🔍 What changed
Comparing the version from 17d ago by @RCC_Community_Bot with the one from 14h ago by @tandy.
Title changed
− Cleaning your RC after a wet or muddy run
+ It ran fine after the wet session — a week later something has seized
Water plus a still-powered car is how you kill electronics and rust bearings. Do this instead:
**It came home from the wet run working fine. A week later a bearing is rough, a screw is seized, or a connector has gone green.**
**1. Kill the power.** Switch off and unplug the battery before anything else. Running a wet car to 'dry it' just spins water into the bearings and motor.
This catches people out because nothing was wrong on the night. Water does most of its damage in the days afterwards, while the car sits in a bag.
**2. Get the water out.** Compressed air (or a leaf blower) blows standing water out of the chassis, wheels and driveline.
# How to tell that is what happened
**3. Protect the electronics.** If the receiver, ESC or servo took water, open what you can, dry it fully, and let it sit before powering up. A light film of dielectric grease on connectors helps going forward — many bashers water-proof the receiver box in advance.
- **Roughness appeared without a crash.** Nothing hit anything — it just went bad sitting still.
- **It is worse at one end** than the other, usually whichever went deepest.
- **Screws feel tight starting to undo**, then free up. That is surface rust in the threads.
- **A connector looks green, dull, or brown** where it used to be bright.
- **Diff oil looks milky**, like coffee with milk in it. That is water emulsified into the oil.
**4. Save the bearings.** Bearings rust fast. Rinse grit out, dry them, and re-oil (or replace if they're already gritty/notchy). A drop of light oil on the driveline and screws keeps corrosion off metal parts.
# What to do about it now
**5. Dry storage.** Let everything finish drying before you put the car and its battery away.
Rough bearings can sometimes be cleaned and re-oiled, but **notchy — catching at the same point every turn — means the races are pitted and it is replacement only.** Rust pits do not come out.
Milky diff oil means that diff needs opening and rebuilding; it is not damping predictably any more.
# Stopping it next time
The whole thing is preventable with about ten minutes on the night. **Full procedure: [after a wet, muddy or snowy run](https://rccrashcrew.com/guides/maintenance/after-a-wet-muddy-or-snowy-run).**
The two that matter most: **rinse immediately if it was salt water**, and **never seal a wet car in a bag or box** — trapped moisture with no airflow is the worst case there is.
> **Ran somewhere dry and dusty instead?** Different failure, opposite first move — see [dusty and sandy runs](https://rccrashcrew.com/wiki/how-to-clean-your-rc-car-after-bashing).
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**Add what you know.** Ran a specific chassis through water and found out exactly what fails first on it? Found a receiver box that seals well, or one that does not? That is the sort of thing only someone who has done it can write — and this page is meant to grow.