Chevrolet Bolt EV Traction Motor - Deep Dive

Evie, as you can see, this bearing seems to have some kind of gray layer on the outer race, while this one doesn't, and on the counter gear bearings they also have this gray layer. It doesn't say anything about what that gray layer is for. I suspect it is to prevent corrosion of dissimilar metals with possible induced currents passing through them with the vehicle moving on the road. I have seen this type of coating on universal joints on universal joint covers, universal joint covers, bearing covers on aluminum. aft drivesh of the same color. I don't know if it's the same material, but if any of you know what this coating is for, please put it in the comments below.

I'd appreciate it if you're just speculating, okay? I have moved the rotor out of the way. This is a useful piece. Now the last piece we need to remove is the stator assembly and it has three special guide pins that go into the stator

bolt

holes and screw into the transaxle case and then snap into place. tapered at the top here and that's to allow you to slide the stator out without it getting stuck in so I'm going to slide it over there and turn it down and just pull it out slightly here it comes like this so here's the stator for Chevrolet Eevee

bolt

.

If we zoom in and look at the stator windings, we can see that there are 1, 2, 3 rows of these fork conductors, which means there are 6 conductors

deep

in this stator and from what I read in the SAE document about this New improved

motor

, helps reduce AC power losses at higher

motor

rpm. A typical stator like in the previous Chevrolet Volt had 2 rows instead of 3, so there were four conductors

deep

in the Chevrolet Volts and six conductors deep here and one of the people who was on the original design team of the Chevrolet Volt told me that when they designed this electric motor and it is designed for maximum efficiency and manual power, there was no other motor that could match the efficiency of this motor and they said that they designed this motor. to be the next small block Chevrolet, so to speak, of powertrains, so the small block Chevrolet was and still is a very powerful and very popular V8 engine and has been for many years, and it was intended to have this engine design, maybe even this one.

The drive unit can be on multiple platforms with the same high power and high efficiency motor system. If we look at the other side of the stator windings, we can see the other end of the forked conductors and then there's a drip channel right here for the oil to come out. get out of that oil pan and drip and go down and lubricate the stator windings because they get very hot, this is the heat source inside the transmission and even though it gets hot, it doesn't get as hot as the fluid, even though the fluid gets hot. heats up, it doesn't heat up like a normal planetary gear style automatic transmission and the cooling system surge tank reservoir cap was only pressurized to 5 psi for this cooling system circuit, so lots of heat is generated much lower compared to an internal combustion engine. with a heat generating torque converter, automatic transmission style with planetary gear set.

Now just a couple of things to wrap up this disassembly video because we're going to put it back together showing the special measurements for the shims and everything when we get back together, but one thing I wanted. To show you about these electric vehicles is how simple they are and when I say simple I don't mean simple in design meaning it was easy to design this simplicity is not necessarily easy but if you look at the number of rotating parts. In this entire drive unit there are basically three main rotating parts. We have the rotor assembly that then turns the counter gear right here and then turns the final drive in three pieces.

No clutch packs, no bands or slippers, no roller clutches, no pistons, none of those hundreds of parts you'd see in a typical automatic transmission let alone the internal combustion engine this is replacing, of course there are three pieces main moving parts, these parts here, but each one has two bearings, so there are six more parts, so there are nine. in total and then inside the differential here we have two side gears and two differential pinion gears, making a total of 13 possible moving parts inside this drive unit and only when you are turning corners will the side gears in the differentials be turning at a different speed than the differential case, so these electric vehicles are a really basic and very reliable system, and this one is very efficient and the design is very compact as far as this left output shaft, remember, goes through center. of the rotor instead of being offset like in the Nissan Leaf and other electric vehicles, so congratulations to Chevrolet and the design team who created this incredible, efficient and simplistic Evie power unit and I think it is absolutely beautiful, so next I hope record a reassembly video with all the measurements of this drive unit and then we take out all these parts of the drive unit, all the electronics and our Chevy bolt and the one back here on the hoist are totally empty, yeah, underneath. the hood, so we have to put it all back together and get it running again, even if the battery is dead, everything is taken apart as far as the powertrain is concerned and we're going to put it back together and get it running. and hopefully convert it to DC fast charging.

Thanks for watching.