Sunday, November 9, 2008

Installing the motor

After taking a nice vacation to Oregon for some quad riding in the dunes and getting over a nasty cold I was finally able to get back to the project. First I needed to hoist the motor and transmission down into the car so I could start measuring things and figuring out how to build the motor mount. I knew this would be a two man job even with the hoist so I grabbed my neighbor again for some help. The top center bolt of the adapter plate to transmission turned out to be perfectly balanced for the setup.

Here is another closer shot to show what we have to work with. You can see the original two motor mounts that we need to eventually tie into. Still plenty of room in here for other things later such as batteries.

Here is a top down view just to show another angle. My neighbor had a good idea of using this strap to support the motor weight so the car could easily be moved around if needed.

A quick note about the rotation of the motor. It turns out that all Honda engines do not rotate counter clockwise like I read. At least the S2000 rotates clockwise. This effects where the front motor mount holes need to be so make sure your motor is setup correctly before making your motor mount.

Let the work begin. Here I am making my first cut of the project.

Here is one of the brackets made to set against the adapter plate and utilize those bolts to build a frame around the motor. A plasma cutter makes these custom corners a breeze. The metal used here was 3/16" x 3" flat bar.

That same mount shown in place.
Next I welded 1/4" x 1 1/2" angle to the plate.
I made another plate for the other side of the motor. These couldn't set at the same level on this side and are slightly higher overall because the closest bolt to the center is below the angle iron in this shot and can't be seen.
Here is the finished support frame. The front bracket was also 3/16" x 3" flat. The center was notched out for the secondary output shaft of the motor. The two ears were added to bolt to the front of the motor. We'll see how all this fits a bit later.
Finally on the frame assembly two holes have been drilled on each side to mount the brackets that attach to the old motor mounts. These must be bolted on and NOT welded because the motor mount bolts are at an angle and the motor will not drop in properly if it's all welded together.
Here is one of the two motor mount adapters. It's hard to see here but there is a bend to metal to transmission from the angle of the motor mounts to the level frame support. The larger center hole on the left is a 1/2" hole and existing motor mount bolt goes here. The slightly offset hole from there is an alignment hole where the motor mount has a tab sticking up. The two smaller holes are for the mounting to the frame support. I used 3/8" bolts here and drilled the holes one size up from there. The most important feature of these adapters is the small strips of metal on each side. They create a triangular shape and add a great amount of support against the weight that will be pushing down on them.
Here is a quick shot of the whole assembly before we take it out for paint. It's much easier to the angle of the mount adapters in this shot. At this point I've probably installed and removed pieces of this a dozen times as the measurements were made and it was all built.

Here is the whole assembly again after a primer, two coats of semi flat black and one coat of clear.

Here is a shot from the back side of the assembly.

Here are those two ears I was talking about earlier. These are the only two spots on the motor. Depending on how you build your plate and fasten it to the motor these two bolts could end up anywhere. You do have the option of rotating them in 90 degree increments though by rotating the motor on the adapter plate. I didn't feel like taking everything back apart and didn't see much benefit from a rotation so I worked with what I had.
Here we have the completed and installed motor mount from the right side of the car. The largest bolt on the plate connecting to the adapter plate originally called for 47 foot pounds and that was reused here. The motor mount nuts were torqued to original spec of 40 lb/ft and the newly added 3/8" bolts were torqued to 35 lb/ft.

Here is a shot from the right side of the car. You can see here that bolt is just below the angle iron and a tight fit. Make sure you give yourself enough clearance to get a socket in there. Also I mentioned earlier this side had to set slightly higher. You can't really see it here but I crafted two 1/4" x 1" x 3" spacers to set between the frame and the mount adapters to make up the 1/2" difference.
Here is a shot of the entire assembly installed.
With this done I finished installing a few last things on the transmission (shifter, console, etc). Next I jacked up the rear of the car and put the transmission into 1st gear. I then tried the old 12 volt test again and the back wheels started spinning forward. Make sure to keep an ear out for any strange noises or vibrations. Things should be fairly quiet or something is wrong.
So then I couldn't resist. I lowered the rear of the car and ran the motor again. I was amazed at the torque from only 12v. The car immediately lunged forward and begin moving fairly quickly. I'm pretty excited at this point as things are slowly falling into place.


albert said...

I'm impressed. Any thoughts on making a conversion kit for others to convert their s2000 to a highway electric?

Brian said...

It's possible if there was enough interest. The biggest problem in offering a full kit is available options when doing a conversion. Some people may want a large motor, others a smaller for cost reasons. Some may prefer lead acid batteries for a shorter range and again cheaper vs going with lithium.

All of these change the parts you'd provide in the kit not making it cost effective to produce them. So I'd probably just have to pick a middle of the road build (basically what I'm building now) and your stuck with those options if you want the kit.

David said...

Fantastic work. I love the simplicity of the motor mount design. Keep it up!

Charles Le Pere said...

I noticed that you left the rubber shock absorbers from the original motor mounts in your new motor assembly. I've noticed that other EVers have been making sure to remove those rubber shocks when installing the DC motor. As I understand it, the shocks are there to absorb the vibration of the idling ICE motor. And as you know DC motors don't idle an therefore no need for the shocks. I'm mentioning it b/c it seems that the low end torque of your massive series-wound could damage your transmission/adapter plate/etc. over time if there is room for your motor to torque around when accelerating. Here's a link to another site that kind of talks about this, this guys rubber mounts were immediately shredded upon powering up his motor:

By the way, incredible site! I'll be following your progress all the way to the end! (Nice choice on batteries, too - what's your estimated mileage with the LiFePo4 pack?)

Brian said...

I'll have to look into the mounts. I've heard very little from people but the recommendations I've heard is try and reuse the original motor mounts so that you do have some give with the torque of the motor otherwise you can end up break or bending your mounts without that give.

I do see your point though on the mounts being able to give out as well. I'll check out that build you mentioned but I'm hoping since I'm not installing anything too crazy here I'll still be ok.

Brian said...

Well crap he is using the exact same controller and motor as me so I better do some more research on the subject. Thanks for the heads up!