Ian_Edwards
Well-Known Member
Some comments on Stern Glands and Cutlass Bearings, which may assist some of the recent postings.
I had the problem of an over heating or leaking stern gland, I could never get the balance right and spent a lot of time tightening or loosening the nut on the end of the packing gland and injecting grease. I solve the problem with a PSS seal which runs a carbon block onto a stainless steel block, no leak, no over heating, problem solved. However you need to take care because the PSS seal MUST be water lubricated and since my boat dries twice a day, I fitted a version designed for high speed shafts. This has a hose connection (originally for forcing water into the stern tube) I simply fitted a long hose which I brought up well above the water line (inside the cockpit locker) which acts as a vent. I’ve used this successfully for 6 years now.
Next, I found that all that grease I’d pumped in over the years was still in the stern tube, some where between the stern gland and the cutlass bearing and a congealed mass! This caused the cutlass bearing and the prop shaft the wear very quickly. The grease held the gritty mud firmly in place, which in effect, acted like sandpaper. The cutlass bearing and the bit of the shaft which is associated with it where particularly effected. It took about 0.5mm of the SS shaft in less than a season. So I had to replace both the shaft and the bearing!
By accident (whilst cleaning the old grease out of the stern tube) I discovered that if I remove the prop shaft and reversed it, so that the thread which hold the prop on was in-board and I fitted the prop nut, then slid it back down the shaft, the nut caught on the brass outer ring of the cutlass bearing. I could now use the shaft like a slide hammer and gently tap out the cutlass bearing, after loosening the retaining grub screws. Easy, the old bearing came out without a problem.
So the moral of the story … if there is indeed one, is don’t over grease your stuffing gland, use a PSS seal but keep it wet and always reverse your shaft to get the cutlass bearing out!
Happy sailing, and cheers, Ian.
I had the problem of an over heating or leaking stern gland, I could never get the balance right and spent a lot of time tightening or loosening the nut on the end of the packing gland and injecting grease. I solve the problem with a PSS seal which runs a carbon block onto a stainless steel block, no leak, no over heating, problem solved. However you need to take care because the PSS seal MUST be water lubricated and since my boat dries twice a day, I fitted a version designed for high speed shafts. This has a hose connection (originally for forcing water into the stern tube) I simply fitted a long hose which I brought up well above the water line (inside the cockpit locker) which acts as a vent. I’ve used this successfully for 6 years now.
Next, I found that all that grease I’d pumped in over the years was still in the stern tube, some where between the stern gland and the cutlass bearing and a congealed mass! This caused the cutlass bearing and the prop shaft the wear very quickly. The grease held the gritty mud firmly in place, which in effect, acted like sandpaper. The cutlass bearing and the bit of the shaft which is associated with it where particularly effected. It took about 0.5mm of the SS shaft in less than a season. So I had to replace both the shaft and the bearing!
By accident (whilst cleaning the old grease out of the stern tube) I discovered that if I remove the prop shaft and reversed it, so that the thread which hold the prop on was in-board and I fitted the prop nut, then slid it back down the shaft, the nut caught on the brass outer ring of the cutlass bearing. I could now use the shaft like a slide hammer and gently tap out the cutlass bearing, after loosening the retaining grub screws. Easy, the old bearing came out without a problem.
So the moral of the story … if there is indeed one, is don’t over grease your stuffing gland, use a PSS seal but keep it wet and always reverse your shaft to get the cutlass bearing out!
Happy sailing, and cheers, Ian.
