That’s had extended periods between oil changes causing build up of sludge.

 

What's the best way to sort it? I'll be booking in a service

 

Take no notice of the bmw cbs do oil/filter every 6to10k or 12 months.
That will save the engine and it will stay cleaner.

 

Yeah I planned to do it every 12 months as I won't do much mileage in this car. Although I might do it every 6 initially to maybe try and help clear some of this up

 

Ahhh it’s not that bad. Get a new cap as that one looks like it could be sealing better. Do a few short changes with cheapish oil something like mannol 5w30 (run the car for 1-3 months then do a change) to loosen some of the sludge and varnish. Then drop the oil and add a better quality oil.

- the crap under around the cap is just dirt stuck to the oil because the caps had a bad seal (same as what you get on the outside of pipes with a boost leak etc).

- the varnish under the cap (the smooth brown colouring), is no concern whatsoever, could it be cleaner? Yes. Will it harm anything? Absolutely not.
Hope that helps

 

I do the above with every new to me car.
That way it gets a clean and then i know when the oil was last changed and what oil is in it.

 

Thanks guys I will get a new cap and get on with the oil changes