The line does feed into the sheave at a slight angle, which certainly doesn’t help the problem. If it fed straight, it most likely wouldn’t jam, but I don’t see a good route for rectifying the situation. It was rigged this way when I got the boat, and I’m not sure what mods may have been made from the original setup by Hunter. The reef lines run from the tack down through a fair lead on either side of the boom, then down to the offending block, where they are run back up to the boom and aft through the boom to their corresponding clew rigging (I assume to blocks within the boom) from which they are run back to the forward boom sheave and down to a swivel block at the mast step, then back to the cockpit. See attached picture showing the rigging at the mast. I assume they were installed aftermarket and worked without jamming when they were first installed, though the slight angle at which the lines feed into the offending block seems the cause. I am currently soaking then in hot fresh water with a small amount of laundry detergent in hopes they will run smoother. For a longer term solution, should I mount another fairlead above the offending blocks to ensure clean entry? Or are there other blocks I might be able to replace these with? I’m not keen on putting more holes in my mast than necessary, but I do want my reef lines not to jam.