Re: [electricboats] Coolant Recommendations

The system is not intended to be pressurized.  Simple loop.  Now that I think about it though I suppose with heat buildup it could build up pressure without a vent.  It more or less follows the plan outlined in this document from Thunderstruck:
http://www.thunderstruck-ev.com/images/companies/1/CoolingNotes2021.pdf?1612471899962

Attached photos shows the components as installed.  Heat exchanger is at lower left.   Blue hose is coolant to motor/controller, red is return from motor/controller.  Large bronze pump is raw water pump (it is louder than motor!).  Coolant pump is just below raw water pump.  It is a pump from a Prius.

The coolant pump is switched by a relay controlled by the Sevcon controller.  It turns on at 50C and off at 40C. 


Thanks, Dan

 

On 2021-07-20 9:54 pm, Carsten via groups.io wrote:

 

Dan, is your system closed, (can be pressurized), or open ?

What is the temperature when cooling circulation (the pump) starts ?

 

 

On Wednesday, 21 July 2021, 10:47:36 GMT+8, Matthew Geier <matthew@sleeper.apana.org.au> wrote:

 

 

I help look after a 1997 built light rail vehicle that has water cooled traction converters and motors. The manufacture of the vehicle recommends anti-freeze, and not just to stop the coolant freezing. (Although that is a consideration in some regions).  Not only does it contain corrosion inhibitors, it changes the boiling point of the coolant so it can run hotter (ie over 100 degrees C) with out needing to be under pressure. This allows the otherwise low pressure system to remove more heat.

There is actually a table in our ops manual showing how the concentration of the recommended coolant additive (The coolant is mostly distilled water) affects the boiling point.

On 21/7/21 11:41 am, Carsten via groups.io wrote:

Hi Dan,

 

As I recall, you are living in a warm place ?

 

Distilled (not purified) water will be fine, and it cools better than any special liquids will.

Distilled water contains no ions to make corrosion possible.

It will not prevent freezing, of course.

 

You can even tap it right from your aircon drain at home (if it is clean).

Boil it before use for desinfection.

 

I guess "waterless" does not mean "ion-less", so I do not know the performance of the special products when combining copper and aluminum.

Consult your dealer for product specs, if you trust him.

 

Cheers,

Carsten

 

 

On Wednesday, 21 July 2021, 02:57:50 GMT+8, Dan Pfeiffer <dan@pfeiffer.net> wrote:

 

 

I am ready to fill my cooling system with coolant.  The controller cooler has a copper tubing and the motor is aluminum.  Hoses are PVC and the heat exchanger is copper+aluminum.   Any specific recommendations for coolant out there?   Anything to stay away from? 

I found this list on a search for coolant for aluminum motors:
https://motorcareguys.com/best-antifreeze-for-aluminium-engines/

The water-less coolant may be interesting? 

Seems there is no point in trying to be frugal when the whole system will take about 2 liters.  If I have to mix the coolant with water I will use distilled water. 

Thanks, Dan Pfeiffer