Coolant Service Question

how much extra to replace the thermo?

 

1. I don't think it's necessary to change the thermostat unless there's a problem or you are already at over 150k miles.
2. The system doesn't need to be "flushed", just drain and fill. Make sure he uses Toyota Super Long Life Coolant (pink stuff). If you flush the system with water, the water will be stuck in there and dilute the Super Long Life Coolant (already a premixed formula, shouldn't add water)
3. You will maybe need a total of 2 - 3 gallons of coolant if you are doing the entire Engine and Inverter coolant loops.

It's very important to get all the air out of the system when doing the coolant changes, especially in the Las Vegas heat.

 

I think "flushes", where you continuously run water through, our going out of fashion. For a couple of reasons:

1. It complicates recycling of the used coolant. Unless it's just dumped down a sanitary or storm sewer, which isn't good.
2. the water lingers in the lines and dilutes the already premixed new coolant, which is bad news.

(JC91006 has pretty much addressed all of this, just to chime in.)

Also, I'm thinking along same lines as bisco, I think. Thermostats have rubber that can fray, and they're open/close points can go off. Cheap insurance to change it while they're in there.

 

20 bucks on ebay.

 

You really do not need a coolant flush and as previously stated, the introduction of substantial water into the system will just dilute the premixed Toyota Super Long Life Coolant.

My post shows the engine thermostat location:
How to replace engine coolant pump and thermostat | PriusChat

 

Lets not forget likely flushed with municipal tap water (lots of minerals). I don't know of any shop that uses distilled water when flushing the cooling system.

 

Don't do it. I'm at 350,000+ same coolant I had at 150,000 same t-stat too. Do it when u replace the hoses.


iPhone ?

 

No the ICE coolant system is not connected to the Inverter cooling system. They do share the radiator in separate tanks though. I highly recommend you have the Inverter coolant changed also. The car is very easy on the ICE coolant but rather hard on the Inverter coolant.
Take care of the Inverter its the most important and hardest working part in the car. Inverter coolant change is very easy unlike the ICE.

Btw keep a close eye on the ICE coolant level for a few days as it will settle and may require topping off. Its almost impossible to get all the air out when it is bled. Do this by checking it at the radiator cap itself when the motor is cool by taking off the top black plastic rad cover.
The overflow tank may give you false reading of capacity till all the air in the system has evaporated. Use your heater too for a bit as that will
completely circulate the coolant.

 

I've read this many times that Inverter coolant is worked harder than the ICE's.

Anyone know the normal operating temps for the ICE coolant -vs- Inverter coolant???

 

I found the thermostat to be THE most annoying part to reach of all the maintenance I have performed on the G2 Prius, but Pat Wong seemed to manage the job without much drama. So the question is, are you more like me, or Pat ?

 

My study showed on my car about 100-110 degree's for Inverter and about 190 for ICE.
But has major heat soak issue since there in the same rad only different compartments. Minute you shut the car off the Inverter coolant spikes about 20-30 higher. Quite fast.

But the temperature is not whats so hard on the Inverter coolant its the metal the coolant see's. It's pure aluminum in the heat sink cross section and the trans cooling section. Huge cross section on the Invert heatsink.
Very corrosive and hard on the fluid. And in turn hard on the pump. Changing the inverter coolant is very very easy and it will extend Inverter and Inverter pump life. I try to do it every 30K miles. Major difference in bottle turbulence with new fluid compared to old.

Just like changing the ICE coolant will help extend the water pump also. ICE is a real pain though. Did a change once never again. I just dump the rad every year or so. No airlock.

 

thanks!!!