#3 MMM not dead YET, but something VERY wrong!

[JaySki]

So I installed the latest MMM, hooked it all up and was cruising it around the basement. Was running fine.. obviously.. nothing high speed.
But then.. something started acting up... at first.. then it got worse...
When you hit the throttle, forward or reverse, it just stutters... It's like it isn;t sure which direction to go? Does it in both forward and reverse. Tried disconnecting the batts and resetting... Same. Tried another set of batts.. Same. This is very similar to what the previous MMMs did before just stopping.
I am running an e-revo, 1515 1.5d, 4s TrueRc 8A, Novak BEC with red wire cut on the MMM.
Could it be the NEU? I have a medusa, but I have to solder connectors, before I can try to determine if it is the motor.

Anyone with any ideas? I plan to call CC in the AM and talk to them. If this one is half alive, I'd like to let CC look at it before it's dead.

[magman]

Could it be a loose solider joint?

[JaySki]

I checked all solder joints.. I think...
Do you mean like a loose solder joint that is wiggling?
This isn't like it is stuttering forward.. It's stuttering forward/reverse, thus no movement in either direction. Almost like the polarity is switching rapidly...
AND no more MMM TONES!

[TruckBasher]

Not to Jinx you but my modded V2 started doing this before it....(you know what)...

I hope its just a bad solder or lose connection....

let us know

[JaySki]

It's what my previous 2 did as well... But I think that failure point was much shorter because the rig was in motionat a much faster rate, maybe?

My guess is bad solder between motor and MMM. Check the bullets comming off of the motor.
Go on a high speed blast, should get pretty hot pretty quick.

[phatmonk]

Sometimes the bad connection wont wiggle.I have a 1512 1.5d and had bad cogging and the MM was real!! hot after just a few minutes.I ended up redoing all my connections and after that all was good.Now when I solder any RC I allways double check all connects.Also the MMM V2s wires are so heavy that its hard to get the solder to melt.

[JaySki]

Originally Posted by e-mikey

My guess is bad solder between motor and MMM. Check the bullets comming off of the motor.
Go on a high speed blast, should get pretty hot pretty quick.

I can't.. It won;t move.. It just jerks.. it is a rapid stutter and as much forward movement, there appears to be the same reverse movement.
It's not a forward/stop/forward/stop stutter.

[brushlessboy16]

check the connection from the wires into the male 6.5's known to cause problemss

[MTBikerTim]

I would resolder all your connections between esc and motor. It sounds like either a bad esc or solder joint but the only way to tell is to resolder everything.

Yes guys, double, triple, even quadruple check your soldering connections. It is very difficult to get those 8 AWG wires from the MMM to solder to connectors. I have a 40W iron and it takes me about 90 seconds of heat to get the solder to flow appropriately. If you do not get both pieces of metal hot enough to melt the solder you will end up with what is called a 'cold solder'. Sometimes you can tell by the fact that the joint will look hazy rather then nice and shiny. A cold solder can lead to high resistance and cause lots of problems including extra heat. I still have a v1 first batch running strong, but I have soldered many, many times.

I am sure many know this, but you heat the metal, then apply the solder to the metal, NOT the iron.

[JaySki]

Originally Posted by Larks

Yes guys, double, triple, even quadruple check your soldering connections. It is very difficult to get those 8 AWG wires from the MMM to solder to connectors. I have a 40W iron and it takes me about 90 seconds of heat to get the solder to flow appropriately. If you do not get both pieces of metal hot enough to melt the solder you will end up with what is called a 'cold solder'. Sometimes you can tell by the fact that the joint will look hazy rather then nice and shiny. A cold solder can lead to high resistance and cause lots of problems including extra heat. I still have a v1 first batch running strong, but I have soldered many, many times.

I am sure many know this, but you heat the metal, then apply the solder to the metal, NOT the iron.

Yea.. I hear what you are saying.. I have been soldering crap longer than I was ever in school and in the service.
I'll reflow everything tomorrow.

I have a mini brushless system that is doing the same thing and I have narrowed it down too a loose wire on the motor , if I press on it it will run fine till it vibrates loose .

BTW , this is going into the can , not at the connectors .....

[sleebus.jones]

Originally Posted by Larks

I have a 40W iron...

Well there's your problem! </mythbusters>

I use an 80w iron with a big honkin' chisel tip. That shows those connectors who's boss in just a few seconds.

i have a 40w 5$ harbor freight deal. thing works awesome! gets real hot! i cant believe it