Trailer master cylinder does not maintain fluid level

[Cigars n scotch]

I have a question that I know nothing about.

I will disclose that in April I bled my brake lines with the help of my dad and refilled. I had to change out a leaky seal which meant repacking all bearings and such.

For some reason my master cylinder on the trailer tongue is sucking brake fluid, it seems like I have to refill it every time I go out. This worries me because I am driving a 3 hr trip this weekend to camp at J. Strom Thurmond Lake.

There are no leaks, why would the brake fluid keep emptying?

[kaneboats]

Because there is a leak.

[bergermaister]

Second that. I just redid all mine and a new actuator as well. Fluid shouldn't go down at all really unless your pads are wearing and the calipers have to compress further to compensate. But that is more slowly over time. You're definitely losing fluid somewhere.

[wolfeman131]

Because there is a leak.

I only posted the above since you beat me to that reply!

[kaneboats]

That's OK. We're used to you being a little slow. That's why they sent that special short bus for you every day.

[wolfeman131]

meh, this is the only short bus I ride:

http://www.shortbusskims.com/skimboards/

[kaneboats]

That's a cool name for a board. Very memorable.

[Cigars n scotch]

Leak you say? Hmm, I see no leaks but I will just have to look harder I guess.

Leak in the lines?
Leak in the nipple? (Well maybe for a breast feeding mother)
Leak in Seal?
Leak where else am I forgetting?

[bergermaister]

1- under the tongue - where the line goes into the actuator/master cylinder. If it's dripping from there you many never see it if it's when you're going down the road.

2- all T-splits where the lines go off to other wheels

3- each of the calipers where the line goes into it

4- bleeder vales - are they tight?

5- caliper itself leaking may be tricky to detect...

Break fluid is usually really good at removing paint so look for any thin spots or rust. There are some vids on youtube about how to manually bleed your breaks by using a screwdriver to pump up the actuator's master cylinder.

That may also work to look for any leaks when under pressure. Search for "Asian Bass Guy Break Bleeding". He does a decent job of showing and explaining the parts and steps although they can be lengthy.

Basically pump it up into a pressurized state (brakes on) and go around looking for wet spots.

[Cigars n scotch]

Ok so here is where I am at after looking some more at the the lines and all. I can see no visible sign of a leak on the t splits, each caliper, bleeder valves are tight, seals are good. Haven't checked the caliper itself by removing the wheels but I gave a good look all around and didn't see any fluid.

I did notice though that after removing the reservoir cap that the fluid had gone down a little it since filling it last night, so it leads me to believe that there's a leak on the master cylinder but I know under the tongue where the line goes into the actuator it is not leaking as far as I can tell. There is "wetness" underneath there but I am not sure if it's from fluid that I spilled while filling as I did spill a little bit. I wiped everything down to dry it off as much I could so I will check it tomorrow again. I did notice that underneath the tongue right in the open spot where the solenoid is there's a little paint that is peeling away, again not sure if this is spilled fluid or leaking.

I have a hunch "maybe" the master cylnder is leaking but not positive. I'll keep an eye on it and report back tomorrow if I notice the fluid level down again. (the trailer hasn't moved)

Thanks berg for the pointers.