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6 days with a leaky brake
First post...yay me 
Being relatively new to MTB, and the world of hyrdaulic disc brakes in particular, I need a word of advice.
Riding to work southwards down the Spit during the week my front brake decided it would be of no apparent use. The back works fine. I tested it once I rolled over the bridge, finding that it did very little to stop me, and barely even slowed me down. They're Tektro Auriga Comp hydros on a Mongoose Amasa Comp.
I checked the disc once I made it to work to find a nice film of dark oil in the inside face. The lever has a bit of play in it, but it has been that way for a while. There were no splits in the hose anywhere. I'm guessing that its somehow leaked, and has contaminated the pad.
Questions:
Would that automatically mean that the source of the oil is the caliper? Can they leak through the pads? Is a flush going to show me whether the caliper is stuffed? Are these things prone to leaking now and then, is it 'just one of those things'? While it hadnt been used for a few weeks, it wasnt like it had been sitting for months without activation.
Can the disc still be used by cleaning it? I'm assuming the pads will have been soaked and are now useless, and will need replacing anyway. I intend taking it to the LBS to get looked at, but it'd be nice to stew it over before that happens. Unfortunately the bike is not worthy of a complete brake upgrade. And I cant afford since I bought another roadie...
Cheers
Jim
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The oil may also have run out of your fork and down to the disc, but you'd probably have spotted that right away, eh?
Hi Jim,
I'm guessing a broken/scratched O-ring in the caliper or you've had a piston come out too far and get stuck, but you'd have noticed the brakes rubbing I think if that were the case? Hmm, maybe not if the pads are close to wearing out. Unlikely to be forks I think unless you have a terminal structural problem with the lowers.
Yes, pads are probably stuffed. You could clean them with brake cleaner (I've done it) but they'll be a down on power and very noisy. I have a spare set of new discobake pads to suit the Aurigas that aren't bad that my son won't need if you don't feel like paying LBS prices.
Your disc will be fine if cleaned thoroughly with disc brake cleaner - can be bought from car or motorbike accessory shops.
Hope this helps.
Fork seals are ok, no weeping around the legs. Better take a look around the lowers. Pads are 75%, due to first owner riding it about twice in two years. Stating that, the seals are probably sorta hard from lack of lubrication through usage. I'll get them serviced, clean the disc and see how I go.
I'll let you know about the pads hawkeye, thanks for the offer.
Cheers
Jim
Your comment about the o-rings being kinda hard prompted another thought: Something else to check is whether your system has inadvertenly had DOT brake fluid put in it rather than the mineral oil Tektro's use.
If this mistake has been made, you ought to get the *all* seals replaced in the brakes - mineral oil brake systems and DOT bake fluid don't mix, and vice-versa. Your LBS should be able to tell what fluid type is in there now. I assume you've not bled your brakes yourself yet.
Good point. AFAIK the fluid is original. Scary thought. Its going in soon for a check either way, thanks fo the input lads/ladettes.
Jim