Heng Long Challenger 2 steering problem

[sybercottage]

Hi everyone

First post, new to RCTW.

Just taken delivery of my first tank. I have just bought the Heng Long Challenger 2. Great tank, but out of the box I have a problem. Evereything works ok except for the forward steering. When you push the stick forward it starts tracking to the left. You can go straigh by putting a little right input on the stick, but not ideal. I first tried the trim control, but this has no affect at all. Thinking it might be a binding issue I did a rebind, but still no change.

The tank battery is fully charged and the transmitter has new batteries. I got my son to run it up and down to see if there where any problems with the tracks. On doing this I noticed that the front road wheel on the left side of the tank was not running straight. I removed the wheel to find it had not been stuck together properly and the wheel had set with one side flairing out. I thought this was the cause so moved the wheel to the middle of the tank, but still no change.

The tracks appear to be sitting correctly. I have not removed the top yet to look inside.

Any help would be appreciated. Dont really want the hassle of sending it back if its something I can repair myself. Retiring next year and need a new hobby. Having seen tanks at a modeln show in the summer I have the bug.

Thanks
Alan

[Jay-Em]

If nothing binds, it's the motors.

The standard motors aren't exactly the top-quality with guaranteed even running forward and backward. Since in the gearboxes one motor always runs clockwise and he other counter-clockwise, even the slightest timing difference with the brushes towards the commutator, or the winds and the commutator, can make a motor run faster forward than backwards and vice-versa. leading to steering oddities. Doesn't mean the motor is broken, but just that one motor runs "advanced" i.e. runs with a higher rpm than the other.

There's very little You can do about that, short of ordering a batch of motors and test & choose those that run absolutely the same forward and reverse. A quality and selection process they most certainly never use in Heng-Long's factories.

Taigen steel gearboxes come with tested motors, and the uneven running problem hardly ever occurs. I own about 6 or 7 steel geared Taigen gearboxes with the black motors, and they all run the same forward and reverse. So the problem with veering off course doesn't happen. Those gearboxes cost about €55.- per set. Not expensive, and the first thing to upgrade Your tank with imho.

Heng-Long's stock pot-metal gearboxes fail with alarming regularity when a little stressed.

A cheap in-between option is ordering two jamara jp400 motors @ GBP 7.- a piece. They're the most used as upgrades. But then You'll have to do some soldering, and also get the pinions from the Heng-Long motors on the jamara's. 'S a bit involved if You do not own a gear-puller for small motors.
if You never soldered, or fiddled with electric motors and stuff, nów is the moment to start, since Heng_long's "Ready to Run" actually means "ready to Upgrade"


More details about motor changes and pinions: viewtopic.php?f=79&t=20983

[sybercottage]

Hi Jay
Thanks for taking the time to reply. What you suggest does seem logical and the upgrade seems worthwhile. I have submitted a ticket to the vendor Nitrotek, but after reading some of the reviews here. I can't see a lot of help coming forward. Quite disappointed as this is my first tank and not off to a good start. However I intend to upgrade it anyway along with a repaint. I might take the top off and have a look inside to see if there is anything obvious inside. It does not have a problem binding and connects every time. I will give it a few days to see what sort of reply I get from Nitrotek before going any further.

Thanks again for the advice.
Alan

[wibblywobbly]

It might be an idea to take the top off, remove the tracks, and take the gearboxes out. Remove the motors and check the the gears spin freely with no binding. If they are the pot metal ones, get some car valve compound, smear some on each cog and run the gearboxes backwards and forwards for about 20 mins. (Put them in a bag when you do this or you will have to redecorate afterwards). This will bed the gears in. Make sure that you wash off the compound afterwards, and then re-grease them.

If it is the gears that are binding then replacing the motors won't solve the problem. Nitrotek take days to respond to a ticket, and then possibly weeks to sort the problem out. If they ask you to send the tank back you are faced with the postage costs, which will be about the same as solving the issue that you have.

It is unlikely to be an electrical problem, the white metal gears are probably the weak point on any standard HL tank, and to be honest the plastic gears are pretty good as long as they are dismantled and the slipper ring glued solid to stop the horrible ratchety noise. They also run very quietly.

The next option, as has been recommended, is to buy new black steel gears, these run silky smooth once they have bedded in.

[sybercottage]

Hi Wibblywobbly

Thanks for the advice. I think I will take the top off as I am not expecting a reply anytime soon and I have got to learn about the inside. First tank so a bit of a learning curve, though I have been modelling in one form or another since a kid. I want to upgrade and re-paint and have started looking at some options. Checking out posts on the forum for ideas and good suppliers. Really pleased with the tank apart from this one problem. Thanks for the suggestions and taking the time to respond. Much appreciated.

Thanks very much.
Alan

[tao]

This was posted under gearboxes at one point but with motors off..putting the gearshift in an electric drill and running forward and reverse with lubricant of choice for a few minutes in each direction really break them in nicely and quickly..then run them more in the tank etc.

[sybercottage]

Thanks Tao
All suggestions most welcome.

Thanks again
Alan

[sybercottage]

Hi All

Further to my previous post. I am still having problems with the steering on my Challenger 2.

I have been corresponding with the company that I bought it from and after sending a video of the problem. They determined that it was the RX18 and sent me a replacement. This has made no difference.

Problem is when the tank goes forward it veers to the left, yet when in reverse goes straight. I have checked and there is no binding with tracks or gears. Swapping the motor leads over on the RX18 transfers the problem to the opposite track. The trim control on the transmitter has no effect at all.

I can still drive the tank forward, but have to correct the forward movement with slight right hand stick movement. When doing this it cuts the speed down slightly. Moving the stick back to the middle increases the speed but then the tank starts to move to the left. I can't think of anything more to check.

Do you think the problem could be a faulty transmitter?

Any help appreciated.

Many thanks
Alan

[Jay-Em]

Late answer, but here goes: Have You tried just switching the mótors around? Theoretically, after that, the tank should run correctly forward, and slightly veer off course in reverse.

If the problem persists, it's back to square 1 : something binding when running forward, or, yet, another iffy controller.

Binding in the gearbox is easy to check : take out the motors, remove the tracks, give the sprockets a spin and see which side runs the smoothest.

[Aussie]

I'm more inclined to think the trim switch is U.S.
Try another Tx.