How to choose a good used transaxle. Ideas?

There is no external test point although there is Toyota proprietary test cable. You really have to take the case off and there is a significant risk in that. Whatever you do, don't try to go through the main cable insulation. The traction battery is isolated from the frame and there are three, safety relays.

The only sensible way is to remove the traction battery and put it on a bench. Personally, I would hold off until you have a scanner and manuals.

You've diagnosed the failure ... nothing to learn from an oil sample.

Bob Wilson

 

Sorry, I forgot to mention the ground fault interruption system. If the resistance to ground of either side of the traction battery falls below several megaohms, it takes power off of the three safety relays to isolate the traction battery on each end and breaks the middle. The system is so sensitive that an electrolyte leak will trip it. You never want to do anything to compromise the insulation and I believe the main power cables are shielded.

A photo of the pan would help but I can imagine someone driving over a curb or rock in such a way as to loosen and start to unscrew the plug. Once loosened, the oil would leak out and vibration would cause the plug to unscrew and drop off. Loss of oil and the rest is burnt toast.

Bob Wilson

 

is it possible to buy used transaxle including the seller's warranty for some valuable time period in USA ?

 

Usually a salvage part has a very limited time warranty, like one week. The buyer is basically assuming the risk of failure.

For example, see:
http://cgi.ebay.com/ebaymotors/TOYO...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

 

Ok, I'm going to suggest a couple of sensible precautions and why:

1. Flush the transaxle - it has probably been in different orientations and that means the accumulated gunk has had a chance to wander into places it should not be. Hobbit found a 'plug' at the top of the NHW20 transaxle and there may be one on the NHW11. Assume filthy, wretched previous vehicle oil has sloshed about. Try to flush out as much of the old stuff as possible without stressing the assembled unit.
2. Drop the pan and wipe all exposed parts throughly - this will also give you a chance to look for 'bad stuff' in the sump. There is a small nook to the rear that the differential gear is in that can barely be reached via a small, finger sized galley hole. Be creative!
3. Careful about foreign lubricants - straight kerosene might be OK for a flush oil but it has not been tested. If you use it, you are the newest, junior Prius, materials engineer. This might be a place where parts from the failed transaxle may give a clue. Either OEM Type T-IV or Type WS transaxle oils are known to be safe.
4. Clean, clean, clean, clean ... Oh did I mention clean?
5. Last chance to check the oil pump ... be sure to have a set of gaskets.

My high mileage transaxle appears to shed small bits of the silicon sealant that I've found in the pan. It looks like pinkish plastic bits.

GOOD LUCK!
Bob Wilson

 

Checkout Tom's photos from swapping the transaxle. He has shown exactly what needs to be done and it is so simple:

1. Remove inverter and stuff on top
2. Lift car front
3. Remove steering assembly
4. Remove wheels and axles
5. Put dolly under transaxle
6. Loosen and drop down

Much easier than the whole engine assembly!

Bob Wilson

 

Yes, that would be a great buy as long as it really is from a Classic and not 2G as was the case with the other transaxles offered to you.

There were only 53K Classic shipped to the US. My guess is that Canada might have 5K or fewer of that model. So it may not be easy (or cheap) to obtain good salvage parts...

 

Uh oh. You may want to drop the glove compartment and pull out the cabin air filter. Stuff from the cowl goes down the air inlet and is stopped by the cabin filter.

Bob Wilson

 

The three windings are "wye-connected", therefore a winding-to-frame short in any of the three windings will show a fault, as a fault in X will also show as a fault in Y and Z, just as a fault in Y will also show as a fault in X and Z, just as a fault in Z will also show as a fault in X and Y.

The resistances to frame will be different in each case, of course, but all three will show a Hi-Pot test failure.

MG1 and MG2 should both be Hi-Pot tested, although if anticipating a replacement of just one of those, then just that one may be Hi-Pot tested to save a little time.