Thermostat 1KZ-TE engine

Typical after 5 years of almost problem free Townace driving, I have the Hiace just over a week and the thermostat has died.

The Mrs wanted the heater on so I slide the slider over a little on the climate control, a few moments later she asks have I turned it on so I move it some more. check vents and it is warm but not hot, look at temp gauge an it is at the third block in (about a 1/4 if you don't have the digital meter).
Oh bother I think, head gasket empty wallet syndrome. Pull over ( and why do things happen at night in the rain?). Check water and oil all ok, so not overheating but underheating. Check fan and it moves freely so not locked up.
Guess it is the thermostat stuck open.

Ordered one from Toyota arrives just intime for the predicted icy weather in the UK!

Any one done one? Can I reach it through the wheel arch or does the driver floor need to come up, if so how do I do that?

Even the radiator bunches don't like doing it on a 3 ltr turbo as it is under the turbo and you have to do a fair bit of work to get at it.

Have fun, this is where you keep telling yourself "but it is a top thing to drive "

And the manual just says undo the three bolts on the housing and remove the thermostat, which is fine if the engine is out!

Not had look but if it is under the turbo maybe I can get to it from underneath?

Not that fussed about a heater, but if it is stuck open I guess it could work lose and get stuck closed?

Not from underneath, cross member in the way, nor through wheel arch, so it is a floor out job.
I think once there removing the alternator should give enough room for it.
Going to wait for another job that needs doing under there before I try it

The way I did mine (KZH106) was through the driver side wheel arch.
remove the wheel and then unclip the rubber shroud. Its a tight job and patience is required. So, in order-
1. Drain coolant by dropping the bottom hose. You can access the bottom radiator hose clip from underneath the vehicle.
2. Remove driver wheel and unclip rubber shroud.
3. Undo the three bolts holding the aluminium water inlet branch.
4. Replace the thermostat and gasket and reassemble.

Hope this helps!

Had a look that way and could only see half of one of the three bolts. Is yours a 4WD?

Guess what temp back to normal this morning.

I found a few drips at the front of the crossmember so I think the pump gasket and/or the pump is weeping so the floor will have to come out, guess what I'm doing over Christmas! Had planned to do the timing belt and drive belts anyway.
Just priced the pump Blueprint £140.00 inc VAT, Toyota £119.99 ex VAT but including gasket set.

I need a thermostat in mine too. It warms up slowly in cool weather but is ok in warm weather and on the motorway. I guess that's about as good as it can be for a failure of a part :~) I'll fix it one day. I imagine my RWD will be a little easier than fixing an AWD?

Got to look at mag wheels next. Can't stand the horrid rolly boat cornering on the 70 series tyres and will look at 60 series on 16" rims.

It should reduce the involuntary lane change in wind.

The steering tracking can make quite a difference to the straight line stability too.

alfazar wrote:

The steering tracking can make quite a difference to the straight line stability too.

Yep, wheel alignment coming soon, now that I have wheels and 45 series sports tyres on.

The van steers great, is far more stable on the motorway and corners surprisingly flat. The 70 series tyres were so much at fault for the driveability issues. Wet and dry traction has improved markedly. The slightly reduced diameter also allows it to accelerate a little more aggresively .

Back on topic, my thermostat has not gotten any worse and the engine remains quite drivable with it stuck open in warm weather. We have about 93,000 Km on ours now and I figure at 100K the belts need doing, so I'll get the thermostat at that point too. I don't relish doing anything under there in the van. Cars are so much easier to work on, but the convenience of the van is fantastic.

Dwayne wrote:

The way I did mine (KZH106) was through the driver side wheel arch.
remove the wheel and then unclip the rubber shroud. Its a tight job and patience is required. So, in order-
1. Drain coolant by dropping the bottom hose. You can access the bottom radiator hose clip from underneath the vehicle.
2. Remove driver wheel and unclip rubber shroud.
3. Undo the three bolts holding the aluminium water inlet branch.
4. Replace the thermostat and gasket and reassemble.

Hope this helps!

Yeah spot on! just in the middle of doing this now and yes its a tight job, but got the sucker out. I ordered a new thermostat based on the Hilux listing with the same 1kZTE from my local auto shop, hope this is in the right temp range - the opening temprature stamped on the original is 76 deg - i tested it and it starts to open at 85 and only stays open a small amount - opens fully only when it reaches about 98 deg. I figure this is the problem? I was over heating - only loosing coolant through the over pressure valve - kept having to top it up with water all the time to keep her cool.

I must see if that works with the 2wd one day.. glad it worked for you mate

Cheers i would think its the same as the 2wd, total mission of a job though finished it off this arvo and all is well no more over heating! The only thing thats puzzling me now is all my warrning lights on the dash wont turn off when the motor is running - i have a feeling that its somthing to do with forgetting to plug in the wires on the alternator as they were in the way when i removed the thermostat, i only pluged it back in after i had the engine running and now lights only go off when you turn the ignition off, tried disconnecting the battery and checked all fuses but warrning lights still stay on????????

Greetings to all!

srburnsy, did you ever fix the all-lights-on problem?

Me, new boy on the block (spend most of my time on Surf forum - LN130 with 2LT-E). Just bought the SC for my son and thought better learn about 1kz quick & smart!

ciao

lm

Welcome mate, another Aussie
I think this covers how to reset warning lights

Code:

 http://hiace-super-custom.forumotion.com/members-guides-to-fixing-problems-f8/engine-managment-fault-codes-and-how-to-read-them-t439.htm

AussieQ,

Ital-aussie actually, on lifetime resident visa, compliments of Malcom Fraser..!

What I think srburnsy was talking about is all or some of the lights at bottom of the dash, i.e. the symptom of a sick alternator, me think...

Ah, and for members who might not be aware, there's heaps of good info and stuff on 2L-T, TE, 3L, 1KZ-TE and more on the Aussie Surf forum Toyotasurf.asn.au

lm

Welcome mate.

Yeah all that ended up being was a blown alternator fuse , i found it in the battery compartment.

Hay just updating on this thread... When i replaced my thermostat last year with an aftermarket one it had a opening temp of 88 degrees stamped on it compared to the original one which had 76 degrees on it? And ever since then i have noticed that my temp gauge rises above the halfway when going up long hills? which it never did before? Thought this was bit odd so did a bit of research and found that there is a 71 degree thermostat for our 1KZTE that is better suited and could be good for anyone with cooling problems? Anyway found info on it on the Surf forum. http://dahn.webcity.com.au/~toy49040/forum/viewtopic.php?t=8049&highlight=

Thanks mate good info