vSAHARAx wrote:i would be fitting an aftermarket temp guage as well! the factory guages have a bloody big dead spot, and a few people i have talked to who own a 4.5 petrol say as soon as the temp guage has gone over the half way mark its blown a head gasket. Dont know if they were pulling my leg, but i do know the factory guage doesnt move off half way until around 115deg C
I actualy sell a digital temp gauge with a custom setable alarm for that exact reason which many people are installing on their LC 80's because of that exact problem described above.
The problem is your Toyota Temp Gauge has a
huge dead spot by design. I believe this is the case with a lot of cars actualy.
The issue with our 80's (especialy petrol ones) is that they traditionaly run quite hot and as the Toyota Temp Gauge on our dashboards doesn't move until it is often too late and usualy at least the head gasket is blown or worse a warped head etc. etc.. On other forums, our 80's are accused of having a weak head gasket as a result of the asbestos being removed from them and as a result the NEW oem replacements from Toyota are NOW metal.
The factory gauge will sit in the middle and not move from 155 degrees F(70 degrees C) through to about no less than 230 degrees F(110 degrees C)
So once you notice it move a needle width above half way - your Head Gasket is likely gone and it is usualy too late to cool the engine down before warping a head.... As you know, if you turn off an engine that is hot - the temp will actualy go up!
By having a temp gauge(especialy on with a settable alarm) - you can take corrective action earlier and you can also do something to fix a potential problem if you notice your temps are sitting higher than usual on the freeway for example - an early indicator of a problem like a blockage or a FAN Clutch on it's way out etc.
So given that there is little safety net, and a lot of us are using our 80's for what they were designed for (slow moving low rev work) I decided to install a digital temp gauge so that I can actualy see the temp moving (especialy since I tow a 2.5T boat) and I found a product that was perfect. It's small, has a nice and loud settable alarm and was very easy to install - takes a matter of minutes.
Basicly it is a digital thermocouple which tells you the temp of what ever you connect the wire to(in my case, I put it under the bolt holding the thermostat in place) and you set an alarm on it for what ever temp you want in celcius.
It has another wire that if you wanted to, could be hooked up to say the oil low light in the dash or any alarm light on the dash and it will act as an audible alarm for that as well.
The whole unit is
VERY EASY to install because you don't have to install extra sensors into radiator hoses etc. It's just a ring type connector on the end of the wire from the box which needs to be placed under a bolt where ever you want to measure the temp. ie. you could easily put it under a head bolt for instance. I wanted to know the temp off the thermostat - hence why I installed mine there....
I have since decided that the product is that good, that I would buy some into stock and sell them to other 80 owners (We also use them on our outboard motors as well)
$118 delivered anywhere in Australia which is still the lowest price for these anywhere - this is a very low cost insurance policy in my opinon that will give yourself a warning and some breathing space if your cooling system is on it's way out...
You can order them from http://www.fullwavemarine.com/tempgauge.html You can pay by Credit card via paypal or paypal direct.
From personal experience, I think this is one of the best safety gadget's we can install on our 80's given the apparently tempermental head gaskets and the fact that the factory temp guage has a dead spot that doesn't give you any warning until it's often too late....
Here is the blurb and some photos...
INEXPENSIVE ENGINE PROTECTION UNITS that will SAVE YOUR Car, Truck, Marine & Stationary Engine
Engine Protection Since 1982
Introducing the ENGINE WATCHDOG 'EASY FIT' electronic engine temperature sensor.
The 'EASY FIT' electronic temperature sensor can rapidly detect ALL ENGINE OVERHEATING caused by both COOLING SYSTEM or OIL SYSTEM FAILURES.
The sensor takes just seconds to fit under any convenient bolt that is near the heat source. By not breaking into the cooling system in any way you will not risk your engines warranty or longevity from faulty installation or electrolysis.
All Engine Watchdog models are supplied with the 'Easy Fit' engine temperature sensor.
Aftermarket Engine Temperature Gauge with a built in ((( Audible ))) Engine Overheating Alarm & Light.
Great value TEMPERATURE AND OIL protection for ALL Car, Truck & Marine Engines.
Engine Watchdog TM2 is an ideal aftermarket engine temperature gauge and audible overheating alarm, that will prevent premature and costly car engine replacement and engine rebuilds. The TM2 detects ALL car coolant system problems that are the causes of car engine overheating, including engine coolant leaks and heat build up from poor oil pressure. It will quickly warn you with a LED warning LIGHT and internal BUZZER if any abnormal engine overheating occurs long before it does damage.
The LED digital engine temperature gauge with its built in audible alarm mounts in the cab, while the 'Easy Fit' engine temperature sensor fits in seconds to the engine
Externally mounted, Very Loud Mini Sirens are available for noisy machinery, Siren must be ordered with the unit. Siren Price, plus $20 Aust.
TM2 comes complete with an installation kit and simple fitting and operational instructions. It suits 12 or 24 volt systems and is fully reverse polarity protected ( you won't blow it up).
To set the alarm, you simply read the highest car temperature on the display and then just set the alarm temperature a few degrees higher using the push button on the front panel. It simple and it works!
Wiring your TM2 to your existing OIL DASHBOARD WARNING LIGHT SENDER (not a oil gauge sensor), will make your oil light into an Audible Oil Pressure Warning Light . Should you lose engine oil pressure the buzzer will alarm. If you want this option and only have a gauge, you will need to fit an inexpensive car type oil pressure light sender to your engine.
Compact size ( less mounting tabs ) 80x30x60mm. ( 3.2" x 1.2" x 2.4" ) Standard lead length 4m ( 13ft ) or they may be ordered to size at no extra cost for boats and farm machinery. Max Temp 125C ( 255F )
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Here's the fitting instructions for anyone interested in how easy it is to install the sensor...
'EASY FIT'
TEMPERATURE SENSOR LOCATION
Mount the sensor in a convenient location where it will reflect the engine temperature correctly, or as near the heat source as possible. In this example we are monitoring the engine block temperature, so a tappet cover bolt has been chosen. To use the sensor as a engine cooling system monitor mount the sensor under a thermostat housing bolt.
The SENSOR HOLE size is 10mm ( 3/8")
Slip the heat sensor under the bolt and replace the bolt to its original position and tension.
IT'S THAT EASY! No possibility of car coolant leaks or electrolysis.
Secure the lead so there is no possibility it will be damaged, use the spiral wrap provided if required. If possible, avoid running the sensor lead right next to sparkplug leads, the coil or distributor.
