One chore that I could not put off anymore was the replacement of the packing material in the gland that the propellor shaft runs through. After the engine rebuild in Carrabbelle the shaft had been pushed in and out of the gland a couple of times and though it was ok when we left, the gland began leaking more and more as we moved south. I had tightened it a couple of times but now it was tightened as tight as it could go and as we pulled into Salinas the water was now spraying a fine mist through the gland into the engine compartment so it was time to get it replaced in this calm anchorage.
The packing gland is an interesting part of the boat as the propellor shaft is rotating at a lot of rpm’s though this bearing. They have solved the friction/heating problem by allowing the bearing to “leak”, passing a small amount of water from the outside through the bearing to cool the shaft of the friction. Normally the gland is supposed to leak at a rate of 3 drops per minute. Hard to imagine that this would cool the bearing, but whatever! This water eventually makes it way to the bilge where it is pumped out by the bilge pump.
I had not done this before and spent a little time on You-tube and other media formats to get a better idea on how to complete this job without sinking the boat. You see, when you back off the gland bolt you open up a hole in the bottom of the boat where the shaft runs through and you do your work while the boat is sinking (kind of). I had been doing everything I could to avoid dealing with this problem.
I was able to get Sim from Wandering Star to come over to help me. I bought the packing from West Marine, got a tank from Vagabond and went under the boat to try to block up as much of the opening from the outside as possible. I cleared the back room and rear engine compartment to give us all the room I could and we began to undo the packing gland bolt. Luckily Sim was a marine engineer (a real one, not one like me!) and spent years in the lower decks of all kinds of major vessels from tankers to large training sailboats. We began pulling the gland and found that my exercise of blocking the flow from the outside was for naught as water began gushing (a technical term) into the engine compartment. Sim calmly took a tee shirt and some zip ties and we wrapped the shaft and slowed the onslaught to a dribble, our bilge pump began it’s job and now easily kept up with this small flow (a side bar on the bilge pump to follow).
It seems that there is a special tool to remove the old packing, a corkscrew like device that you screw into the old material to yank it out. I certainly did not have one but Sim had brought over the tool that he got from Scott on Symbiosis who knew I was going to be doing this work and had dropped it off on Sim’s boat. It takes a Village!
With a little effort we were able to remove and clean out the old material and gland and using a trick (it seems there is always a trick) of hammering one face of the packing material to make it thinner and and easier to install into the packing gland we were able to get the new material into the gland. We undid the teeshirt and with water streaming into the boat again (somehow this does not feel like a good way to do this kind of work) were were able to rethread the gland.
The packing gland is an interesting part of the boat as the propellor shaft is rotating at a lot of rpm’s though this bearing. They have solved the friction/heating problem by allowing the bearing to “leak”, passing a small amount of water from the outside through the bearing to cool the shaft of the friction. Normally the gland is supposed to leak at a rate of 3 drops per minute. Hard to imagine that this would cool the bearing, but whatever! This water eventually makes it way to the bilge where it is pumped out by the bilge pump.
I had not done this before and spent a little time on You-tube and other media formats to get a better idea on how to complete this job without sinking the boat. You see, when you back off the gland bolt you open up a hole in the bottom of the boat where the shaft runs through and you do your work while the boat is sinking (kind of). I had been doing everything I could to avoid dealing with this problem.
I was able to get Sim from Wandering Star to come over to help me. I bought the packing from West Marine, got a tank from Vagabond and went under the boat to try to block up as much of the opening from the outside as possible. I cleared the back room and rear engine compartment to give us all the room I could and we began to undo the packing gland bolt. Luckily Sim was a marine engineer (a real one, not one like me!) and spent years in the lower decks of all kinds of major vessels from tankers to large training sailboats. We began pulling the gland and found that my exercise of blocking the flow from the outside was for naught as water began gushing (a technical term) into the engine compartment. Sim calmly took a tee shirt and some zip ties and we wrapped the shaft and slowed the onslaught to a dribble, our bilge pump began it’s job and now easily kept up with this small flow (a side bar on the bilge pump to follow).
It seems that there is a special tool to remove the old packing, a corkscrew like device that you screw into the old material to yank it out. I certainly did not have one but Sim had brought over the tool that he got from Scott on Symbiosis who knew I was going to be doing this work and had dropped it off on Sim’s boat. It takes a Village!
With a little effort we were able to remove and clean out the old material and gland and using a trick (it seems there is always a trick) of hammering one face of the packing material to make it thinner and and easier to install into the packing gland we were able to get the new material into the gland. We undid the teeshirt and with water streaming into the boat again (somehow this does not feel like a good way to do this kind of work) were were able to rethread the gland.
This seem like it should be the end of the story however….. Over the next day or so we had exercised the engine and put some load on the propellor shaft by running it at anchor, mostly in reverse. We had adjusted the gland and it seemed everything was working as it should. The next day a sailboat anchored very close to us as while we were ashore. We worried that we could swing into each other but the anchorage was protected, there was no wind and none expected so we let it go. At about 1 am we heard this terrible crash and rushed on deck to see the bow sprint of this boat rake across our stern! We later found that they had done some minor damage to our stern rail and a fishing pole, fortunately that was all. We tried to talk to the other boat with a “we don’t speak english” response. We pulled anchor to move out of “their way” and as we set the anchor upwind in a clear spot in the harbor Danielle asked why is the bilge on, a quick examination and we found that the gland had backed off the shaft and water was now again flowing into the bilge. Danielle and I worked together get the gland back on and tightened on the threads to avert the pending catastrophe. Nothing like an anchor drill in the middle of the night to get your heart racing and adrenaline up. Needless to say we sat up for the next couple of hours.
With daylight we surmised that the locking ring was not tightened completely and while the shaft was going in reverse it was putting pressure in the correct direction to keep the gland screwed tight. When we went into forward to reset the anchor the motion of the shaft slowly unwound the gland and it unscrewed itself away from the locking ring that was not tight enough and then off the shaft. Needless to say we spent the morning retightening the shaft and motoring out of the anchorage to test the connection and the locking ring! All has been well since leaving Salinas last month.
Side bar - Sometimes your actions are predicated premonition and this repair scenario was just such a case. As I knew that we would be changing the packing I tested the bilge pump system including the float switch. Now the float switch and pump had been working fine since we bought the boat in 2012 so there was no real reason to expect a problem however when I tested the switch it did not engage the pump. I filled the bilge with water and the switch lifted (floated) but did not engage the bilge….. The manual button on the console worked just fine so we knew the pump was working. Sim happened by the boat to look at the transmission gland prior to beginning that work and saw me struggling. We tested all the components and found each component in order so I thought it was just a bad connection. As I began putting the system all back together, testing each new connection I was not able to get the switch to engage the pump. I cut out old line and rewired the entire run, still nothing. Three hours later and I still did not have a functioning bilge and Sim was now sitting in the cockpit laughing at me. “I left you with a 10 minute job and you are still at it”. Seems that the switch worked but the wires were so bad that they could not carry the electrical load anymore. I had bought a replacement switch and pump before the trip and when I installed the new switch it worked perfectly…. whew! I can just imagine what would have happened if the bilge pump switch was not working when we began changed the packing gland. Sometimes I think you just know that something is wrong ahead of time.
With daylight we surmised that the locking ring was not tightened completely and while the shaft was going in reverse it was putting pressure in the correct direction to keep the gland screwed tight. When we went into forward to reset the anchor the motion of the shaft slowly unwound the gland and it unscrewed itself away from the locking ring that was not tight enough and then off the shaft. Needless to say we spent the morning retightening the shaft and motoring out of the anchorage to test the connection and the locking ring! All has been well since leaving Salinas last month.
Side bar - Sometimes your actions are predicated premonition and this repair scenario was just such a case. As I knew that we would be changing the packing I tested the bilge pump system including the float switch. Now the float switch and pump had been working fine since we bought the boat in 2012 so there was no real reason to expect a problem however when I tested the switch it did not engage the pump. I filled the bilge with water and the switch lifted (floated) but did not engage the bilge….. The manual button on the console worked just fine so we knew the pump was working. Sim happened by the boat to look at the transmission gland prior to beginning that work and saw me struggling. We tested all the components and found each component in order so I thought it was just a bad connection. As I began putting the system all back together, testing each new connection I was not able to get the switch to engage the pump. I cut out old line and rewired the entire run, still nothing. Three hours later and I still did not have a functioning bilge and Sim was now sitting in the cockpit laughing at me. “I left you with a 10 minute job and you are still at it”. Seems that the switch worked but the wires were so bad that they could not carry the electrical load anymore. I had bought a replacement switch and pump before the trip and when I installed the new switch it worked perfectly…. whew! I can just imagine what would have happened if the bilge pump switch was not working when we began changed the packing gland. Sometimes I think you just know that something is wrong ahead of time.
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