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TannerT
2009.06.24, 03:11 PM
I just finished installing delrin servo gears on MR02, I followed the exploded view pdf and reassembled it. I turn on my tx, then the car, and it turns all the way to the right, you can't turn the wheels with the tx, steering trim or anything. There is a buzzing noise coming from the servo while it's on. I didn't take the servo motor wires off, I left everything on. I just turned the car on and it centers normally, but when I turn the tx on, that's when it gets wierd. I double checked my work multiple times and there's nothing wrong from what I can tell. It's really starting to bug me. Help is appreciated.

herman
2009.06.24, 10:50 PM
hmm... did you put in the vewwwy vewwwy small washer back in between the servo gear? :D

TannerT
2009.06.25, 08:49 AM
It never came with one when I bought it. It always worked before, but the steering trim had to be all the way to the left for it to run straight.

I fixed the full lock thing but this is what it does now:
http://img190.imageshack.us/i/0625090938.mp4/

I'm only using the steering trim, not the wheel on the tx.

herman
2009.06.26, 04:49 AM
hmm... you could try another tx with your car first to see if somehing is wrong with your tx... or try your tx on another car...

there's supposed to be a vewwy vewwy small washer :D in between the servo gears... take a look at the manual... you could probably order it (part no mz8-3 servo gear shaft set it comes with three vewwy vewwy small washers the two are extras :D) , or fabricate it from a refill plastic ballpen ink tube cut a small portion at the end of the tube to approximate the vewwy vewwy small washer...

download the manual from the link below to see exactly where the washer opps make that vewwy vewwy small washer goes...

http://mini-zracer.com/forums/showthread.php?t=32033&highlight=manuals

good luck i hope this helps... :D

TannerT
2009.06.26, 09:56 AM
I tryed my MR01 tx on it and it did the same thing. Would the washer make that much of a difference? I think I'll just order one.

ianc
2009.06.26, 10:51 AM
I'm not sure that washer is going to help you...

Let me get the problem straight:

It looks like from your video that the steering seems to work (kinda), but that even with the trim adjusted all the way to the right, the wheels still want to be pointing left?

Is this car AM? If so, there is a little pot on the board itself that you can use to adjust the center position of the servo. It's on the top of the board. Turn on the car and use a jeweller's screwdriver to adjust it until the wheels are pointing straight with the trim centered.

HTH,

ianc

TannerT
2009.06.26, 12:04 PM
I can steer the car full left or full right using just the steering trim. If I try and adjust the steering trim using very small increments, it slowly turns the direction I adjusted it. If I use the wheel on the tx and turn it right, it slowly returns left and then stays there. I don't think it's AM. I tried adjust the pot on top of the board and it didn't do anything.

ianc
2009.06.26, 12:18 PM
If I use the wheel on the tx and turn it right, it slowly returns left and then stays there.

You mean it returns all the way to the left (lock)?

How about if you use the Tx wheel to turn to the left?

How did you fix the original full lock problem? Are any wires getting pinched in the chassis or cover plate?

ianc

TannerT
2009.06.26, 12:23 PM
You mean it returns all the way to the left (lock)?

How about if you use the Tx wheel to turn to the left?

How did you fix the original full lock problem? Are any getting pinched in the chassis or cover plate?

ianc

Yes.

The servo just buzzes becuase it's already in that postion.

Someone on a different forum said to take a pliars and hold the metal part on the servo pot and turn it untill the servo stopped making noise.

There is no pinching, it does this even with the cover plate off.

ianc
2009.06.26, 12:54 PM
I ask again, how did you fix the original full-lock problem?

Under the top cover is not the only place the servo wires can be pinched. IIRC, the wires (3 servo and 2 motor) are routed to the side of the servo mechanism and there is the possibility of pinching there.

Looking at this logically, if the car was working properly before but isn't now, then you must have done something to it in replacing the gears. That something could include pinched wires, breaking strands in wires, stressed solder joints, etc.

Look carefully at the routing of the wires. Remove the servo plates and mechanism from the chassis and test again. Examine all connections to the pot and servo motor and make sure all are good, solid, and contain adequate strands of wire. Sometimes with bending or moving the wires, you can snap off a few strands of wire at the soldered connection point, and while the wire is still connected, it may only be hanging by a thread.

The fact that the car behaves the same way with two different Tx's indicates that the problem is with the car, and since that's what you were working on, it's highly likely that something was disturbed during the repair that's causing the condition,

ianc

TannerT
2009.06.26, 03:14 PM
I ask again, how did you fix the original full-lock problem?

I adjusted the pot using a pair of pliers.

I resoldered everything around the servo and pot about twice. I turn the tx on then the car, and it turns full lock left I can't adjust it with anything. Or I adjust the little pot on top of the board, turn on the tx then car and it doesn't center, you can steer it with the steering trim like above. It centers perfectly if I just turn the car on, and not the tx.

If I try and adjust the car with the steering trim it's opposite. If I trim it right it turns all the way left, if I trim it left it turns all the way right

ianc
2009.06.26, 04:10 PM
I adjusted the pot using a pair of pliers.

Are you talking about the main servo pot (not the one on the board)?

I can't see how you would 'adjust' that with pliers... It is keyed to fit on the the servo gear one way and held in the servo housing by means of small circular clips so it can't rotate in relation to the housing.

How did you 'adjust' it?

ianc

TannerT
2009.06.26, 04:45 PM
Yes, the main servo pot.

I gently turned it untill the servo stopped spining.

ianc
2009.06.26, 05:08 PM
I gently turned it untill the servo stopped spining

And given my earlier statements about the importance of the pot being properly located with respect to the servo gears and housing, does this seem like a good idea to you? Is the pot now moving in relation to the housing due to your 'adjustment'?

ianc

TannerT
2009.06.26, 05:19 PM
Here is the quote from a different forum:
this happened to me too a while back. turn the car on and have the servo assembly out of the car.
take the pot and take a pair of pliers and hold the metal knob. Adjust it left to right until there is no buzzing and servo motor rotation. that will help you a lot. place the pot in the assembly, then drop everything in.

It sounds like you are turning the car on first.... always turn the transmitter on first then the car.

And given my earlier statements about the importance of the pot being properly located with respect to the servo gears and housing, does this seem like a good idea to you? Is the pot now moving in relation to the housing due to your 'adjustment'?

ianc

It did the same thing before I even touched the pot, but my 'adjustment' probably made it worse. The pot doesn't move when I turn the car manually, how would I check if it does? If I purchased a new pot would that fix the problem?

davskee
2009.06.29, 10:33 PM
You are missing the tiny washer that pushes the gear closer to the potentiometer. If the potentiometer isnt seated correctly the servo motor will keep trying to spin and forcing your steering towards the direction the servo motor is spinning. If you keep the car and controller on during this it can cause your servo motor to burn out. So until you buy a servo pin set from Atomic or Kyosho i would stop messing with it.

herman
2009.06.30, 05:25 AM
check out the exploded diagram on the link below...
http://kyosho.com/jpn/support/instructionmanual/mini-z/pdf/miniz_02_t.pdf

part no is mz8-3 servo gear shaft set... it comes with 3 vewwwy vewwy small washers... the two are extra...

kyosho didn't put the washer, i mean vewwy vewwy small washer in there for nothing... :D

hope this helps... let us know if it does... :D

herman
2009.07.16, 01:40 AM
hey boost what happened to your car? hope you got it fixed...

WhiteSatin
2009.07.16, 03:20 AM
I'm having the exact same problem with a brand new board, brand new gears, brand new everything basically, and I have the washer. The wires definitely aren't pinched, they're exactly where factory puts them, and I haven't soldered a thing. How about that? lol. I've dis and reassembled it 4 times now. One time, it worked, until I put the cover on, another time it worked until I put the wires in place, before i put the cover on. I'm 90% sure I have a broken connection somewhere that is making connection sometimes, depending on where the wires are. Maybe if 1 of the potentiometer wires isn't connected, it will behave like boost's?

Man, why the **** couldn't they just put a normal servo in this thing?!?!?!

herman
2009.07.16, 04:27 AM
hmm... that's odd did you get it brand new or second hand? if you got it new you might want to bring it back to the shop where you got it... some shops will even replace it...

i'm thinking it will be more difficult though if you got it second hand... if there's a shop neareby you might want to have it checked out... what other stuff is brand new? i'm thinking the pot, the servo motor, or the wires if you haven't looked into them already...

hope this helps...

WhiteSatin
2009.07.16, 06:05 AM
I bought it new from an online retailer. I contacted them letting them know of the issue but haven't heard back.

TannerT
2009.07.16, 11:53 AM
I fixed the problem. My servo wires where backwards and the negative fet leg for the servo was soldered together. Since your board is new I'm not sure that this is the problem but, check on the bottom of the board where the negative and positive servo wires solder to the 2 fets, make sure there is a space on the 1st and 2nd fet leg of the positive wire and a space on the 4th and 5th fet leg of the negative wire. Here is a pic of how it should look:http://i810.photobucket.com/albums/zz26/MinizRacer/MR02_Board.jpg
Make sure the pot wires are soldered securely, check for broken wires, and check if your servo motor isn't wired backwards. Also check the fets, It's possible the steering fet could have fried.

herman
2009.07.16, 09:37 PM
hmm... boost, so it wasn't the vewwy vewwy small washer after all? :D

whitesatin... any news from the online retailer?

WhiteSatin
2009.07.16, 09:49 PM
Actualy I have an ASF board, so our problems aren't the same it appears. My board definitely doesn't have the problem yours did.

They wrote back and told me to send it back to Kyosho. So, good, I'm without my car for a couple/few weeks undoubtedly, then Kyosho will give me some bs saying my warranty isn't valid (probably because I cut the battery wires shorter), and then I'll be out 80 dollars.