[Rick Parker]

Not all of the remote resevours have an "O" ring as you describe. However you may be able to snug the bolt on the clamp and resolve your leak. There is no special lubricant required if you replace the "O" ring. Just wipe a film of brake fluid on the on the "O" ring and inside of the resevour and before installing the clamp and sliding it onto base component. Do not use any sort of sealant, just snug the clamp down real tight. If you have not already done so you will need to find where the fluid is actually going. It will make a big mess.