Help....inverter coolant not flowing even after pump change

Its an 09 Prius. Has 100K miles on it. I have in the past several weeks made three 350 mile trips, car ran perfectly. I have Techstream, and the car hasn't been setting any code except for an evaporative fuel system leak. It was time to do an inverter coolant change. I drained about 2 qts....that is all that would come out (and yes the bleeder valve was opened) Refilled it with Toyota SLLC. When topping off, using the procedure where you put a tube on the air bleeder valve and put the other end into the open reservoir), I notice that coolant would not rise up more than a couple of inches in the tube....bubbles came out, but it would never pump any fluid up into the reservoir, although the reservoir was about full. I then looked in the reservoir, and the coolant had not dropped an appreciable amount, and was absolutely still. Not the slightest ripple indicating flow. So I grounded the car and ordered a new pump (Gates brand) from Rock Auto. I should have thought about "how is it that it is going hundreds and hundreds of miles with no inverter coolant flow?" I guess.
Well, I installed new pump. Still have zero flow visible in reservoir, and never any fluid rising up in the bleeder tube, and the level in reservoir never drops! I did hear a very loud noise from the new pump after hitting the start button twice to make it run, this lasted only about 1 or two seconds, and thereafter it was quiet....like abnormally quiet, no funny sounds of air in system or anything....but it is definitely running, there is a quiet smooth sound and you can feel the vibrations.So I drained coolant again (this time oddly only 1 qt drained out). I removed the new pump intending to determine if either the old or new pumps are pumping or not, as it seems like there is a blockage in the system. Wish I had a pressure gauge to see what is happening on the discharge side, whichever it is.
I looked up this system in the Bentley manual, and it has one short paragraph and one illustration of the system....It covers the earlier generation only through 2008 unfortunately, so I am uncertain as to whether significant changes to the inverter cooling system were made in 2009. But from the diagram, there is no valve to control the flow at all., no valve that could possibly be closed.
This appears to be a simple centrifugal pump, which means it should not be damaged by a discharge blockage. I need to operational test these pumps. I put two sections of tubing on the old one, and (guessing) put one end in a tub of water. It pumped no water with either of the two pipes on the pump submerged in the tub. Then it occurred to me that its not going to pump unless the suction side is primed.....have to figure out some way to do that. But I am not even sure which is discharge and which suction.
I also thought about the possibility of an air lock, the pump not working before it was uninstalled, due to no prime. I think it must have been full of fluid, as I could squeeze either hose right next to it, and the level in the bleeder tube would go up and down a little. It also stays very quiet as I said, not starting to make a loud racket from bearings running dry.

Can I test it for a blockage by forcing some compressed air into the pump tubing, with reservoir cap and bleeder closed??? Is safe?

I also would like to know if the car will shut down with the triangle of death with an overtemp of inverter or MG1/ MG2? Or just set codes for same, or problem with coolant flow or temp?

Update to my first post.....I got new pump tested operationally, and it's not really running at all. After I installed it, I sure THOUGHT it was running but it didn't turn at all during the operational pumping check, and after that I checked with an ohm meter and it reads up in the megs with either polarity! Will probably never deal with Rock Auto again, but their parts have always been reliable and good in the past. Needed this car fixed badly, now it will be days longer. Now I am wondering if the original pump died thousands of miles ago! Because I read elsewhere in this forum that even if no coolant is being pumped, the car continues to operate sometimes for a long time nevertheless...until the car gets particularly stressed on a hot day.
I think the original pump was not really the original....I know there was a defect in the 09 inv. coolant pumps, and Toyota replaced them under a "recall" or something. I bought the car at 50K miles, 50K miles ago. Well, the mechanic who did this replacement--- or SOME replacement--- believe it or not, had cut both power wires a few inches from the pump....when I peeled off the ordinary junk cheap black electricians' tape, the mechanic had just stripped the ends of the copper wire and twisted them together, then taped them No boutt splice or solder! Of course the wires were corroding. But not so badly yet that there was a bad connection, dropping voltage. Still....what kind of idiot would do this with a vital electrical component which has to work to prevent failure of a 2000.00 electrical component? They did wire it up with black to black and white to white, so reversed voltage wasn't a cause of failure (connector will only go on one way, the right way)

 

Actually its not a power problem at all. My #2 RockAuto pump was installed today, and STILL there was not the slightest flow watching for ripples in coolant tank. I even put a drop of food coloring in there, and confirmed no flow. I could hear and feel new pump seemingly running fine and pretty quiet.So I took off the bleeder vent entirely, and no coolant came out at all. So I pulled both pump hoses off to see if there was any coolant. There was none! I got two hoses and put them on in place of the actual inlet and outlet hoses. Poured some water in to the suction (top) of pump and I could see it was pumping some. I stopped pouring water and put my thumb over the end of the hose, and it developed a vacuum. So....it's not pumping at all because its air-locked....no coolant is getting through to the suction side of the pump, its all full of air, and so the pump is just cavitating. I pumped some shop air in to both the inlet and outlet hoses to the
coolant pump, and I got lots of air and coolant out either way....that is, when I had the reservoir cap on and the fill plug tight.
So if I can just figure out some way to get rid of the huge amount of air that is left in the system, then it will work!
I am thinking that I need to get the discharge hose (going to the top/suction inlet on the pump) vented and/or where I can also pour in some coolant. This is the hose that has some slack in it, and runs right along the top front of engine bay, before turning into the Inverter discharge port. Easy to get to. This I could do with a DuPont radiator flush tee. But other people are apparently getting their inv. coolant system drained and refilled without resorting to that...what am I missing????

 

Now I recall that the very first time I removed the original pump, or the pump that's been in there since I got it, I thought it odd that my clamps on inlet and discharge were not necessary, as I found that releasing the clamps did not result in the reservoir draining or any leakage of fluid. Filling the system , it only takes about 2 qts. On this Prius, the reservoir does not go to the pump at all, it goes to the right and connects up to the inv. coolant radiator on the bottom right side of car. The actual hose that goes into the top of the pump (comes down vertical to pump after a 90 degree bend)--- that hose goes to upper RH front on the inverter, which must be discharge, as it is going to the inlet of pump. But I hardly think anyone has done creative re-routing of the cooling system, it has driven for for 50K miles and three very hot summers like this.
There is no kink that I can see. Maybe there is still a partial blockage, but as I said I was able to blow shop air through either hose on the water pump, with the reservoir cap and fill plug on. I blow air through the inlet, and it comes forcefully out the discharge and vic versa. It could have been not flowing for thousands of miles, as I only just learned that you have to look in the reservoir to see if you have flow through it. But I can only see one hose going into it....so how is there going to be a flow through it? Must be another hose going to it that is concealed underneath? .

 

Bingo. Indeed those two lines are reversed. Funny because I was looking at the flow diagram in my Bentley manual and according to it, it's correct . but if you are sure your diagram is the correct one I will swap them amd see what happens. The pump inlet hose is not going to the hose on reservoir, it is going straight to a port on upper inverter! I always checked the level in reservoir for the 50 k miles I have had it. So this error was made by some mechanic within first 50k miles. Unless the factory did it? I guess there must be considerable cooling even if it's not circulating!

 

Well, I thought sure that reversing the lines would fix it.....but no. First I drained the system of all that would come out. I filled up the reservoir and this time it was full with about 1 qt.! So I got my Little Giant vacuum squeeze-pump and connected it up to the bleeder valve. I pumped and pumped, and it sucked a ton of air out allowing me to put a lot more coolant in the reservoir. Started coolant pump running. The water was absolutely still in reservoir, no flow, and level never dropped. Also the bleeder valve was loosened, and then taken out completely, no coolant and /or bubble came out. So I turned off car. then pulled off discharge hose on side of pump. Water ( really I am just using water for now) came pouring out, emptying reservoir in a couple of seconds. No blockage there on that discharge hose, and the suction side of pump is definitely being primed/filled with water now (sure wasn't before) by gravity.... it's downhill from the reservoir. To see if there was a free flow of water through transaxle and inverter, I stuck a long-neck funnel into the end of the discharge hose ( that had been pulled off the reservoir). I plugged the hole left in the reservoir with a piece of rubber glove and rubber bands. Held funnel up high to give it some head pressure, and poured in water from gallon jug. In a short time, the transaxle/inverter filed up, and started to fill the reservoir. It made a glug-glug noise from all the air bubble escaping at the rear of the reservoir. Definitely no blockage there, either. I then went one step further and turned coolant pump back on. and began quickly pouring in more water into the funnel and discharge hose. All of a sudden, the pump came to life and i had lots of water spilling out the open reservoir and water coming out the bleeder valve tube also. When I stopped pouring water and put my thumb over the end of discharge tube, it built up a pretty good vacuum. So the pump is pumping . So then I thought, the only place left for there to be a blockage is the inverter coolant radiator. So I reconnected the pump discharge hose to the reservoir. Then to test for a blocked radiator, I pulled the short section of hose on left of radiator off where it connects to transaxle. Then I pulled off the long section of hose coming from the RH side of the radiator. (the hose I swapped with the pump discharge hose) This hose is now connected to fitting at upper RH of inverter. I stuck my shop air gun into the end of it with piece of cloth to seal it.... .air with high pressure came out the other end, out of the LH short radiator hose. So there is definitely no blockage in the inverter coolant radiator either. It would seem that I have covered all possibilities. I am about ready to pull my hair our, what could I be missing!
If I can't fix it soon, then I have no choice but to have it towed 50 miles to Toyota Nation dealer, no one else within 150 miles will touch a Prius. The tow alone will run about 150.00. And this crooked overpriced dealership will rob the shirt off your back.....,would have to take out a loan to pay the bill most likely.
Actually the Bentley Prius manual I have only covers to 2008....so maybe a coolant hose routing change was made in 2009, and that is why the flow diagram is different from the flow diagram you gave a link to.

 

I read elsewhere in this forum that the 09 Prius will set a code on inverter coolant overheat....is that right? Hope so, as It has only generated one fault code about evaporative fuel system minor leak in all the miles I have put on it.

 

Sorry I wasn't clear. When the hose (which is really the discharge hose...from the pump) was pulled off pump, water flowed freely out of the pump! That's why i said that it proves that this hose coming off the reservoir, the suction hose for the pump, is not blocked, and pump must have been full of water. The same hose, which I had pulled off the front of reservoir which goes down to the suction on pump is what I was referring to, its really discharge you could say from reservoir, but suction hose for the pump. I verified that I have 12V on the black wire, and the white wire is negative. When I redid the connections of course I kept black to black and white to white, And the connector is keyed so that it cannot go on backwards--- plus as i said the pump is building up a vacuum when I plugged that SUCTION hose pulled off the front of reservoir with my thumb. So the pump is turning in a way that builds up suction on the hose connection that comes up vertical from teh pump. the discharge from pump is horizontal, and goes downward. Will it even turn both ways?

 

I checked that water was flowing freely from reservoir and out the nipple on the transaxle to which is connected the short hose to LH side of radiator. Yes It was. With that short hose disconnected, I blew some shop air into first the nipple on transaxle, which resulted in lots of air and water shooting out of reservoir and bleeder, and then I blew air into the disconnected hose as well, and again lots of water/air from reservoir and bleeder. This tests pretty much the whole system for blockage. So I connected everything back up and refilled . Started pump and it seems to be pumping some coolant now. So thanks everyone for your help!