[HELP] 9398 4x4 Crawler Steering

[Stingroo]

So, hi.

I'm Ray. I bought this set the other day on a whim. First Lego set I've put together in several years, but I have literally MILLIONS of pieces. I refuse to get rid of them, because someday I will give them to my first kid, or something.

Plus: they're awesome.

Anyway.

I built the 9398 and took it out. Had fun with it, rolled it, picked it up, all is well.

But now I can't get the wheels to stay straight.

The rear axle stays turned to the left, while the front axle is fine, exactly how it should be. I've tried shutting it off, adjusting by hand, and turning it back on, and it just snaps back into the wrong position.

What did I do? How do I fix this?

Thanks!

[branolego]

sounds like the gear and the rack became out of sinc. youll have to pull off the gear that moves the gear rack and line it straight again like you did when you first built it.

try this to start with.

[Stingroo]

I don't understand. Now it doesn't steer at all. This is really discouraging. :\

[dougstar]

just strip down the steering resemble it. make sure sevo is still plugged in to the battery aline necessary 8th gear and steering rack, should work after that.

sounds like fun

[Zerobricks]

You didnt pay attention when you inserted the 12 tooth gear. You iserted it when the steering rack was out of center. The easyest thing to do is just remove the pin holding the steering rack and readjust it by moving it sideways out and back in.

[dougstar]

hahaha my bad the 12th gear! lucky im not runing things!

[Stingroo]

I'll fiddle with it tomorrow after work. Thanks!

[JM1971]

Even when its lined up the 9398 tends to slew a little, its more noticable if you gear it up.

[arik]

Even when its lined up the 9398 tends to slew a little, its more noticable if you gear it up.

Btw how common is it that when reset, a servo motor doesn't perfectly align the dots vertically? Mine doesn't, so the gear rack isn't centered with a 12t gear. (But the difference is less than one tooth in the gear.) It's noticeable when driving around, not only with 9398 of course.

Hm, maybe adding one extra 12t gear somewhere might help with this...

[Blakbird]

The dots on some of the servos are not really aligned with the axle slot, so just because the dots are not centered does not necessarily mean the servo is not centered.

[JM1971]

Yeah its mostly play in the lego parts,

The dots on some of the servos are not really aligned with the axle slot, so just because the dots are not centered does not necessarily mean the servo is not centered.

Yeah, slack in the lego parts plus the differential can cause some drifting too, or at least thats how it seems, no big deal.

Edited June 24, 2014 by JM1971

[khalnayak77]

Hi guys,

I'm Raj from Malaysia.

I have a problem with my 9398 steering which I just completed this morning as my birthday gift from wife.

My crawler only steers one way...only to the right...with the turn knob on the remote rotated forward.When I release the turn knob, it(the crawler) returns to the centre just like how it should.

but when I steer to the left, it(the crawler) does not steer to left, eventhough the light on the receiver lits up.

The crawler keep going forward instead on turning left.

I'm not sure where I went wrong.

Have I missed something?

hope someone can point out what went wrong.

thanks in advance.

[OzBen]

Hi guys,

I'm Raj from Malaysia.

I have a problem with my 9398 steering which I just completed this morning as my birthday gift from wife.

My crawler only steers one way...only to the right...with the turn knob on the remote rotated forward.When I release the turn knob, it(the crawler) returns to the centre just like how it should.

but when I steer to the left, it(the crawler) does not steer to left, eventhough the light on the receiver lits up.

The crawler keep going forward instead on turning left.

I'm not sure where I went wrong.

Have I missed something?

hope someone can point out what went wrong.

thanks in advance.

Could be a dodgy servo, a few of us on this forum have had dodgy ones. If you contact lego they will send you a new one. They will need the serial number printed in the servo and may send you a paid postage satchel to send back the defective one (this happened to a guy in my LUG)

[khalnayak77]

Thanks Ozben.

that would be my last resort in the event its a faulty motor.

otherwise do you think I could have went wrong during the setting up...I.e if wrongly sncyed or missed doing something...or something?

[MajklSpajkl]

If you did what the instructions told you, then there must be something with the servo. Mine was jumping rapidly from on position to the other. I contacted TLG via customer service and received a new motor with no questions asked. I somehow managed to get the damaged one to work, but it sometimes still loses its mind and starts to get freaky :-) What I do, is that I manually force the servo left and right a couple of times and it works for a period of time, so now I kinda have 1,5 servos

;-)

Edited October 11, 2014 by MajklSpajkl

[OzBen]

Thanks Ozben.

that would be my last resort in the event its a faulty motor.

otherwise do you think I could have went wrong during the setting up...I.e if wrongly sncyed or missed doing something...or something?

There is a page in the instructions that shows the chassis and front and rear axles perfectly aligned. If the gear racks are over to one side when you built it this may be a cause of the problem.

If however you lined it all up nearly when building as per the instructions then I'm afraid you may have a servo issue.

Some close up photos may help us here :-)

[khalnayak77]

I checked the connections to the receiver from each motors and found one of them were slightly loose.

Removed and reconnected those connectors and now the steering works.....amazingly.

Wondering how come it worked for one side steering only earlier.

Nevertheless it works now.

I'm thankful for your prompt reply and support.

Thanks and cheers guys