How to replace the Magic Pie Internal Controller

[GM Canada]

Hello to the Experts (or at least those who know more then I and thats most of you! )

I have someone asking me the procedure on how to replace the internal controller. His failed and I arranged a new one. and he now has it. I was sure there was a thread here of someone doing it but I cat seem to find it. Is anyone up to describing this process from what side of the motor to open right up to completing the job and testing. It would be greatly appreciated and helpfull to anyone in the future as well.

I know there are several of the regulars here that have done major projects with the motor open and any feedback would be great!

Gary

[DirtyGinge]

aw..sheesh

Would love to, but I have no piccies of the way I did it...not much help there

I'd be happy to, in text only, unless anyone got pictures on hand which would be more beneficial to some of the non english forum members

[GM Canada]

I think Alan must have some pretty good pictures, I was hoping since you have removed an internal controller you have experience in how it was attached.

Gary

[MonkeyMagic]

Yo yo

Controller is on freewheel (chain) side. You do not need to remove the freewheel.

Check some notes on this post
http://goldenmotor.com/SMF/index.php?topic=2103.0

To remove the controller do this:

-Undo the hex bolts on the chain (freewheel) side
-With a wooden/rubber mallet or a hammer using a block of wood in between, bash the disc brake side of the motor hitting the axle with hard hits displacing as much force over the axle end without damaging the nut thread.
-Hit the disc brake side until you have enough space on the chain side to pry the wheel cover off carefully, in a crabwalk action lifting the left side, then right, then top, then bottom until you hear a loud PING which is the cover squeezing from the freewheel bearing
-With this cover removed you can access the internal controller
-Take a photo of your connections to refer to.
-Desolder all of the internal controller wires
-Remove the hex bolts holding in the aluminum heatsink, to remove the internal controller whole
-Before you install the replacement controller, apply a strip or 2 of electrical tape to the copper PCB track UNDERNEATH the phase wires (see attached pic) this will prevent your phase wires shorting to the negative (ground) track.
-Install your controller and re-solder all of the connections. Refer to your picture you took earlier to assist.
-Once all of the connections are in place, carefully reinspect and then before putting the cover on, connect a throttle to the wiring harness and connect power. Listen for beeps etc. and give it the slightest press/twist on the throttle to check if the wheel jerks. This will give you a smile on your face while you put it back together thinking of how cool you are you just fixed it lol

Should be good to go I'm sure I left 1 or 2 things out, I'm sure someone will jump in here


peace out

[GM Canada]

Nice Job Monkey, Lots of great pictures in the link too! Much Appreciated

Gary

[DirtyGinge]

dang...I wuz gonna do it now, but the Monkey beat me to it

If it helps,  I was really nervous about hitting the hell out of my pie with a hammer, tried but it just didnt budge so....

remove bolts on both covers

Using a sharp knife or 2, try to lever off the disk brake side ( don't go deep, or you damage the copper wiring)....once a small gap is made, lever off the cover in a crabbing fashion as described above

using a length of thin wood, place through the holes in the stator to the inside of the other cover ( freewheel side)

changing from side to side, hit the inside of the cover until it comes off.........

This way used a lot less force than hitting the axle , didnt put as m force through the bearings, and enabled you to work from the controller from both sides.....

See the attached pic, hammer the cover with wood, not the stator ( with the red x on it). clarified with the pic angle being wrong)

hope this helps

[GM Canada]

dang...I wuz gonna do it now, but the Monkey beat me to it

I know how you feel, many times I am working on a reply to someone and when I go to post it someone else(usually Alan, but im not complaining ) has already posted with links, photos, graphs you name it. But again, that is why I love the forum. There are many here that just really enjoy helping out. Alot of the conversations are beyond my understanding but I still like to chime in when I can with whatever photos or information I can provide and hopefully the end result is positive for the end user.

Gary

[GM Canada]

Here are a few Pictures of what appears to bethe successfull replacement of a failed internal controller. Everything appears to be working and this person is waiting for sun to do a full test drive to confirm everything is good.

Before the replacement you can see the controller is actually different.


After the replacement.




I thank you for your permission to use these photos to help others and hope to hear how well the test drive went. You can just let me know in email if you still prefer not to post in the forum. I will post the result here for you.

Gary

[Bikemad]

Looking at those photos I can see a potential problem, the metal strip that holds the controller tightly against the heat sink is dangerously close to the shunt loop (see attachment). If it's touching against the shunt, it could very easily cause the shunt to be bypassed completely, if the bicycle frame and the battery negative are not isolated.
This could quite easily be the case if a set of GM LED lights have been fitted with their fixing brackets grounded to battery negative. I don't suppose the lighting cables alone would make much difference, but if a thick lead is used to join the bike's frame and the battery negative, I think it could cause the controller to put out a lot of power , but probably only for a short time.

If the motor seems unbelievably more powerful than before, then the above could explain it.

I wonder what improvements the MX328 controller has over the MX318.

Alan

[MonkeyMagic]

hate to sound like a grumpy old man, but when inspecting the shunt I would probably resolder the phase wires if they are a bit questionable

and put the tape there!



Things just seem a little close for comfort

[GM Canada]

Thanks for that guys

This is the expertise I was looking for. I will pass on your advice.

Gary