.

radiators no1 on my list. what makes it a double hit is that lack of heat transfer to the air means the fans thermostat won't work so the fan won't work.
radiators are fairly cheap and easy to replace.

 

[user 50980]

I did all of thise things, pump, thermostat, viscous fan, egr block and it was actually the radiator. Put a new one in and no more overheating. Took the top and bottom tanks off - nearly half the tubes blocked with some sort of grainy sand stuff. I was told that a 10 year vehicle would probably be a blocked rad.
Attached photo is of bottom tubes, they were nowhere as bad the top tubes.

Just had a chat to a friend yesterday and he told me the exact same thing. Replaced everything. Nothing helped. Had a wildlife crash a month later. Radiator got replaced. Problem solved. Will be my main way I guess. Update it here as soon as it's done.

Thanks already for all the input.