Normal temperature for 1fz-fe? (1 Viewer)

[zx350]

Hello I recently bought a 2009 71 series with 1fz-fe engine, in the summer when I stop and keep the engine running the temp gauge almost reaches the middle is that in the normal range,
and if it isn't in the normal range will replacing the original thermostat with a 1hz thermostat solve the problem,
And has anyone installed an aftermarket temp gauge and checked the actual temp versus the temp gauge.

 

[coldtaco]

you might check if there are different temp thermostat for your engine, instead of trying one from another engine unless you can verify that it will fit.
yes you can install a aftermarket water temp gauge, usually you can buy a adapter and install it in the top radiator hose. my experience with the 2H/12HT is that with the needle at the middle my temp is around 190-200F. anything above would be too warm. you need to learn where the needle sits and then when it shows something different then need to figure out what's going on.

 

[OGBeno]

you might check if there are different temp thermostat for your engine, instead of trying one from another engine unless you can verify that it will fit.
yes you can install a aftermarket water temp gauge, usually you can buy a adapter and install it in the top radiator hose. my experience with the 2H/12HT is that with the needle at the middle my temp is around 190-200F. anything above would be too warm. you need to learn where the needle sits and then when it shows something different then need to figure out what's going on.

Totally different with a gasser 1FZ.

 

[zx350]

also I live in a very hot climate and the needle only reaches the middle of the gauge in the summer and only in the day or when I go to the desert and rev it really hard while climbing some sand dunes, at night it stays at quarter of the gauge, and I am sure that the 1hz thermostat bolts on without any modification.

 

[JuanJ]

Hello,

The middle or below the middle is normal for a 1FZ engine.

Normal engine temperature is 83 C or 182 F. Under sustained load, or on a very hot day, it can reach 86 C or 187 F.

The numbers above correspond to middle or below the middle in the OEM temperature gauge.

You can replace the thermostat for peace of mind.

Engine oil with a little more viscosity is good for the engine you have. It does wonders to complement the cooling system and the thermostat. A good choice is Toyota OEM engine oil.

You can install an aftermarket temperature monitor. There are several options from Australian suppliers. One of them is Engine Watchdog.

Hope this helps.





Juan

 

[zx350]

Hello,

The middle or below the middle is normal for a 1FZ engine.

Normal engine temperature is 83 C or 182 F. Under sustained load, or on a very hot day, it can reach 86 C or 187 F.

The numbers above correspond to middle or below the middle in the OEM temperature gauge.

You can replace the thermostat for peace of mind.

Engine oil with a little more viscosity is good for the engine you have. It does wonders to complement the cooling system and the thermostat. A good choice is Toyota OEM engine oil.

You can install an aftermarket temperature monitor. There are several options from Australian suppliers. One of them is Engine Watchdog.

Hope this helps.





Juan

thanks, will installing the 1hz thermostat harm the engine by making it run cooler than normal.

 

[zx350]

Hello,

The middle or below the middle is normal for a 1FZ engine.

Normal engine temperature is 83 C or 182 F. Under sustained load, or on a very hot day, it can reach 86 C or 187 F.

The numbers above correspond to middle or below the middle in the OEM temperature gauge.

You can replace the thermostat for peace of mind.

Engine oil with a little more viscosity is good for the engine you have. It does wonders to complement the cooling system and the thermostat. A good choice is Toyota OEM engine oil.

You can install an aftermarket temperature monitor. There are several options from Australian suppliers. One of them is Engine Watchdog.

Hope this helps.





Juan

Also how did you know that 86 corresponds to the middle of the gauge

 

[JuanJ]

thanks, will installing the 1hz thermostat harm the engine by making it run cooler than normal.

Hello,

I would install the 1FZ thermostat, not the 1HZ. Remember that diesel engines, by design, run hotter than gasoline/petrol engines. A thermostat that operates at a slightly different temperature than the cooling system is designed for can complicate things.

The engine can run a bit cooler than normal with proper coolant and the right engine oil. Being a 2009, your engine needs oil with a little more viscosity than the one it has used so far.

Last but not least, make sure your radiator is in good shape.




Juan

 

[JuanJ]

Also how did you know that 86 corresponds to the middle of the gauge

Hello,

I measured the engine temperature (at the block and at the head, in several places) when it was hot after driving, and then I noticed where the gauge needle was.

That is how I know what the "normal" range is in the gauge.

I did this on normal days and during hot days. I even measured the temperature after oil changes, for reference.

The 1FZ engine cooling system is beefier than it looks. And you can trust the temperature gauge.





Juan

 

[Tennessee Jed]

June in Saudi Arabia is going to put any vehicle's needle in the middle, I would think.

The answer is always to repair and maintain your stock cooling system before going to measures like swapping thermostats from other engines, buying aftermarket radiators, etc. Simplistic answer but usually the right one.

 

[zx350]

Hello,

I would install the 1FZ thermostat. Remember that diesel engines, by design, run hotter than gasoline/petrol engines. A thermostat that operates at a slightly different temperature than the cooling system is designed for can complicate things.

The engine can run a bit cooler than normal with proper coolant and the right engine oil. Being a 2009, your engine needs oil with a little more viscosity than the one it has used so far.

Last but not least, make sure your radiator is in good shape.




Juan

Thanks for the information I was worried that it was overheating, as for the oil I am already running 20w-50

 

[zx350]

And one last question is it necessary to drain the coolant from the engine block drain plug in addition to the radiator drain plug because I am afraid that the workshops here will mess it up so will draining it from the radiator drain plug suffice.

 

[Tennessee Jed]

Gotta do both. This is actually one job I always pay to have done, partly because I completely trust our local mechanic, and partly because getting rid of used radiator coolant is nearly impossible here. There has to be a pretty good depth of expertise with Land Cruisers where you are, and at least a few reputable shops? Insist on Toyota coolant also.

 

[zx350]

Gotta do both. This is actually one job I always pay to have done, partly because I completely trust our local mechanic, and partly because getting rid of used radiator coolant is nearly impossible here. There has to be a pretty good depth of expertise with Land Cruisers where you are, and at least a few reputable shops? Insist on Toyota coolant also.

The problem is that nobody around here has heard of the second drain plug and if I haven't done the research I wouldn't have known about it.