1HDT Heat issue? (1 Viewer)

[DBWood]

I have a '90 1HDT 160km's. Owned it for 2.5 years now, but living on a small island never got to travel more than 10-20 miles at a time.
Now I have it back in Canada and actually getting to drive it!
After about 45 minutes of driving at highway speed (80-90kmh) it starts to heat up a little. I am used to it running just under the halfway mark on the factory heat gauge, but now it will climb to about 2/3's. At which point I take it easy for a while and it cools off.
So, is that the normal range, and I have never gotten it to operating temp before? OR, have I got an issue with the rad, or the turbo getting hot?

I know, I need a proper heat gauge. It is on the list.....

Thanks for any input.

Doug

 

[gbentink]

No, its not normal, the needle should almost never move once it has settled to normal opertaing temp. That point on the gauge may varry from gauge to gauge, vehicle to vehicle but the point is it should not fluctutae much after having warmed up.

Even if driving short periods, it should still warm up if the thermostat is working. It can take a while though, diesels (DI) take alot longer to warm up that petrol engines.

Sounds to me like your thermostat is about to fail, having partially failed already.

Or of course your radiator needs an overhaul. This is easy (ish) to check by observing the temps of the water coming from the radiator into the engine. If radiator is failing, temps will be very high.

Any pressure in cooling system (head gasket)?. This is highly unlikely, but anythings possible. An excellnt way to check a head gasket leak is check for cooling system pressure when engine is running but cold. I open radiator cap when cold to relieve pressure difference to atmosphere, replace it. Start the engine and run it for a while, especially with some load if you can. Then squeeze the top radiator hose with your hand, it shouldnt be really tight if engines still cool.

Cheers, Graeme

I have a '90 1HDT 160km's. Owned it for 2.5 years now, but living on a small island never got to travel more than 10-20 miles at a time.
Now I have it back in Canada and actually getting to drive it!
After about 45 minutes of driving at highway speed (80-90kmh) it starts to heat up a little. I am used to it running just under the halfway mark on the factory heat gauge, but now it will climb to about 2/3's. At which point I take it easy for a while and it cools off.
So, is that the normal range, and I have never gotten it to operating temp before? OR, have I got an issue with the rad, or the turbo getting hot?

I know, I need a proper heat gauge. It is on the list.....

Thanks for any input.

Doug

 

[finderscuba]

Or your coolant could simply be too low...

 

[BCR4619]

Or your fan clutch is shot.........

Too Many Or's untill you give us more info like coolant level and so on...

With your truck off cam you spin your fan clutch with you finger fairly easily or does it stop right away?

Cheers

 

[Tapage]

1. during HW driving the fan clutch does not make that difference in temps ..

2. take a reliable water temp gauge and certify the temps ..

3. it's there any good amount of black smoke . ?

4. Auto or manual tranny .. ?

 

[BCR4619]

1. during HW driving the fan clutch does not make that difference in temps QUOTE]

Whoops, should have known that, with the amount of air at 90km/h why would it even matter

 

[DBWood]

Thanks guys.

I had to pull the alternator out yesterday. Hopefully the shop can rebuild it for me....

So, I have not been that worried about the temp issue!

BCR, it will idle all day and maintain temp. So, I don't think it is the clutch.

Tapage, Only a little smoke on hard acceleration and initial cold start up. Normal?

Graeme, it is quite possible that it is the (original) rad, or the thermostat. I will try your method when I get it running again. IF the rad was failing, would it still idle for a long period without overheating?

Keep in mind, I am not a mechanic, and the rig has not seen a "Real" mechanic in about 15 years. I will be getting it into see someone more qualified than me in the near future. Life has been hectic, with moving (Sorry Tapage, I ditched my beautiful beach for Canada!) and getting all the other stuff sorted out...

Thanks guys.

Doug

 

[Tapage]

I would start with basic simple and cheap stuff .. rad cap .. !

 

[DBWood]

I would start with basic simple and cheap stuff .. rad cap .. !

Lol. Yes, the rad cap is about 6 months old....

 

[Radd Cruisers]

1. during HW driving the fan clutch does not make that difference in temps QUOTE]

Whoops, should have known that, with the amount of air at 90km/h why would it even matter

The fan clutch doing nothing on the highway is a MYTH !! It does absolutely add to the cooling.

If the vehicle is a JDM, then you have about a 95% chance that the cooling system is in poor shape, the rad is plugged, the hoses are original etc...

Go through your system progressively. Overheating can be as simple as a bad rad cap, to a really badly adjusted injection pump that is over-fueling.

~John

 

[BCR4619]

Interesting, I didn't think it would with the amount of air but I guess if it's running hot it would try and take in more air. I gotta look into one more then, not too sure how they exactly work.

Sent from my iPhone using IH8MUD

 

[Kalawang]

Interesting problem.

The only time I had temperature problems was when my thermostat rusted out. Whereas I live in a tropical place, I solved the problem by removing it. However this is such a simple solution I would expect you to have already looked into that.


Kalawang

 

[DBWood]

Interesting problem.

The only time I had temperature problems was when my thermostat rusted out. Whereas I live in a tropical place, I solved the problem by removing it. However this is such a simple solution I would expect you to have already looked into that.


Kalawang

I guess since I just moved the truck from the Caribbean, I should look at the thermostat then....

Thanks for all the input guys.

Radd is spot on. I need to go through the whole cooling system and replace some parts.

Anyone have any 1HDT parts for sale? Radd?...