Changing Inverter Coolant With Airlift.

I think you'll find that 2G inverter coolant can be easily replaced and the system purged of air, without the use of an Airlift.

 

I think Assenmacher makes an adapter, possibly the one in the link below but I'm not sure, but I have found that the conical one works fine.

ASSENMACHER AST Toyota Special Adaptor Mr2 Tundra, Celica, Gt-S Yr. 2000 - NHProEquip.com

 

Simply opening the bleeder screw and keeping the reservoir full while car is in ready allows pump to run and is accomplished in minutes. No special tools are required. Run a clear plastic tube from nipple to reservoir and watch the bubbles! It's a BLAST!

 

Although the ICE is a bit more difficult to bleed, opening the Allan wrench to the right of the radiator when facing the front of the car, makes a huge difference! I think it is 6mm metric. You have to search a bit for this air bleed screw, it is close to the top. Do no quote me but I believe from 2007 on, the thermos idea was dropped. Search on PC for the facts on that. There is a auto idle function that you can use, I never did actually get it, but instead entered some other mode of non-continuous idle ( the idle would cycle ) which in fact accomplished my goal of bleeding air from the ICE anyway. As for bleeding the inverter that is absolute simplicity, just attach clear tubing from bleeder screw to reservoir, OPEN bleeder screw, put car in ready, AND watch bubbles coming out. After a few seconds bubbles will stop and you are finished ! One important point on ICE: open up heater controls to circulate that air as well. Look at Pat Wongs sticky.

 

I don't think I have ever heard of or read anywhere someone complaining that the AirLift doesn't work well or is not worth the money. You do need an air compressor, which is the only downside. The special adapter is probably overkill, but it is something that a busy shop would easily justify.

On the other hand, I have read countless stories of people struggling to get cooling loops bled (not just Prius by any stretch), and Gen IIs leaving the dealership after pump repairs only code later with airlocked inverter or ICE cooling loops.

 

Yes, it would be helpful on all 2G Prius when replacing engine coolant.

 

Although very easy to hand bleed the Inverter, with an Airlift it goes from a 15 minute hand bleed job job to a 2 minute 100% garanteed air lock free job. And I do mean 2 minutes.

They work great. You just need an air compressor.

 

For those who have an Airlift tool or are trying to decide if it is worth buying before changing your inverter coolant - I give it two thumbs up! Changed my inverter coolant today using the Airlift tool and decided to document it since I didn't see a clear description given yet (other than it's faster and easier - which it is). I know now from experience that it's very straight-forward but I would've felt more confident going into it with a few pictures and descriptions so decided to offer my experience to this conversation. As Seilerts indicated the conical adapter is less than ideal but works fine if one is careful not to move it too much when disconnecting compressed air hose and reconnecting the suction tube for drawing coolant in - the high vacuum helps to hold it in.

Bought the Airlift kit from Amazon.com for just over $100, it looks solidly made and comes in a nice carrying case. See pictures below.

Pic#1 - Included is gauge/adapter body (left of center), vacuum venturi (left), fluid fill tube w/ filter screen (right) & rubber adapter rings for various reservoir neck sizes.

Pic#2 - To do the inverter coolant change I used the conical adapter shown.

Had car up on ramps already to change PSD fluid, seemed like a good time to get this done too. Noticed reservoir cap had pink residue that looked powdery or gritty - rinsed it & blew it off, cleaned up nicely. After removing drain plug and finding granulated white substance in it & in reservoir I decided to flush system out w/ water (water in Portland OR is very clean, close to bottled water, but may do 2nd change after few hundred miles if ya'll at PC strongly recommend it). After draining coolant I removed bleed screw in front of inverter and flushed water down reservoir, flushed down bleed port and flushed up from drain hole until it came out the top - then let it drain completely again. I could have blown system out w/ air hose or let air dry but was running out of daylight.

Pic#3 - Removing Coolant drain plug.

Pic#4 - White residue in drain plug (had more but dumped some out before I noticed it).

Reinstalled drain plug and bleed screw. pushed Airlift conical adapter firmly into reservoir, twisting back and forth slightly. Attached air hose and vacuum dropped below 25" quite rapidly - had small compressor that had trouble keeping up w/ air flow so I shut off valve until compressor reached full pressure and then opened & shut it again at maximum vacuum (around 27").

Pic#5 - Airlift in place on inverter coolant reservoir w/ compressed air hose (connected at lower left) & venturii attached to gauge assembly, red valve handle is open allowing air to be drawn from inverter cooling system. Compressed air and air drawn from cooling system is blown out clear tube to right.

Removed venturii unit from gauge assembly and waited for 5 minutes to verify no air leaks. Picture shows 25" because I forgot to take another picture after I let the compressor build full pressure and evacuated again.

Pic#6 - Red valve handle turned off & venturii removed - if vacuum gauge holds steady your system is leak-free!

Airlift instructions say that refill fluid should be at or near the level of the Airlift device - everything under the Prius hood seems to be a sloping surface but found a stable place leaning on the right fender.

Pic#7 - Coolant fill tube connected w/ pickup screen in jug of SLLC - when gauge valve is opened coolant will be drawn from jug into system.

After the reservoir level showed full I still had about 10" of vacuum left. I left the Airlift attached but valve off, put the car in "Ready" mode to run the coolant pump - unfortunately the engine started, not really a problem except it makes it harder to hear the coolant pump. After running a few seconds the coolant level dropped about 1/2". Opened fill valve again and fluid reached full mark just as vacuum was fully depleted. I turned off valve on fill hose but left gauge valve open and disconnected fill line from gauge assembly - remaining fluid in gauge body drained into reservoir. I raised fill tube valve high above jug of SLLC and opened it to drain remaining coolant from tube back into jug. The hood latch made a nice spot to hang the valve handle to let tube drain completely.

Pic#8 - Convenient place to hang fill tube to drain remaining fluid in line back into jug.

I don't know how accurate the marks are on the jug of SLLC but according to the marks I used just a tiny bit over 2qts - maybe 2.1qt.

The "hardest" part on this job was reading all the posts on PC to make sure I wasn't missing something. I don't mind the reading though, I always learn more than I expect reading through the posts. With the Airlift tool it was easier than changing the oil - hmm could it work with engine oil...nah, probably not.

Hope this gives future DIYers confidence that they can easily do this job themselves and save money. Of course I spent most of my savings on the Airlift tool, but w/ multiple cars and a motorcycle I'm sure I'll have many other uses for it.

 

Raqune,

Thanks for the write up and pix.

It appears that those folks who have installed a front shock tower brace
will have to remove the brace to get the Airlift adapter to fit squarely
in the coolant reservoir filler neck. There is only ~3/4" clearance between
the brace bar and filler cap.

It should't be a big a deal; just remove the bolts at either end of the
brace bar that secures the bar to the mounting brackets.

Here's my tower brace installation, I believe that it is typical:

 

Ragune,

Thanks for the write-up and pictures. I have been looking at the Airlift device as my car is coming up on the need to change both the inverter and ICE coolant.

I know now that I will be purchasing an Airlift device in the near future.

Dwight

 

Nice work and writeup.

I suggest you make the car IG-ON (not READY) if you wish to hear the inverter coolant pump running, to confirm that no air remains in the system.

It is pretty easy to change the inverter coolant without use of this tool, but the tool will be very helpful when you replace the engine coolant and try to refill the CHRS canister.

 

Nice write up.

I got mine at Amazon too. The price refused to drop on eBay unless you wanted one missing adapters. I'm getting ready to do the engine coolant and I have used an airlift before and its the only way to fly.

I too noticed the powdery stuff on the cap. Even after an Inverter coolant FLUSH (with clean water) and replacement the powder quickly came back. I believe that's aluminum salts coming off the Inverter heat sink. Aluminum corrosion. Which can contaminate the coolant pretty quick. And I bet is really hard on the coolant pump seals. And kills coolant heat transfer.

If you want to improve your mileage instantly change your Inverter coolant.

The Prius is unique because I bet the aluminum there using for the Inverter heatsink which the coolant cool's is pure aluminum for best heat transfer. Problem with that is pure aluminum is very corrosive so you need a really
good anti corrosive package in the coolant your using. I don't believe Toyota SLLC is that great in that dept.

I have been using this product in my Inverter coolant tank. Half a bottle.
The Inverter runs cooler and the powder has not returned. Its a very good auto anti corrosive additive. I have been using this for 20 years in every car I have owned since then and have never needed radiator service and the interior of the radiators using this product is very impressive.

Red Line Synthetic Oil - WaterWetter® Coolant Additives - WaterWetter®

Available at most auto parts stores.

 

I just got my Airlift 550000 device from Amazon last night. $101. Matco, the vendor, lists this 550000 as $176.00. Ebay was around $150+.

Thanks Ragune

 

I just changed my engine and inverter coolant yesterday using the new Airlift device. This is definitely the way to go. It was almost too easy.

Even with the engine coolant I may have had to add 1/2" of coolant to the reservoir after running engine and heater. No entrained air issues at all.

The inverter coolant was even easier.

Even using the universal wedge fitting in the resevoirs, and even with the weight of the different hoses pulling it to one side, there was no problem maintaining the vacuum.

One good thing that I learned from removing the entire engine undercover is that even for oil and filter changes I will remove the engine undercover rather than just dropping the oil change door. It is just so much easier to get to everything and you can just do a much better visual inspection of the entire underside.