Help me Install Dripless Shaft Seal (PYI Model)

[anelso29]

Captains,

Happy Monday! I'm reaching out for some assistance.

I'm currently upgrading and repairing my '84 Hunter 31. As you might understand, one project often leads to another, and before you know it, it feels like you're working on a brand-new boat (just kidding, but seriously).

One of the upgrades I'm tackling is installing a new dripless shaft seal. I opted for a PYI model, which I installed over the weekend. This was my first time installing one, so naturally, I've watched every possible instructional video online to ensure I understand the correct procedure. My boat is currently in dry-dock, making it the perfect time and place to complete the installation.

Attached, you’ll find a a picture with a simple diagram of the work I've done. I would greatly appreciate any feedback to confirm that everything is installed correctly and to ensure that this step alone won’t cause my boat to sink.

There's still plenty to do—I need to install the stainless steel rotor and my new prop shaft, as well as a reservoir for the air tube connected to the dripless (I’ve been unable to find any specific videos on the reservoir part of the process, so I'm considering making one myself). I also need to lift my 2GMF Yanamr engine to install the new prop shaft but also install new engine mounts. Thanks in advance for your insights and support with this undertaking.

NOTE: I understand pictures only go so far and no online reviews or comments can be taken as an official inspection of my work, but all feedback is deeply appreciated.

 

[dlochner]

Tighten the loose hose clamps before you forget. There is not need for them to be loose.

Be certain to add a back up to the SS Rotor. It can be as fancy as a SS collar or as simple a an extra anode. It should be right up against the SS rotor. If for some reason the rotor comes loose the backup will keep it from moving forward and allowing water to leak in.

Do not reuse the set screws and do use locktite.

Expect some spray for the first few hours.

 

[dmax]

And:
Make sure the bellows are compressed the amount specified by PSS, mine is 3/4". This is a pain to do by hand - I made a tool (copied from someone on this site) by grinding out part of a brake caliper expansion tool that, along with the optional but very desirable SS collar Dave mentioned, makes this easy, you can just dial in the compression. Here's an example of the the tool though mine has wider plates, you need to grind out a U in the plates to accommodate the prop shaft:

Amazon.com

 

[capta]

What a wonderful idea these are, except for the fact that if there is a leak in the bellows you are going to have to haul the boat to repair it. When I found this out I decided a little water in the bilge and a packing gland I can repair or work on anywhere, anytime makes a lot more sense to me.

 

[Ralph Johnstone]

I'm currently upgrading and repairing my '84 Hunter 31.

I'm impressed by the immaculately clean area around the shaft and seal given that it's coming into 40 YO.

Remember you have an alignment job coming up once everything is sealed and you are back in the water. That's the real fun, and cussing, and yelling, and swearing, and knuckle scraping,.

 

[dlochner]

I'm impressed by the immaculately clean area around the shaft and seal given that it's coming into 40 YO.

Remember you have an alignment job coming up once everything is sealed and you are back in the water. That's the real fun, and cussing, and yelling, and swearing, and knuckle scraping,.

Spoil Sport!

 

[Ralph Johnstone]

When I found this out I decided a little water in the bilge and a packing gland I can repair or work on anywhere, anytime makes a lot more sense to me.

Can't argue with one word of that. But, the OP is half way there so let's not pi$$ on his parade. They do look nice when installed and running correctly.

However, even if absolutely nothing happens from the install until seven years later when the time for a boot renewal rears it's ugly head, I'd start getting the shakes. The boat's got to be on the dry to work on as opposed to changing out the packing in the water (a Ho-Hum job). Even if you do have a split flange on the prop shaft, how conducive is that to an alignment job when you are looking for an angular alignment of 0.004" maximum on a 4" flange. Put another way, are you guaranteed to keep that 90° angle between the prop shaft axis and the prop shaft flange when the prop shaft flange is re-installed ? Too much drama for this sailor .

A well maintained packing gland should not be a problem if dripping is regulated by gland temperature, which with my packing gland is zero drops when running. The water evaporates off the gland nut before it gets a chance to drip.

 

[Ralph Johnstone]

Spoil Sport!

You feeling a little guilty ?

I figure you can always tell a man's personal hygiene by the cleanliness of his shaft !

 

[heritage]

You asked about a water reservoir for your dripless gland. I routed the air hose up to the top of the engine compartment and then about a foot aft and have never had any water get up that high. I have read that if you back down under high power it can force water up and out of the hose, but so far has never happened to me.

BTW, I have been using the PYI dripless glands on three different boats beginning in 1993. I'm a very happy customer and love the dry bilge.

 

[anelso29]

You asked about a water reservoir for your dripless gland. I routed the air hose up to the top of the engine compartment and then about a foot aft and have never had any water get up that high. I have read that if you back down under high power it can force water up and out of the hose, but so far has never happened to me.

BTW, I have been using the PYI dripless glands on three different boats beginning in 1993. I'm a very happy customer and love the dry bilge.

Thank you for your input and good feedback about the product! I am going to take every step incredibly seriously and I have received a lot of great feedback on this thread.

THANK YOU ALL for your feedback and resources, this is incredibly helpful. I will post more progress pictures once I get further into the project.

 

[dlochner]

This little gadget can help prevent water from coming out of the vent hose when backing up. Some boats have this issue, some don't. This is the link to PYI it is also available elsewhere at another price.

PSS Seal | Hy-Vent

This nickel platted brass vent is to be installed at the end of the vent line. It is a float style vent / valve that will allow air out, however, restrict water flow in that direction.

www.shaftseal.com

 

[anelso29]

This little gadget can help prevent water from coming out of the vent hose when backing up. Some boats have this issue, some don't. This is the link to PYI it is also available elsewhere at another price.

PSS Seal | Hy-Vent

This nickel platted brass vent is to be installed at the end of the vent line. It is a float style vent / valve that will allow air out, however, restrict water flow in that direction.

www.shaftseal.com

This is awesome thank you!!

 

[BAD ORCA]

You don't actually need the water reservoir/hose if you don't want the hassle. I believe this was an adaption designed mainly for high speed power boats. PYI confirmed in an online thread i read some time ago that if you burp your bellows when you back in the water after a haulout, the air vent hose is not needed. It was said that sailboat props do not spin fast enough to create enough heat to be a concern, if i remember correctly. They (PYI) actually sell bolts (plugs) that you can order to plug the hole in the carbon stator. I guess it depends on how easy access is to your shaft seal. Mine is easy to reach and burp.

 

[dlochner]

You don't actually need the water reservoir if you don't want the hassle. I believe this was an adaption designed mainly for high speed power boats. PYI confirmed in an online thread i read some time ago that if you burp your bellows after taking the boat out of the water (haulouts), the air vent hose is not needed. It was said that sailboat props do not spin fast enough to create enough heat to be a concern, if i remember correctly. They (PYI) actually sell bolts (plugs) that you can order to plug the hole in the carbon stator. I guess it depends on how easy access is to your shaft seal. Mine is easy to reach and burp.

PYI used to sell both models, one vented and one unvented. Eventually they dropped the unvented model. The vent is there to avoid having to burp the bellows after launching to ensure water is reaching the graphite bearing. There are 3 issues with the unvented version, 1) The bellows is in an inconvenient place making it difficult to burp, 2) People forget to burp the bellows, and 3) the graphite bearing surface can be damaged when burping. The latter can happen if a screwdriver is used to separate the bellows from the rotor.

Water coming through the vent hose is not a big issue, it just depends on where the hose ends. On my boat the end of the vent hose is above the engine, so water can come up and drop onto a hot engine. Probably not the best place for it, especially if it is salt water.

 

[BAD ORCA]

PYI used to sell both models, one vented and one unvented. Eventually they dropped the unvented model. The vent is there to avoid having to burp the bellows after launching to ensure water is reaching the graphite bearing. There are 3 issues with the unvented version, 1) The bellows is in an inconvenient place making it difficult to burp, 2) People forget to burp the bellows, and 3) the graphite bearing surface can be damaged when burping. The latter can happen if a screwdriver is used to separate the bellows from the rotor.

Water coming through the vent hose is not a big issue, it just depends on where the hose ends. On my boat the end of the vent hose is above the engine, so water can come up and drop onto a hot engine. Probably not the best place for it, especially if it is salt water.

I agree. People who have bad access or dont want to be bothered, this is a useful feature. I can grab my bellows easily with my fingers and pull back on it and burp it. Takes very little effort, but admittedly i have good access.

Check out this video at the 2:10ish mark. Routing the hose should be carefully considered. He was having a problem with the dripless leaking because of the hose routing. The entire video is good actually, albeit a little concerning.

 

[Ralph Johnstone]

Got to remember to lean over and kiss my packing gland next time I pass by it.

 

[Justin_NSA]

You asked about a water reservoir for your dripless gland. I routed the air hose up to the top of the engine compartment and then about a foot aft and have never had any water get up that high. I have read that if you back down under high power it can force water up and out of the hose, but so far has never happened to me.

Same here. I have a LasDrop Gen II dripless and it doesn't call for a reservoir. Just loop the vent line above the waterline

 

[dlochner]

as well as a reservoir for the air tube connected to the dripless (I’ve been unable to find any specific videos on the reservoir part of the process, so I'm considering making one myself).

There is no need for a reservoir. There are some folks who route the vent so that any water that may back up through the vent drips in to a container and not the bilge. The amount of water that backs up through the vent line is measured in teaspoons, not gallons. Some people prefer to capture that water before it gets to the bilge or drips on the engine, the vent line is routed above the water line and then with a 180° bend into a container. This is fine, but unnecessary, so long as the hose goes well above the waterline and there is an air gap before entering the container to prevent a siphon from forming.

The HyVent I linked to earlier is another solution to water backing up into the vent. The concern for water backing up through the vent is really over stated, its not a big problem in freshwater and only a minor problem in salt water if the water drips on to the engine block.

 

[anelso29]

Hey everyone! I’m back with a few more photos. Apologies to the perfectionists out there—I only had a few hours to work this weekend, but here’s what I managed to complete. Following dlochner's advice, I purchased a Hy-Vent, which you can see installed in the pictures below.

I’d love to hear your thoughts and any suggestions for additional adjustments.

Here are a couple of things I still need to address:

• The vent hose needs to be neatly zip-tied along its path.
• The hose clamps on the end of the Hy-Vent need to be tightened.
• All zip ties need to be cleaned up.

Thanks for taking a look!

 

[TimFromLI]

it looks like you have the shaft seal well under control. I would be concerned about getting the shaft coupling aligned to the transmission after changing the mounts and prop shaft.