Drive train noise, stuffing box leak, etc

[LordGothington]

As for tightening the stuffing box further to control drip rate, please revisit my post #6 in this thread. At some point you'll damage the prop shaft. I cannot say you are at that point yet but based on the dialogue I have a sneaky feeling you might be.

Ok. I'll stay another day and repack the stuffing box. (Another first for me!) Pretty sure I can get the flax at the ship store here.

[ndutton]

Cool. Spend some time on the internet to read up on the process like three separate flax rings, joints 120° apart, different types of flax (I've been very pleased with the teflon impregnated flax).

Be sure to use the proper size too. I recommend removing one ring of the old flax and take it with you to buy the replacement. You can reattach the stuffing box with the remaining two rings to check the water inflow while you're away shopping. You'll ship water aboard during the process (a temporary wrap of tape really helps) but it's not much.

When reassembling the stuffing box, start out loose and slowly tighten to your preferred drip rate. No long sleeves when working around a turning shaft.

[Marty Levenson]

stuffing box

I'm always nervous working on the stuffing box in the water. It helps to be sure the bilge pump works and battery good. I also like to have silicone repair tape on hand to wrap it up if needed.

Marty (aka Nervous Nelly)

[ndutton]

Reading assignment including the link roadnsky provided:

http://www.moyermarineforum.com/forums/showthread.php?p=69290

[LordGothington]

I repacked the stuffing box in the water. It's dripping multiple times a second at the moment because I read I am supposed to wait a while before tightening it down so that it can get water logged. I plan to motor around 4 hours tomorrow and then give it some adjustments.

As suspected, my shaft is scorched and scored. So, I'll have to replace that when I next haul it out of the water.

I'll just pretend that this problem already existed when I bought the boat -- which could be true. But there is a reason I bought a cheap (but quality) starter boat to make mistakes with.

Here is a photo of the old stuffing and the shaft. I can feel where the shaft is worn down in spots:

https://photos.app.goo.gl/SkTduWSA4wTCHduBA

What are the side effects of the shaft being warn down? How do I know when it has reached an unsafe amount of wear? I am hoping to do another 650NMi of motoring before my next haul out.

[ndutton]

You're probably correct that this has been going on for a long time but what you are seeing is the direct effect of continually tightening worn out flax attempting to manage drip. With fresh flax you'll be in better shape but do not expect to get an optimal adjustment against a scored shaft. It's gonna drip and if it doesn't you're likely too tight again. On the other hand, you risk nothing with this shaft, the damage has been done. Stuffing box temperature underway is a reliable method to monitor things. Consider 20°F above ambient water temp as the maximum allowable.

[Administrator]

Is there room for a PSS shaft seal?

Bill

[romantic comedy]

LG if you want to continue to be really cheap you might try replacing the packing hose instead of the shaft.

The packing hose is that special wire free, super thick hose that the stuffing box is attached to. The length is arbitrary and can be changed to move the stuffing contact surface to another point on the shaft.

The change can even be done with the boat in the water depending on the access and how confident you are.

[JOHN COOKSON]

LG if you want to continue to be really cheap(????) you might try replacing the packing hose instead of the shaft.
The packing hose is that special wire free, super thick hose that the stuffing box is attached to. The length is arbitrary and can be changed to move the stuffing contact surface to another point on the shaft.
The change can even be done with the boat in the water depending on the access and how confident you are.

I call a maneuver such as this practical not cheap.

TRUE GRIT

[LordGothington]

Is there room for a PSS shaft seal?

Bill

Probably. There is over a foot between the current stuffing box and the engine. And there are a couple inches of free space around it.

[LordGothington]

The length is arbitrary and can be changed to move the stuffing contact surface to another point on the shaft.

The change can even be done with the boat in the water depending on the access and how confident you are.

Hmm. Interesting idea. I am going to have the boat out of the water in a month or so anyway. I assume it is necessary to remove the shaft from the coupler so you can get the old hose off and the new hose on?

I've read that every time you take the coupler off the shaft you have to replace it because of the way it is fit on there? Or switch the the split coupler?

[ndutton]

Plan for the worst, hope for the best

The shaft needs to come out of the coupling for either hose replacement or a PSS seal. There's a better than even chance the shaft will be stuck in the coupling and stuck hard. There is a method found on this forum to press it out in situ but it risks destroying the engine output coupling in the process. Before going that far many prefer to cut the shaft between the coupling and the stuffing box and then extract the stump from the coupling with a shop press. Of course at that point you are in for a new shaft.

[LordGothington]

Of course at that point you are in for a new shaft.

Truthfully, I'll probably put in a new shaft regardless. I am having a harder time deciding on the PSS.

On the one hand, the PSS sounded like a good idea when I feared the stuffing box. But now that I am less fearful of it, I am more worried about the PSS. I've heard rumors it works great until it suddenly doesn't work at all.

While not comfortable, I *can* get both hands on my stuffing box. And I have gotten quite good at making the adjustments. I can even repack it in the water now

I guess I have a month to decide.

[romantic comedy]

Hmm. Interesting idea. I am going to have the boat out of the water in a month or so anyway. I assume it is necessary to remove the shaft from the coupler so you can get the old hose off and the new hose on?

I've read that every time you take the coupler off the shaft you have to replace it because of the way it is fit on there? Or switch the the split coupler?

I take the coupling off the shaft twice a year. That would make that over 40 times with the same shaft and coupling. The reason is that I have a diver do the bottom. I have him pull the shaft, give to me to clean the prop, then do the bottom. It usually takes me just as long to clean the prop as it takes for him to do the bottom. Then he puts the shaft back in and all is clean.

Also when the boat is in the yard I pull the shaft to make bottom work easier.

But if your shaft and coupling have become one you may have to steer a different course.

[LordGothington]

I take the coupling off the shaft twice a year. That would make that over 40 times with the same shaft and coupling.

All I know is that *some people* claim that the 'press fit' shaft coupling can only be used once. And that if you use it multiple times, then you risk having the propeller shoot out the back of the boat when you put it in reverse. Hence the invention of the split coupler that is designed to be reused.

Maybe *some people* are wrong. I have no first hand experience

I have no idea when this shaft and coupler were mated. At least a decade ago I'd guess.