Outcast Planetary Gear Stuck

Buck

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Tearing down my front diff to change oil and shim, and Inhave run in to an issue...both planetary gears are fused on the shafts.
Tried prying, needle nose pliers...they won't budge.
I'm baffled.

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Dustin Mustangs

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I would bet it is just the grease and close tolerances holding it together. Like when you loose a shoe in deep mud. The last one I took apart was like that. If that is the case, it would be very hard to pull straight off. You have to rock it back and forth while applying a steady pulling pressure.
 

Buck

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I finally got them off, after struggling for an hour.
Turns out it was not suction, but rather the pin cut out/slot on the back of the planetary gears are slightly too small for the cross pin to seat freely.
Must have been a machining error when they were fabricated.
My other two diffs - the planetary gears came right off no issue.
 

SpeedVision

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I had the same issue on my new V3 Kraton. Enough to make a grown man cry. The gear was loose but wouldn’t pop off. Only thing we can do is sand down the pins to make them fit a little better. That said, don’t want slop as that could contribute to splitting the gear.
 

Rich Duperbash

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I had the same issue on my new V3 Kraton. Enough to make a grown man cry. The gear was loose but wouldn’t pop off. Only thing we can do is sand down the pins to make them fit a little better. That said, don’t want slop as that could contribute to splitting the gear.
Not sure if you noticed, but the pin lines up with the dog bone cuts in the drive cups. These planetary gears have to be grabbed firmly on both sides, inline with how the pin sits. Once you have good hold with quality needle nose pliers, it helps to rock the gear gently off the pin. If you just yank it, it won't want to pry off. Don't sand down the pins whatever you do. They're designed to fit pretty snugly.
 

SpeedVision

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Not sure if you noticed, but the pin lines up with the dog bone cuts in the drive cups. These planetary gears have to be grabbed firmly on both sides, inline with how the pin sits. Once you have good hold with quality needle nose pliers, it helps to rock the gear gently off the pin. If you just yank it, it won't want to pry off. Don't sand down the pins whatever you do. They're designed to fit pretty snugly.

Thanks! I probably should have been more clear, I polished with 1000 grit “sandpaper”. Not sure if the new batch is different, but I’d say the pins are oversized to the point where they simply don’t fit. It still takes firm pressure to insert pin in planetary, but not “tapping it in with a punch” to test fit, firm.

Been doing planes and heli’s for the last 15 years, but used to race 1/8 scale nitro buggies (Kyosho MP-5) 1/10 scale electric (nicads- haha) and nitro on road. My first RC had a long wire that controlled the car remotely. Love the Kraton, just need to find some bigger bash spots here in the little old Midwest.

PS - thanks for all your videos and sharing your passion. Really informative, really fun, really insane, and crazy-mad driving skills… Your commentary is priceless and always good for a chuckle after a long day. :)
 

Rich Duperbash

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Thanks! I probably should have been more clear, I polished with 1000 grit “sandpaper”. Not sure if the new batch is different, but I’d say the pins are oversized to the point where they simply don’t fit. It still takes firm pressure to insert pin in planetary, but not “tapping it in with a punch” to test fit, firm.

Been doing planes and heli’s for the last 15 years, but used to race 1/8 scale nitro buggies (Kyosho MP-5) 1/10 scale electric (nicads- haha) and nitro on road. My first RC had a long wire that controlled the car remotely. Love the Kraton, just need to find some bigger bash spots here in the little old Midwest.

PS - thanks for all your videos and sharing your passion. Really informative, really fun, really insane, and crazy-mad driving skills… Your commentary is priceless and always good for a chuckle after a long day. :)
Hey thanks brother! Sounds like maybe something changed or could be a consistency issue. I can recall having to toss atleast 1or 2 pins that seemed sized wrong. On that note, it's a good idea to order a bag of spares cuz they don't come with the replacement diffs gear sets. They will bend sometimes which makes rebuilding your diff a bit sketchy. You could cut drill blanks to size with a Dremel, but I personally haven't done that. My stock pins have only failed me maybe twice out of 4 regularly used Arrmas.
 

SpeedVision

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So, in hindsight, I’m tempted to say that the tight sun gear pins could be a byproduct of not enough use. My truck is new and I only had run a couple batteries before the weather went to crap. Decided to go ahead and change the diff fluids to heavier weights. Reason I say that is the center diff fluid showed a lot more wear (darker fluid) and came apart like a dream. Wiggled the sun gears slightly and both popped out without any difficulties.

So, if my hypothesis is correct, don’t be tempted to change fluid before some good ground and pound!!!

RD - thanks for the tip on the diff pins! I have a few spare sets, but I didn’t notice that the pins were not included… That would’ve been a buzz kill if I broke one and expected to have a spare! Tempted to try the drillbit mod, but I’d rather break it the diff pin instead of the sun gear. … As always, it’s a fine balance.
 
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-Dusty-

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Im having this issue right now with my front diff. Been at it for an hour and still hasnt budged


Damn, I finally got it! Suborn lil gear
 
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olds97_lss

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I had issues pulling mine apart from my outcast as well. Mine had 4 or 5 sets of packs through it by the time I received the oil/shims to put in them.
 
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