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I am working on my 96 Corolla Coupler. I checked with the usual suppliers (CanEV, EV West...) they do not have a coupler and motor adapter for my 1996 Corolla. Yes, I checked the bolt pattern and they do not match. I am planning on keeping the stock clutch. (If you do not agree please be respectful and do not comment such as "I don't know why you would want to do that." "I would be easier if you go clutchless" "Why do you need a transmission anyway" etc... So this is what I dd. I cut off the end of my crankshaft where it mounts to the flywheel and where the clutch assembly is mounted. It was easier then I thought started first by using a 4' grinding wheel finished the job with a reciprocating saw. I took it to my local machinist and he bored out the AC motor shaft size and keyway. The collar is a 4140 prehardened chrome moly steel.
 

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Pretty smart actually! Gives you a mechanical fuse basically to the transmission and driveline.

Want to do similar to my 88 samurai so I can get the most out of the motor depending on the situation, like low gears for off roading, mid gears for around town and high gears for highway and passing.
 

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my mind is blowing the clutch before you nuke the transmission or snap the ujoints/cvs course nobody is gonna be slamming the gas petal down every time they want to go cause tire traction issues come up at that point.
 

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my mind is blowing the clutch before you nuke the transmission or snap the ujoints/cvs course nobody is gonna be slamming the gas petal down every time they want to go cause tire traction issues come up at that point.
Ah... you're thinking of the clutch slipping as the "fuse". (y)
The novel thing about ToyXCAB89's coupler is using the end of a crankshaft as the basis for a coupler, not the idea of using a clutch; using a clutch is very common (and until recently was almost the universal design).

In practice, tire traction is typically the torque limitation, not failure of any driveline component.
 

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You can rig a mechanical fuse.

We had a shear bolt on our Massey hay baler (bolt that goes through both the coupler and shaft, no keyway, and the coupler was a greased fit 😂) - seems it would always shear if you got in too much of a hurry trying to beat the incoming weather, resetting time back to what it would have taken just going slow and steady, it seems.

Nonetheless, we kept a box of shear bolts around, lol, because weekend farmers don't get to pick their days to bale hay.
 

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Unless the shear pin is really soft or 1/16" diameter, you'll break something else in the powertrain or ruin the tires before the pin fails. Then you have to pull the engine or trans to replace the pin.
 

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I did something very similar with an 87 jeep YJ conversion cause wasn't ready to do 2 motors/adapter, all the EXPERTS said your going to break A,B,C that was back in 15, well 30,000 miles, 5 islands and a volcano, and the only thing broke were 33" tires wearing out from the mass of 1.21 gigawatts, I did install a second motor, front and rear wheel drive, but your idea is great, unless you bring your knee to your chest and GRANDIZER kick the go pedal every time, your not going to lunch box anything, great build!
 

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I started with a cut off crank end, as well, but when I had an insert welded into the end of it to mate up with the motor, the shop welded it in crooked. I ended up turning an entirely new piece out of a steel on my little lathe. That was "fun". I haven't made it to the welding step again but I am taking precatuions to make sure it doesn't end up crooked again.

B
 

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Kudos ToyXCAB89. I did something very similar with a BMW conversion. Went a slightly different approach, and rather than drill out the crankshaft flange to slip over the motor shaft (which I think is a great idea), instead left a "stub" off of it that turned-down to the same diameter of the motor shaft, and then used a shaft coupler. The attached picture sort of shows it. In the end, it worked very well. Took some time to get the balancing right though. When you want to use a clutch (which in many cases, I do agree is still a good idea), and you're running out of options for an off-the-shelf adapter/coupler, it is pretty good approach. You just need a good machinist to get that crankshaft end done right.
 

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Cejota3,
I think that this was one of my first thoughts.
How did you do it? How is it attached?
Not sure if you can tell from the pic I posted, but basically I've got a "coupler" that seems to be like that one your holding in that picture. A "double clamp", "keyed" type. I could track down the model # and where I bought it on another day if someone really needs to know.
The backside of the crankshaft flange/stub I used I had lathed down to the same diameter as the electric motor shaft (basically the last main bearing portion of the crankshaft) and then had it "keyed" as well. I don't have any other good pictures of it at the moment.
I found that double-clamping coupler really helped keep it steady, because as I said in the first post, I had some "balancing challenges" at first (a whole other story) that kept on loosening the other couplers I tried, for example those that just had a single set screw.
I also had "z-axis" issues, basically the pressing force when the clutch was engaged (think pressing the clutch pedal) creates a lot of force pressing against that coupler towards the motor. So inside that coupler, between the motor shaft and the stub shaft off of my coupler, I had to add some spacers. Looking at your pictures, it seems like that might be something you have to deal with also, but kind of tough to tell for sure.
 

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Not sure if you can tell from the pic I posted, but basically I've got a "coupler" that seems to be like that one your holding in that picture. A "double clamp", "keyed" type. I could track down the model # and where I bought it on another day if someone really needs to know.
The backside of the crankshaft flange/stub I used I had lathed down to the same diameter as the electric motor shaft (basically the last main bearing portion of the crankshaft) and then had it "keyed" as well. I don't have any other good pictures of it at the moment.
I found that double-clamping coupler really helped keep it steady, because as I said in the first post, I had some "balancing challenges" at first (a whole other story) that kept on loosening the other couplers I tried, for example those that just had a single set screw.
I also had "z-axis" issues, basically the pressing force when the clutch was engaged (think pressing the clutch pedal) creates a lot of force pressing against that coupler towards the motor. So inside that coupler, between the motor shaft and the stub shaft off of my coupler, I had to add some spacers. Looking at your pictures, it seems like that might be something you have to deal with also, but kind of tough to tell for sure.
Oh, I guess I'm missing an important part. I also "sliced" off the back of the engine block that the crankshaft came from, had that milled flat, and then devised a way to have that mount to my motor, and then of course, that "adapter plate" naturally connected perfectly to the tranny bell housing (because it used to be the back of the engine that would connect to it). Here is a picture that shows it mocked-up a bit before I had it all dialed it. It's not shown in this picture, but the crankshaft "adapter" would then just sit where it normally would. Got rid of the RMS (real main seal) because you obviously no longer need that.
(I'm actually on vacation at the moment, without access to a lot of the pictures that would better show all of this!)
 

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