dtwolfen

I was bleeding my brakes yesterday and curiosity got and took the reservoir cap off, Now it leaks, I get 5 good brakes in before the lever reaches bar. Pull back hood and oil is seen at the cap. How can I fix this? I have tried taking off and resealing but do I need a new seal? Maybe a grease or something will keep the oil in? Would like some help please,
Thanks

Metaluna

Sounds like there's a bad seal somewhere, possibly the seal between the main piston (or whatever you call it) and the master cylinder, which is supposed to close off the system once the piston travels far enough, and prevent the reservoir from taking the full hydraulic pressure seen by the brake caliper. Either that or you overfilled the system initially, maxing out the expansion bladder and causing an over-pressure situation in the reservoir and damaging the gasket.