Nothin's Easy

Saturday I set off to buy some nuts and bolts for the motor mount. I needed:

• Seven 17 mm nuts and lock washers for the adapter plate


• Two 1.5" 13mm bolts and stop nuts for the ring clamp


• Two 5" 14mm bolts to connect the motor mount to the subframe


• Plus I needed 3/8" hex drive and some locktight for the flywheel.

Seemed pretty easy. 2 days, 8 trips and 5 hardware stores later I still didn't have what I wanted, but I think I have enough to put it together.

First problem is finding metric anything. Sure you can find metric nuts and bolts, but the selection is pretty limited and aren't hard enough for my application - grade 5 is OK, but grade 8 is better. And 17 mm nuts could be found, but not at the right "pitch" - how close together the threads are. You can find 1.25 and 1.75 at Home Depot and Lowes, but I needed 1.50 which I finally found at an ACE Hardware.

So I went for SAE for the ring clamp bolts and the motor mount bolts. I couldn't find 5" grade 8 or grade 5 in 7/8 width, so made the dubious choice to buy 6" lengths, cut threads with a die and then cut them down to size. Comes out grade 8 is hard to cut (duh) and I didn't have a 7/8 die. Disgusted, I took a break to rethink the mounts. I was concerned that the lower rubber piece would extend down too far - cutting the ground clearance. Since my bolt idea isn't working and an electric motor doesn't create the vibrations that an ICE does, I decided to keep just the upper rubber piece and run the bolt directly through the subframe. This way, a 4" bolt will work which is what was shipped with the mounts.

So the ring clamp bolted up to the motor well after "adjusting" one of the bolt holes a bit to improve the alignment. The "torque bolt" idea was scratched as the bolt heads that stick through the holes I cut in the ring clamp and should keep the motor from spinning in the clamp.

The instructions for the adapter said to use a 3/8" hex drive to tighten the allen head bolts to 35 ft/lbs. I found a 3/8" hex drive at Kragen, but of course it didn't fit. I used an 8mm hex key to tighten the bolts by hand and so I traded in the 3/8" unit for an 8mm one - but it didn't fit either =\. I ground down the 8mm a bit and NOW it works.

The adapter is now on nice and tight and next is to make sure the flywheel is properly set to the "magic distance" - this is how far the flywheel is from the adapter plate so that the clutch operates correctly. The instructions say the flywheel needs to be 1.520" +/- .01" from the adapter. There is a hub that mounts on the motor shaft which the flywheel bolts to. This hub can be adjusted back and forth until the distance is correct. But the only way is to do this is to mount the flywheel, measure the distance, take the flywheel off and adjust the hub. With a 16 pound flywheel and the motor on a cart on the garage floor, this is a real pain in the back! Took me 5 tries, but it's now within tolerance.

So, we got the ring clamp on, the adapter on tight and the flywheel and clutch finally in place. I still have to drill the holes in the subframe for the motor mounts, but once that's done I can drop the motor in for real : )