2001 Prius Inverter Pump

The part number for the inverter coolant pump is:
G9020-47022

 

That's for the revised pump. As previously explained, the pump was redesigned for better durability.

The simplest solution would be to upgrade the pump and be done with it.

 

Thanks!

I sent an Ebay note to the seller and asked if we can do an exchange. I also notice another 'heater pump' being listed as an inverter pump. Oh well, such things happen.

Bob Wilson

 

replacing the inverter should do it

 

Replacing the inverter coolant pump is ~$100. Replacing the inverter is nearly an order of magnitude higher.

Bob Wilson

 

I've bought what should be an inverter pump, the part number matches. Hopefully it will be here next week.

Meanwhile, it occurs to me that if the thermostat were removed, the heater pump might be able to handle the ICE cooling needs and eliminate the mechanical pump. A variable bypass valve might be needed to avoid the radiator, the thermistat substitute. The goal being to maintain a specific ICE coolant temperature and engage the radiator only as needed when extra cooling is needed.

Bob Wilson

 

Interesting idea - a sort of variable radiator system driven by electric pump, probably would get hot faster for winter when the radiator is off.

BTW I still have that inquiry to the flow sensor manufacturer concerning - "coolants exposure" question. It says water and some chemicals so it probably will do fine.

Also did you get the gen1 inv. water pump yet? I'm looking at one on eBay new in box for $109 + shipping of course. It will be good for experiments with the sensors, using the old coolant I will change out of the car soon. I already did the transaxle oil (which was good -no problems) but not the coolant yet. It probably needs it anyway after 8 years ..
Let me know because soon I will act on these items soon.

 

It arrived today.

I'm going to buy some hose and make a water loop to test it tomorrow. Once I have the voltage and current, most of my questions will be answered. Initial testing with a VOM show show no measurable resistance suggesting electronic controller. Using the diode test, it conducted in only one direction, confirming an electronic controller.

I notice there is a flat plate on the bottom with three small vents. The plate has a ridge so it looks like it may 'snap in'. I tried to use a flat to pry it out but there is no give. Regardless, I'm very curious as to what the inside looks like.

Photos are coming.

No competition from me. <grins>

My next procurement is a ZVW30 pump so I can do pressure tests.

Bob Wilson

 

Real good Bob,
Concerning "Using the diode test, it conducted in only one direction, confirming an electronic controller." I think that is why in the manual it stresses "do not hook up power backwards" as well.
Ok then I will go ahead and get the pump I had my eye on, and then after experimenting etc. w/sensors is done, it will hopefully become a good spare for the 03' too.

 

The gen1 inv. pump and the flow sensors are on their way. Sensors are coming from Israel but it looks like from feedback it is a pretty quick ship. Verified inv. pump is new and is for 00-03, that should get here first. Here's to keeping our fingers crossed. If the sensor doesn't work well in this environment well at least I'll have a brand new spare pump.
Will update any future results.

 

When the pump arrives, you'll find the W3 connector has two little slots on one side, the B+, pin 2. The round side is pin 1, ground. But one caution, make sure your 12 V power supply is well regulated.


I used my MRC 989 in power supply mode but it acts as if it is constant current, not constant voltage. I stated at 0.8 A. and it seemed to be working although I was seeing voltages running as low as 9 V. So I upped the current and after about a minute, it stopped. But I think it is the MRC 989.

I changed to a 12 V, 500 ma., wall wart and it is showing ~0.38-0.39 A. at 12.3 V, 'air' load. Using a junk box, step-up transformer connected to headphones, I could distinctly hear the current modulation as well as feel the unit vibration. So it looks like we're good to go for phase II, getting a new, ZVW30 inverter pump and working out the interfaces.

I really hate the vibration of the NHW11 pump. An impeller pump, it should have no vibration. I'm hoping the ZVW30 pump is better balanced. At least it has two bearings.

Bob Wilson

 

Hey Bob, were you pumping water through those hoses? It looks pretty clear like maybe there is no water yet. I'm sure the pump would be louder when dry, and quiet down (dampen) when water is pumped w/no air. Ok on the power, I will be using a variable 5-18V /30A bench dc supply that is normally on the radio bench, so it's definitely well regulated. So you're going to try sensing the current to the motor and develop a warning system if the pump should stop correct? The back EMF should kick the indicated voltage higher, but I agree that the average current reading will be different running vs. stopped. Also the speed or frequency of the emf spikes you hear would I would think be faster when running in air only load. BTW I don't know how good it is to run the pump in air, it probably gets a portion of it's cooling from the liquid coolant (or water) as well.

 

In the photo, I had tap water. But when the MRC 989 acted up, I drained and took the 5/8" ID hose off. I wasn't sure if it was pump or power supply so I tried the wall wart.

I haven't gone back to the water loop, yet. Right now I'm planning on ordering a ZVW30 pump so I can start doing A-B testing.

That is my thinking. What is a hoot is my 'transformer' is a toroidal choke with three loops of hook-up wire that I had in my junk box. I suspect I can wire up a bridge to a cap and easily light a LED. But I really need to quantify what I'm seeing.

I figured the ~2 W wouldn't hurt for the short time I was testing. I'm not sure about what the actual signal looked like so let's hold off on that. I suspect it is a brushless motor given the earlier diode testing. Any back EMF might be clamped in the controller.

Bob Wilson

 

"What is a hoot is my 'transformer' is a toroidal choke with three loops of hook-up wire"
Oh yes I'm fully aware of how a transformer can be quickly devised, and with the toroid core you can just run the wire you're monitoring through it as well thus not disrupting the circuit being measured.
The flow approach will not disrupt the original circuit either, but may restrict fluid flow just a bit. We'll see, but you know there really is no system function I can find that tests for flow, only temp. There is a temp sensor on the farside of the inv. radiator that I presume is used to monitor when it's too hot (going up a long 50mi. hill etc). But that sensor would see a reduced temp with no flow.. assuming the vehicle is moving and has airflow on the radiator, and the inv. temp sensors would climb really fast. I would think that with current draw during driving that would be enough to trigger
a warning, but nooo.

 

The ZVW30 inverter pump, G9040-48020, is on the way, $154.89 plus shipping. With luck, it'll be here next week and I'll get a chance to see how to adapt it to our NHW11.

My current water pump is working perfectly fine but I'm after the improved design. With luck, the pipe nipples will be the same size or easily adaptable. Get the drive worked out and it'll be time for the replacement.

Bob Wilson

 

Ok, here is the series:






The OD of the nipples match. There are likely to be some fitting challenges and of course the electronics but . . .

Bob Wilson

 

That pump looks superior indeed, and it looks like you can take it apart to some extent without destroying it. No flow sensors here yet but they did ship them, coming from Israel. I'm all ready for experimentation on them and an original gen1 pump. Stay tuned.

 

Ok I got the flow sensors and have begun testing with regular antifreeze using the gen1 inv. pump. Here is a picture of it flowing. Notice the ohmmeter shorted.

 

And here it is with the pump shut off -NO flow. Notice ohmmeter is "open" It is very repeatable.
BTW I tested where the impeller stalls and that is exactly at 8.9V very repeatable, if the voltage drops below 8.9V there is still a buzzing noise from pump, but there definitely is NO flow even with the noise, and as soon as it rises above 8.9V there is flow again. I ran it with no fluid and the pump was very loud until I got solid liquid flow then it settles down and is again quiet. So it looks like a winner but I'll keep it in this setup for a while and see if the sensor has any problems with time in coolant.

 

Oh I forgot to mention that it draws exactly 1.5A @ 12V from my well regulated power supply when flowing. Have never seen higher than this value, it seems however that when it stops flowing the current is less (~.5A) , however I had to reduce voltage to the 8.9V level to stall the impeller and stop the flow. Who knows what the current would be if the impeller stopped while it's at 12V?

In this shot you can also see this is my spare NiMh battery bench.
I have a couple three modules that are perfect candidates for the re-hydration experiment. Soon I will drill the 6 holes in those modules and add the boiling water etc. They just don't hold a charge for very long anymore. I suspect they were sitting outside in a junkyard for at least a year.
But that's for another thread..