How to repack a traditional stuffing-box type stern gland
If your traditional stuffing-box-type stern gland was dripping too much last year and there’s no travel left in the gland nut, it’s probably time to repack it. Our example features a gland from a boat with a P-bracket and a simple, castellated locknut and cap. Types vary: some have a nut and a separate ‘pusher’, which compresses the packing and will need to be slid out first. Others have a compression plate. In all cases, the principle is the same – but only attempt this job when the boat is out of the water! Here’s how to repack a stern gland….
1. Unscrew the cap. Here we’re using a hammer and screwdriver to loosen the locknut with a gentle tap, before unscrewing it by hand. A pair of wrenches is a gentler way to loosen it.
2.Remove the old packing. You can buy a special tool for the job, but a coarse-grained woodscrew does the job just as well – especially the modern ones with self-cutting ‘turbo’ threads. A pair of mole grips is perfect for pulling the screw and its packing out.
3. Wrap new packing several times around the shaft and hold it tight. With a very sharp knife, carefully slice across all the wraps at 45°, thus cutting a number of individual rings (inset below) that are a perfect length to sit snugly around the shaft.
4. You can now repack the gland. Put the new packing into the cap, making sure the scarf joints meet. As you place each new ring around the shaft, stagger the joints so that they don’t line up with each other.
5. You can now screw the cap in and tighten it against the locknut. Give the greaser a turn or two to lubricate the bearing. Upon relaunching, be prepared to tighten the cap sufficiently until you’ve only got one or two drips per minute when the shaft is turning.
If you’re fed up with the drips filling up your bilge. why not read our buyer’s guide to dripless shaft seals.