Photographed stern tube, stuffing box. I'm taking on a bilge full of water every week. I posted the attached photos on the Viking 33_34 user's group and received the following...

Has anyone adjusted their stuffing box / stern tube while in the water? I'm shipping a bilge full of water a week. Any advice?

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I have both adjusted / replaced the packing while our boat is in the water.   Then again with our boat being in our family for over 35 years I have serviced just about anything that can be serviced on it.  

From the looks of things your boat resides in salt water.   You have corrosion on the packing gland and on the shaft flange.   This makes me sort of happy to be sailing in fresh water - our packing gland looks like the day I installed it.  It looks like your boat is fit with a Yanmar diesel engine.     

The first thing is can you back off the keeper nut from your packing gland.   On yours you will need two appropriate sized pipe wrenches.  Put some penetrating oil on the packing gland - be liberal in use because things look pretty ugly there in terms of corrosion.   Let me warn you that it is not a lot of fun to work on this gland with two wrenches - I would suggest also having a small sledge hammer or ball pean hammer - to break away the nut with a sharp blow on impact.    Once the keeper nut is backed off then you can tighten the packing gland until the dripping just stops at rest.   Then with the engine in neutral you have to check for the free rotation of the shaft.  If it does rotates freely you are good if it does NOT freely rotate - then the packing must be replaced.  If you over tighten the shaft - you will score the stainless shaft and damage it or even stall out the engine and do damage - the shaft must be able to rotate pretty easily.  

Before you back off the packing gland you need to prepare three lengths of packing - for a Viking 33 the size is 1/4” packing and it comes in two basic types one lead impregnated - old school and also teflon impregnated - new school.   You need to do one wrap tightly around the shaft and use a razor blade on an angle to get one wrap done.    You again will need three of these to replace the packing. 

You need to fabricate a tool like a skate lace tighter or a piece of stout coat hanger with a small hook on the end to pull out the old packing. 

When you back off the nut - off of the gland water will gush into the boat.   It comes in pretty quickly, while this happens you need to pull out all the old packing from the gland and I mean all of it.   You may need to have an auto bilge pump running while you do this.   After the old packing is out then you need to insert one wrap and set it in place gently with the packing nut, then back off the nut and set the second wrap in and put it in place with the packing nut, then do the same thing with the third wrap.  Tighten until water just stops dripping.  Set the keeper nut back in place and then run the boat for a bit and recheck the packing and it will need adjusting after running the boat a bit - set the pressure carefully and you will get years out of it - do it wrong and you can spend a lot of money.   Shaft work is not inexpensive. 

If you need to ask a question then feel free to call me. 

Dan Erlich
 

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Oh before you start - measure the packing nut length to see if you can back it off enough with the amount of shaft you have exposed FIRST - yours looks very tight - you may very well not have enough room to replace the packing with this amount of room - this happens to be the case in our boat.   I know this is the case in OUR boat and it looks like it is the case in yours from the picture.    You need the nut length plus about one inch or more to be able to dig the old packing out of that gland.    I would be very certain of the measurements before you start this job.    

Then it becomes far more complicated because the ENGINE must come off the shaft and be placed in the boat so the shaft can be pulled back and into the boat before the nut can back off enough to service the gland.  

Believe it or not - I have to do this to change the packing on our boat - I have to take the engine out - I do this by myself and while it is time consuming it is not that big a deal.  In your case with the corrosion on the rear flange it might be quite an ordeal to remove the hardware from the flange to do this.   You will need to use a liberal amount of penetrating oil and a lot of patience.  

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Thanks so much for the invaluable information Dan. Our boat too has been in our family for 35 years. My father has dementia so he can't tell me if he's ever done it. It is not mentioned in the ship's log.

I'm ok with everything you said EXCEPT the part about the water gushing in. That gives me nightmares.
I'm not due to pull her out until November but not sure if I can ignore the water until then.

Maybe I'll try freeing it and tightening it...

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Great info Dan. How long does the Teflon packing last in fresh water?

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I had Teflon packing in my stuffing box without incident until my coupling failed.   When I pulled the shaft and switched it out to a Vetus coupling I changed the packing then.   That has been say seven seasons at perhaps 60 hours per season so far.  I don't know how long it will still last. 

A shaft should be burnished with Emory cloth to take the shiny polished surface off of it at the packing gland.  To leave it polished will reduce the seal life.  This is best practice.  Thing is the only way to do this is to pull the engine out so it does not always happen.  I coated the manifold bolts and the coupling fasteners with never seize so I can more easily disassemble and pull the engine when I need to do so.

I can adjust my stuffing box but I can not change out the packing without pulling the engine.   For me this entails about five to six hours of work from start to finish. 

I can and do this in the water.  If need be get a house sump pump to deal wth the water flow while you work.  They give you great piece of mind as the water gushes in.   Once you do it then it is a calmer experience the second time round.   Experience is a good teacher. 

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You may find this of help. Four "rings" of 1/4" packing have worked quite well:

http://alchemy2009.blogspot.ca/2013/08/getting-stuffed-guide.html

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I didn't want to do mine by myself when I first got the boat. Now that I watched the pro's do it, I would have no hesitation.Your additional tips are great and I'll be using them. I can get to my stuffing box fairly easily so I may replace it this weekend will its still on the hard.

I'm getting the boat out of the warehouse today and should be floating again within a week.