Rust/Water proofing motor internals

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Rust/Water proofing motor internals

Post by Rifle » Oct 23, 2012 7:11 pm

Trying to figure out the best way to deal with the fact that water can potentially get into hubs and rust things up as well known now through justin's video. I'm wondering why in the video they don't suggest a varnish applied to the internals (such as is done here: ... it=varnish) as well as vent holes for drying? I want to open mine up and see if any of my rainy riding has gotten into it (I feel like it hasn't since the connections have silicon tape and drip loops and I don't store it out side in the rain) but since that will then break water-proofing seals I feel like I should do the vent holes / varnish after doing so.
2807 9c front hub. 48v 20ah Ping. 12s2p Lipo.

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Re: Rust/Water proofing motor internals

Post by Kingfish » Oct 24, 2012 10:49 am

Also RUST: DIY Hub Motor Repair & Restoration.

It would cost less than a $1 USD to varnish a motor correctly in production. And drilling two small holes into the periphery - one on each side of the hub covers for weeping seems like a no-brainer. I haven't a clue why they don't do this other than just to cut corners. It drives me batty. It took so much work to repair mine - I wouldn't ever try it again EXCEPT that there are no viable alternatives for where I live - which is in an urban rain forest.

Perhaps one day someone could come up with a method where you drill two holes, inject a lightweight medium that acts as a conformal coat, go for a quick ride to ensure that the stuff has entered every crack and cavity, then drain it out and let'r dry. Done. The enterprising guy that can come up with that process... perhaps a service that provides a Dr. R&R FeelGood experience for say $50 (bearing & wire upgrades extra), could make a tidy sum in the wet counties. Just order a new motor and route it through the Upgrade factor before sending it to me please. I'll take two. 8)

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Re: Rust/Water proofing motor internals

Post by mat h physics » Oct 24, 2012 11:25 am

Have you considered tooling blue (aka gun blue) for the steel laminates? Aluminum will produce an oxidized layer naturally, but may benefit from a sacrificial anode.
IMO, varnish has an inherent "thickness" which will crack under thermal cycles. Many water repellants, including PTFE, are avb, but applying some can be quit a task.
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Re: Rust/Water proofing motor internals

Post by itchynackers » Oct 24, 2012 2:21 pm

I just tore down my Pikes Peak motor (which was coated with high-temp vht enamel). Nothing wrong with it, just "improving" it for next season. Anyway, the only change I saw was that the enamel came off the magnets. Everything else looked pristine the way I left it. I suspect it was my prep job. I wasn't sure I could roughen the magnet surface to paint, so I just cleaned and left it. However, there isn't any visible rust/corrosion/damage of anykind (I was running ATF fluid).
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Re: Rust/Water proofing motor internals

Post by LI-ghtcycle » Oct 24, 2012 4:24 pm

Anything that is going to last has to be a form of a controlled oxidant such as bluing agents used with firearms, or parkerizing (sadly parkerization only works on ferrous metals, perhaps anodizing will work for the aluminum parts?) but sure, some nice varnish would be better than not, I bet there is a form of marine coating/treatment that would be ideal. :idea:
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