Please can I have some advice. I've sanded off a bit of rust, put kurust on it, it turned black but unfortunately I didn't put a primer on it 😳 and then it rained 🤦‍♀️

Yes I'm a bad car owner. 

 

Hopefully it'll stay dry today, should I do a bit more sanding, then reapply kurust then primer or just put primer on it straight away? 

 

Thanks 

In my experience it should be fine as long as it reacted and dried.

Years ago I did exactly as you on a very old car and never got around to putting any paint on it in any way. I didn't see any rust whilst I still had the car.

 

If you want to be sure lightly abrade the surface, then reapply and then prime as per the manufacturers instruction.

I used Kurust on my metal gates where the paint had flaked off, never topped it with anything and rust hasn't come back two years on, so I wouldn't worry!

Will kurust help on this? 🥴

You could use it, but might be better loking at bilt hamber.

Regardless of what you use to kill it, you'll want a high zinc primer to reduce the change of future rust, then a suitable top coat to protect against stone damage.