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I'm trying to be the hero at my in-laws and help repair FIL's old toy RC tank.
The battery is intact and holding charge, as evidenced by the lights on the tank working, but nothing else works.
There was a lot of viscous yellow fluid on the undercarriage of the tank, and more inside. The battery compartment was dry so I have to assume this leaked out of the motors? Or possibly a capacitor?
Do small DC motors have an oil charge?
nope. does it have a gearbox of some sort or has Action Man pee'd himself inside?
No idea how they are built compared to cars but usually have grease/filled gearboxes and diffs but nothing electrical
Aha! It has two speeds depending on how far you depress one of the levers, that could be a gearbox I guess, although I couldn't see anything that looked like one.
So follow up question, would an internal oil slick knock out any exposed electronics? Nothing was visibly shorted...
What make/model is it?
Ours has a smoke generator thingy in it that uses a light oil.
Hmm, good thinking, but no smoke generator, just a gun moveable gun turret that fires BBs
oil wouldnt as it should be non-conductive but electrolyte out of a capacity would do nasty things as well as the capacitor not working. Not sure there would be any big enough to cause a lot of fluid though in something like that.
Has something been spilt on it?
Hmm, wondered about the capacitor, I'm not great at identifying circuit board components, but there is something that looks suspiciously like a capacitor (cylindrical, smooth outer surface) that almost looks like the top has come off and there's a sort of spongy/rubbery material poking out. But you're right, it's too small to account for the volume of fluid elsewhere.
Embarrassingly, having actually read the instructions, I realised that the headlights which I had taken as a sign that the battery was holding charge, were actually flashing to indicate low battery, I guess sticking an old Ni-Cd battery on charge for 5 hours doesn't necessarily achieve much! Will replace with a new Ni-MH for £20 and start again.
Why spend £20 if it has some charge? If it’s a total lost cause you’ve wasted £20.
What you describe does sound like a blown capacitor, they’re pennies to replace, it should have a farad rating on it. Definitely wouldn’t account for any volume of fluid though
Does the suspension contain some kind of silicone damping oil as found in RC cars?
It'd have to be a huge electrolytic cap to give the leakage you are describing. Unlikely.
No, suspension nowhere near that fancy, think biro pen springs!
No evidence of spillage on the tank, the liquid was inside leaking out.
Actually with a bit more investigation, it looks that the BB firing mechanism in the turret is an 'airsoft' type gun. Wikipedia says that automatic firing, spring loaded airsoft guns feature an electric motor gearbox, so maybe that's the source. It's certainly pretty oily looking...
Will experiment with charging the battery more before replacing, but hopefully if the oil spill hasn't damaged anything we might come out of it with nothing more than a malfunctioning BB gun, probably for the best with a 7 year old and 9 year old anxiously wanting to get their hands on it...
Sounds great..... we need pics 🙂
I'd clean the goo off it, identify and replace whatever looks like it's blown, then take it from there!
Edit: a quick google shows that the gun gearbox doesn't look like it has anything more than a little light grease in it.
Any chance the tank was driven through some crap? How big is it?
Pictures please!
Lots of them showing the outside and the gibbons inside 8)
I’m an Engineer so it’s only ‘cause I’m a nosey Engineer 😆
Sorry guys, it's nowhere near as exciting as you might think, actually surprisingly plasticcy and the internal gubbins are surprisingly sparse!
Won't be back at FIL's till later in the month, will grab some snaps then.
Edit: This looks similar but FIL's doesn't have the speaker or smoke generator. Also doesn't show the mechanism in the turret
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