My honda accord 2002 V6 coupe has a brake oil leak (rear) and it seems like brake oil is leaking from the dust boot so I went ahead and replace the seal and dust boot. I pressed the brake after the replacement but brake oil is still leaking only when I press the brake. The piston looks fine and no rust so I didn't replace that. I am lost and I have no idea what I should do to fix this leak, can someone provide some thoughts on this?

If I am not mistaken, brake oil shouldn't go pass the brake caliper seal. If it is still leaking, does that mean the new seal is bad?

 

I think that you are supposed to hone the cylinder to remove any glaze that has built up over time. *Back yard mechanic may just hand sand it, but a hone would ensure that you don't get it out of round. (Same as an engine cylinder).

I assume it an actual O ring designed to fit and not just an off the shelf from a hardware store?

They are under extreme pressure, so it doesn't take much for the brake fluid under that pressure to be able to blow by an O ring with a poor sealing surface area.

 

It is true that I didn't sand the piston because when I touch the surface, I didn't feel any bumps or rough surfaces. This caliper was replaced 3 years ago and I believe it was a refurbished one, didn't think it will give me problems now.

I bought the repair kit from Rock Auto and the brand of the repair kit is Doorman, I hope this is a good brand. Does the seal need to be set in or will it seal itself after a while (dumb question I guess)? If this leak is not stopping, should I replace the caliper or the piston or anything I can do?

 

I would personally just replace the caliper at this point. It may have been close to being out of spec after the first rebuild and hone.

I am the type of guy who would have tried to rebuilt it my self as well, especially if the replacement is pricey. I have rebuilt the master cyl on my 93 with a -$15 kit rather than pay the $43 for a remanned one. Sometimes it just doesn't work out.
It comes down to how much effort is it worth vs the cost to replace.

Dorman is usually okay quality, though aftermarket is never as good as OEM Honda.

*It is not the piston that needs sanded/honed, it is the inside of the housing that would need it. All that it takes is a section, usually at the bottom that looks stained etc that would keep the ring from sealing under those kinds of pressure.

 

Thanks for the reply, I'll get an OEM caliper if the leak continues. I'll have to monitor it for a little while. It is an old car and a little maintenance cost is unavoidable.