Thermostat Replacement Selection Considerations

[campbeam]

Many years ago, I had a thermostat failure and it remained closed resulting in a significantly increased temperature gauge reading. I have forgotten most of the details except that it was an '81 Honda Accord and the engine was not damaged. The quick workaround would have been to remove the thermostat then a visit to SuperCheap Auto.

Recently when I replaced the water pump, I am sure that I would have tested the thermostat [presumably original & 14 years old] before re-installing it. I am always considering possible efficiency gains and what is the best choice/recommendation for my particular vehicle and driving needs. Another major consideration is to avoid overheating and a possible blown head gasket. I started to consider what advantages or disadvantages there would be in having a thermostat with a low temp thermostat. Following internet article answered this question and I will be staying with the OEM temperature range [82C]. 

http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/

Next question was whether a high flow thermostat would be more beneficial compared to a standard thermostat. As it turned out to be, Tridon only supply the high flow thermostat TT281-180 for the Aurion [suits both 40 & 50 series]. On their website, Tridon makes the following statements: 

• The high flow thermostat is designed to interchange with the original thermostat. Utilizing a 30% larger opening valve, the high flow thermostat increases coolant flow and improves cooling system performance.
• Ideal for high performance applications, or for applications where additional loads are placed on the engine.

https://www.tridon.com.au/products/Tridon/35/479/thermostats-and-gaskets/528046/thermostat-high-flow

https://www.tridon.com.au/PartFinder/Toyota/Aurion/Any year

My most demanding application has been an interstate highway road trip with an outside temperature of 34C and the air-conditioning on its highest setting. I did not notice any increase in the temperature gauge reading so the cooling system must have been coping well enough.

The radiator is the other component in the cooling system under consideration for further research.

 

 

 

[Tony Prodigy]

Interesting article by tuner university Ash. There is always a lot of misconception surrounding some after market product companies and their claims to "improve efficiencies and performance". I usually take these with a grain of salt to be honest. Aftermarket manufacturers will always try to lure you their claims of higher performance. For what it's worth, I'd stick with Genuine Toyota Parts if I can get it first.

Engines are designed to operate at an optimal temperature and if you start fiddling with the setting you can set yourself up for failure. In the case of thermostats, these so called high flow, low flow items are just another avenue given to the ordinary punter to fiddle and potentially harm their engines. I have faith in what the engineers design and make for their factory vehicles and don't see the need to "up spec" as it were. If it ain't broken then why are you trying to fix it comes to mind.

If you try and make an engine run too cool, then it just accelerates wear. I'd keep it stock.

Probably the best time to replace the thermostat would be when doing the pump, and if you can afford it, also replace the ticking time bomb radiator too as part of the whole preventative maintenance routine. Time to also check the condition of the radiator hose and heater hoses too, especially if your getting up there in the Kays. A full coolant system refresh is the way to go for optimal reliability, rather than waiting for the next nearest component to go bad and have it all be out of sync.

Radiators and water pumps sometimes don't give any warning signs. If your lucky, you might hear the pump shaft bearing protest which can give someone early warning not to be complacent and get right on it, but radiators can just go pop anytime it feels like it. 

I'm going to start putting together a cooling system refresh kit myself just to be on the safe side. I have a pump, just need the rest.

[campbeam]

11 hours ago, Tony Prodigy said:

Aftermarket manufacturers will always try to lure you their claims of higher performance. For what it's worth, I'd stick with Genuine Toyota Parts if I can get it first.

Being price sensitive, I have a tendency to go aftermarket with OEM quality rather than pay a premium price for the genuine Toyota part.

In this case, the genuine Toyota thermostat was attractively priced and a premium was being charged for the aftermarket one. Ended up paying $35 [including postage] compared to $50.

https://www.ebay.com.au/itm/352852512978

https://www.supercheapauto.com.au/p/tridon-tridon-high-flow-thermostat---tt281-180/329356.html

Hopefully, it will sit in the parts box and not be needed for quite some time.