Troubles With the Ultra Micro J-3 Cub - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Electric Flight Discuss Electric Flight in Canada

Thread Tools Display Modes
Old 07-17-2012, 03:25 PM   #1
RCC Noob
I am: Kevin M
Join Date: Jul 2012
Location: Pense, Saskatchewan
# of RCs: 4

Feedback: 0 / 0%
Posts: 1
Total Props: 0
Troubles With the Ultra Micro J-3 Cub

       Remove this ad - become a site supporter!
Hi everyone,
I was flying my UM J-3 Cub from parkzone the other day, when suddenly the plane started gliding down even though i was holding the throttle on full. when it landed, i held the plane and turned the throttle up. the prop started spinning and then it would stop and go, and the actions of the controls were delayed. now, it may sound like i had a dead battery, but i tried out my other two, fully charged batteries with the same results. i opened up the front of the plane to take a look inside, and could see nothing visually wrong. a side note; when i held the throttle at half, the prop seemed to be pulsing and the same thing with the elevator and rudder.

does anyone know what the problem could be? any suggestiopns are greatly appreciated.

Thank You
tothemax is offline   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 07-17-2012, 03:40 PM   #2
Level 3 Supporter
★ Site Supporter ★
I am: Jason U
Join Date: Jul 2011
Location: London, Ontario
Radio of choice:
Spektrum DX8
# of RCs: 10

Feedback: 15 / 100%
Posts: 1,453
Total Props: 9
Re: Troubles With the Ultra Micro J-3 Cub

If it is not the battery then it sounds like either the motor or the speed controller is on the way out. Cheapest fix is the motor and easiest to swap out. The speed controller is integrated on the main board/brick where your elevator / rudder servo are.

The pulsing is usually what the speed controller does when a battery is below accepted voltage though, so I'd be inclined to double / triple check your batteries. Or try your batteries on someone else's plane... if possible.

Motors do wear out ... those are just little brushed motors. I went through 3 or 4 on my old UM Mustang when I had it.

Hope this helps,
MAAC# 32586 Buddy Codes: All my buddy-codes on
London Wind Mapper Weather
uberjay is offline   Quick reply to this message.
Old 07-18-2012, 08:13 AM   #3
I am: Philip A
Join Date: May 2009
Location: Cambridge, Ontario

Feedback: 21 / 100%
Posts: 1,325
Total Props: 15
Re: Troubles With the Ultra Micro J-3 Cub

2 possibilities:

1) Failed motor.

I had a UM T-28 motor fail and overheat. The plane did all sorts of weird things. Eventually the heat caused the gearbox to melt! I was using Hyperion 160mAh cells which managed to keep up with the huge amp draw. A lesser battery (ie. stock E-Flite/Parkzone) would likely just drop the voltage to the point the LVC would kick in with the resultant motor pulsing.

2) Battery/charger issue

The stock Parkzone charger really isn't the best. Make sure you are using fresh batteries in the charger to ensure you are getting a full charge. Also, if you have been storing your batteries at full charge or if they are a year or more old it's possible they are done.

My suggestion is to use a known good battery. Perhaps your LHS or a fellow UM pilot can help you here?
philipa_240sx is offline   Quick reply to this message.

j-3 , j-3 cub , parkzone , ultra micro

Quick Reply

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Name
Your first name and last initial is required if you plan on using the forum.
Which city & province you live in. This is mandatory for classified listings.
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
vBulletin Message

Thread Tools
Display Modes

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wanted: BNF Ultra-Micro J3 Cub Rotary Weasel Wanted - Airplanes 8 05-04-2012 10:54 AM
Ultra Micro J3 cub BNF - $70 Florin FS - Airplanes 6 08-26-2011 07:27 AM
Parkzone Ultra Micro J3 Cub (bnf or RTF) hs748 FS - Airplanes 2 11-05-2010 04:27 PM
Ultra-Micro J-3 Cub BNF mrrandyman FS - Airplanes 3 08-16-2010 08:06 PM
Parkzone Ultra Micro Hammertown FS - Airplanes 2 01-06-2010 06:17 PM

All times are GMT -5. The time now is 08:00 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.