Brake fluid leak when bleeding brakes

[dominator]

I have an older Boatmate trailer (~2001) with Atwood actuator, and I had mechanic bleed my brakes last year. This year I decided to get a device that measures water in brake fluid, to my amazement it showed >4%, so I decided to bleed the brakes again and do it myself. I have Motive power bleeder that I use on my vehicles and I got an adaptor for the actuator. I usually pump the bleeder to 15 PSI or so, but with trailer I decided to go to just 10 PSI. When I got to that pressure the brake fluid started dripping from under the actuator. I checked the master cylinder hose fitting and it's not leaking from there. I am sure brake fluid doesn't leak otherwise, because I check fluid level regularly and it's always good. Couple of questions:

* Did I blow a gasket on the master cylinder, if so should I replace the gasket?
* Can this leak be the reason why my brake fluid went bad in just one year or it's normal for brake fluid to go so bad in 1 year?

[bturner]

You should be able to go easily to 20 PSI without leaking. The first place I would check would be the seal from the Motive Bleeder to the fill hole in the MC to ensure fluid isn't getting past and you're just not seeing it. This has happened to me before and reseating it and using a bit more pressure fixed the issue for me. After that it would be the seal between the MC and the body of the actuator. If this is rotted or damaged certainly that could be a place for water to enter however brake fluid is known for it's water absorption properties which is why it's recommend to replace it frequently.

As far as did you cause this.... If it's leaking with 10 PSI something was wrong to start.

[dominator]

I think it’s a gasket between the MC and actuator. I did check the bleeder and it wasn’t leaking.