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My plan is to have 2 torque bars that run back from the motor mounts and bolt to the adapter plate (where the 2 bolts are inserted in the image). The motor will then rest in a cradle that spans between the torque bars.
It looks like you have some aftermarket universal ICE motor mounts. Rather than use these, maybe a simpler way to mount the front of the transmission to the frame, is to use the existing angled frame mounts either side of the bell housing. You could make a simple, one piece flat plate cross member that picks up at least 2 of the transmission face bolts. Or, a 2 piece, flat plate mount (one on each side of the bell housing) that picks up at least 2 bolts each side. These mount(s) could be attached to forward extending flat bar pieces bolted to the existing angled frame mounts. You should include some gusseting where the plate(s) and bars meet, for additional strength.

Even if you wanted to include some anti-vibration rubber elements in this alternative design, it probably would be less work and a cleaner build than trying to use the ICE motor mounts.

I'm not quite sure what you mean by resting the motor in a cradle. The motor has a very stout face mount that is designed to support the weight and torque of the motor. I'm assuming the CANEV adapter plate is likewise stout enough.
 

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I agree that the motor doesn't likely need a cradle - it can just be supported from the drive face - but the motor and the front of the transmission need to be supported by something, so some sort of framework extending on each side to the stock engine mount locations makes sense to me. The stock engine mounts appear to be at the crossmember (where the new brackets are shown), but there are visible mounting points further back on the frame - what are those for, and could they be used instead?
 

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Discussion Starter · #63 ·
Well, I made a little progress today, but I am afraid I am going to have to try again (although not from the beginning I hope). This should hopefully make things a little more clear:

The 1"x1/8" flat bars that span the two torque arms are just there temporarily to hold the two halves in alignment. I decided to try and base my alignment off the tires, so I put a string between the front and back tires and used that as a reference point. It seems that the driveline is centered. The frame is really irregular at the end of the trans due to the way the crossmember supporting it is mounted. I tried to use a plumb bob to get things aligned to the tire line, but... It was not ideal.

Looking at the hole in the "center" of the front cross member in the photo, it appears I am pretty far out of whack. Measuring from the center top of the tires also shows that the forward end of the transmission is indeed too far to the left. The tires are pretty easy to measure off of- would they be an acceptable reference point?

The stock engine mounts appear to be at the crossmember (where the new brackets are shown), but there are visible mounting points further back on the frame
Yeah, the new brackets use the same bolt holes from the original engine mounts. Getting the aftermarket kit just seemed like it would be easier to fabricate (also I threw away the engine-side of the mounts during the de-ICEing, oops). The holes you see in about the plane of the bellhousing are just holes drilled in the little strut that holds one end of the lower control arm for the front suspension. There was nothing bolted on there in the original configuration, and the clearance to the bellhousing is pretty tight.

It would probably be fine to do a solid mount from back there, but I kinda want to try and keep the whole motor and trans floating on rubber dampers. As for the motor cradle, Its main function is going to be keeping the torque arms in position, but also to support the weight of the motor a little bit. If the motor was cantilevered, every bump in the road would put strain on the mounting bolts. I am sure they would be able to handle it, but it seems like cheap insurance to include it.
 

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... I decided to try and base my alignment off the tires, so I put a string between the front and back tires and used that as a reference point. It seems that the driveline is centered. The frame is really irregular at the end of the trans due to the way the crossmember supporting it is mounted. I tried to use a plumb bob to get things aligned to the tire line, but... It was not ideal.

Looking at the hole in the "center" of the front cross member in the photo, it appears I am pretty far out of whack. Measuring from the center top of the tires also shows that the forward end of the transmission is indeed too far to the left. The tires are pretty easy to measure off of- would they be an acceptable reference point?
That does look way off of centre, judging by anything... like the "engine" mounts, or any of the frame features where the mounts are installed.

Hub faces (with the tires and wheels removed) are easier to use precisely than the tires. Suspension mounting points t the frame might be better than anything at the hub end of the suspension, just because moving parts might not be in exactly the same position (ride height) on the left and right sides.

Houses are built now using laser levels which can be set to project a vertical plane - it might be easier to measure horizontally (using a level) from the laser plane to vehicle features, rather than using string lines and a plumb bob. I haven't tried it - just a suggestion.

The holes you see in about the plane of the bellhousing are just holes drilled in the little strut that holds one end of the lower control arm for the front suspension. There was nothing bolted on there in the original configuration, and the clearance to the bellhousing is pretty tight.

It would probably be fine to do a solid mount from back there, but I kinda want to try and keep the whole motor and trans floating on rubber dampers. As for the motor cradle, Its main function is going to be keeping the torque arms in position, but also to support the weight of the motor a little bit. If the motor was cantilevered, every bump in the road would put strain on the mounting bolts. I am sure they would be able to handle it, but it seems like cheap insurance to include it.
Thanks - that makes sense. :) Although there was nothing supported on top of those brackets, they would work structurally... but that doesn't matter if they're too far back.

I'm sure that the motor and transmission should be supported on compliant mounts. Of course those mounts need to take the entire transmission output torque, so they need to be widely separated and stiff enough, as those mounts are.

Supporting anything from multiple points can be tricky, as you might add bending stress that you are trying to avoid. The cradle is rigidly mounted to the assembly at the adapter - which is fine - so perhaps any support by the cradle near the front of the motor should be compliant. What does the motor manufacturer say about support?
 

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Discussion Starter · #65 ·
Alright, nice weather has been keeping me busy outside, but I managed to get a bit of time in the shop to straighten out the mess that was my first attempt at the motor mounts....

This time I centered the shaft off the frame rails just ahead of those struts for the control arms. The measurements off the tires agreed within an eight of and inch, so I am hoping it is close enough to not cause problems. With the angle meter I at least got the transmission sitting level, and the angle on the trans output is within a tenth of a degree of the diff input end. The overall working angle of the driveshaft joints appears to be about 2.5 degree.

I am having to do some fiddling to get the mounting tabs to line up right, as the engine mounts are out of alignment both front-to-back and side-to-side (this was also the case with the original ICE mounts). I got the first half tacked in place, and I just need to check that I have clearance to my motor before continuing. Redoing work is a hassle, but when you start out knowing nothing about how to proceed, mistakes are bound to be made :).

Supporting anything from multiple points can be tricky, as you might add bending stress that you are trying to avoid. The cradle is rigidly mounted to the assembly at the adapter - which is fine - so perhaps any support by the cradle near the front of the motor should be compliant. What does the motor manufacturer say about support?
I have not really asked the guys at netgain about motor support, but if I ask them to check my work, I will post their response. My thinking is that I want the finished unit to behave as closely as possible to the ICE equivalent. Basically, that means I want to have motor and trans bolted and secured as a single assembly, and resting on 3 compliant points. I think cradling the encoder end of the motor near the mounting feet will make this whole assembly into a very rigid unit. There is also going to be a shelf above the motor to hold the controller and such, and I will probably overbuild that to give the whole unit more resistance to twisting forces. I am also planning on gusseting the point where the square tube meets the flat stock at the adapter plate.
 

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My thinking is that I want the finished unit to behave as closely as possible to the ICE equivalent. Basically, that means I want to have motor and trans bolted and secured as a single assembly, and resting on 3 compliant points. I think cradling the encoder end of the motor near the mounting feet will make this whole assembly into a very rigid unit.
All that is great - it makes a lot of sense. It's just the idea of attaching the motor to the rest of that assembly at both the mounting face and another location that concerns me.
 

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O-C, your concerns may have some justification, the more I think about this set-up. A cantilevered structure, such as the face mounted motor, has a greater chance of generating undesirable harmonic vibration by itself and perhaps amplifying vibrations from other componants-like the drive line. Some kind of adjusable resilient mount supporting the outer end of the motor, that doesn't put bad side loads on the motor and adapter plate(to address brian's concerns), might reduce this problem. Keep going, you're on the right track.
 

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Discussion Starter · #68 ·
It's just the idea of attaching the motor to the rest of that assembly at both the mounting face and another location that concerns me.
I think I get what you are driving at, as connecting the motor at both ends will make it behave like a beam, and put compressive and tensile stress on the motor casing? I am starting to wonder though if I am maybe overthinking how much force will actually act on the motor.
 

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I think I get what you are driving at, as connecting the motor at both ends will make it behave like a beam, and put compressive and tensile stress on the motor casing?
Right... and while the motor case is intended to support the motor, who knows what will happen when bolted to a transmission and a long structure tying the parts together. It's probably not big deal, but it would be unfortunate to create a problem while trying to solve another one which might not even exist.
 

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Discussion Starter · #70 ·
Ok, got a little more done on my engine mount today.


Its hard to see from this angle, but I gusseted the front connection point and built a sturdy frame that holds the two torque arms together. The 1-1/2" angle iron on top is drilled and tapped for the mounting shelf/shelves. I might make the shelf for the controller out of aluminum, and put some fins on the bottom or something for heat transfer. I had an old 12v radiator fan in my junk pile, so I made mounting brackets so it will sit on the front and blow air over the motor and under the controller.

I do not have the right tools, so the curved motor cradle is going to take a lot of fiddly work. I basically cut a band of 16ga sheet to follow the shape of the motor, and then tacked on a bent 1"x1/8" flat bar. I had at first thought I would weld this directly to the torque arms, but I like your thought of having it be at least somewhat adjustable, electro wrks.


I am thinking it could bolt through tabs on the arms, and have a little play top and bottom for some washers or shims or something. I could even add rubber blocks instead if I decide not to go with a rigid mount.

With as overbuilt as this unit has become, I am not too worried about putting stress on the motor. The trans itself is not that heavy, and I am confident that my torque arms will be up to the task of supporting it. I sent a request to netgain for some input, but didnt hear anything back yet.
 

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This design would work. 3/16"-1/4" X 1 1/2" flat bar would be enough. Above 3/16" thickness, FB this size is pretty tough to bend without a stout vice and hammer, and usually a torch. A shop with a roller could form it for you. Or, in a scrap yard, you may find a short piece of pipe with a diameter close to the motor. Cut the band to width with cut-off grinding wheels. Adjust the diameter for a proper fit. Weld on pre-drilled tabs.
 

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Discussion Starter · #73 ·
A shop with a roller could form it for you.
If I was going to do this again, that is the route I would have gone. My attempt at using what was on hand was a real shit-show. I ended up doing a lot of grinding and hammering to get the stupid bottom band to fit. The heat from welding it was enough to warp it just slightly, but I think I managed to get it sorted out well enough. I was feeling pretty done with it, and just slapped on a thin band over the top. It should be enough to keep it in place. Since the band is not part of the structure, it could be replaced down the road without having to pull the engine.



I got it all cleaned up and ready to paint:



Next up is sort of a big step - its time to mount the hub and flywheel and get the motor and trans hooked together. I am a little nervous about seating the hub as it is shrink-fit to the shaft. The instructions say to heat it to 400F in the oven for an hour, then tap it onto the shaft with a wooden block and a hammer. Also, should I remove the pilot shaft bushing before heating it up?
 

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Discussion Starter · #75 ·
Pictures of the hub, the transmission input shaft, the motor shaft, and the bearing?
I will take some pictures when I am at the shop next. I am also going to look around and see if anyone documented a similar install on an old thread. I am not sure how I would screw it up, but I dont want to have to try and get the hub back off if something is not right on the first try...
 

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Discussion Starter · #76 ·
Well $%#@ me. What should have been a breeze is turning into a nightmare. Here is the setup.

I popped the pilot shaft bushing out to be on the safe side, and then I heated up the hub as instructed. I rushed out to the shop with it wrapped in towels, put the key in place and it simply dropped right into place. Only one problem - the key was too $%&*ing long! The instructions did not mention that it might need to be trimmed, and it did not even occur to me that the parts I got would not simply work the way they were. So the hub is now locked in place, but riding about a quarter of an inch too high. I have tried a 3 jaw puller, and applying heat to the hub, but it is stuck on there as though welded in place.

I did check the runout, as I needed to do something to keep from taking a hammer and smashing half the stuff in my shop - and at least that is spot on. About 1.5 thousandths. The motor shaft was within a quarter of one thousandth.

Anyway, I am going to try calling around tomorrow and see if I can find a shop that might have the tools and know-how to get this thing back off again. Any thoughts on where I would even start looking?

I did manage to wrestle the trans out, and the paint job on my cradle turned out okay, so once this bullshit is straightened out, things will go together pretty quick.
 

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Did you try carefully tapping the key down into the key ways? Or, do you know for sure it is too long? If it is, you probably could reach in with a squared end carbide burr in a die grinder and carve away the key to make room for the bushing or bearing.

Ok. I reread your post. You're in trouble! Probably more heat and a bigger puller are what's needed. CanEV switched to this type of hub because customers had trouble working with the much more convenient (in my opinion) tapered bushing type hubs.
 

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Discussion Starter · #78 ·
I am quite sure it is too long. When placed in the groove on the shaft it protruded beyond the end. If I had been thinking critically, this should have raised red flags. I assumed the keyway was cut the whole way through on the hub, which it is not. Looking down the hole for the pilot shaft bearing I can see the protruding tip of the key, and the gap between the end of the shaft and bottom of the pilot shaft bearing hole. I did try tapping it down while it was still hot, and it didnt go anywhere.

There is no way I am going to be able to grind it out from the top. I could maybe drill it out from the side, but that would leave a big hole in the side of the hub. I think it has to come off.
 

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A repair shop with a medium to large H frame press should be able to press the shaft and motor out of the hub. Don't forget to have a pile or box of rags and drop clothes to catch the motor as it falls away!
 

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Discussion Starter · #80 ·
I took the motor in to an electric motor shop, and they popped the hub off as easy as opening a pickle jar! They didnt even need to heat it up. They would have been willing to do it for free, so I was back on track for just a morning spent driving around and some beer money for the very helpful guys down at Advance Electric Motors.

So here was the problem: the key fit fine in the hub, but the keyway on the shaft does not extend all the way down.

So the hub couldnt bottom out on the little spacer ring sitting on the bearing.

So take two went much smoother. The hub slips right on once warmed to 400F. My run-out has crept up a little bit, but it was still under 0.002, so well within tolerance.

I had measured the critical distance as 21.2mm when I took the motor apart - now I am getting 22.3mm. How precise should I strive to be here? It seems like it is generally recommended to have the flywheel resurfaced anytime you have it out of the vehicle, anyway, so should I have it shaved down by about a mm to get closer to my original value? Also, is there any value in having them mill off extra weight, like the gear teeth, for example? I might also put in a new clutch disc, as the one in there is getting pretty close to needing replacement (I think).
 
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