The dealer that we bought the new Yanmar2GM20F from recommended against using the PYI seal system with this engine because he reported that the current engine mounts are so flexible that the springs in the seal sometimes have a problem keeping adequate contact.
I spoke with a PYI rep about the and he suggested precompressing the springs more than usual. When I did not seem too impressed with this idea, he then told me the they manufacture more rigid engine mounts for this engine. @ $2xx per set. This sort of ended the discussion. I am now at the point I either have to buy a new suffing box ass'y, (the old one, I find, a bit more corroded that I like), or go with something else.
I would be grateful for others experiences.
Jim
jtstull@earthlink.net
PYI shaft seal
Moderator: Jim Walsh
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Warren Kaplan
Re: PYI shaft seal
Jim,Jim Stull wrote: The dealer that we bought the new Yanmar2GM20F from recommended against using the PYI seal system with this engine because he reported that the current engine mounts are so flexible that the springs in the seal sometimes have a problem keeping adequate contact.
I spoke with a PYI rep about the and he suggested precompressing the springs more than usual. When I did not seem too impressed with this idea, he then told me the they manufacture more rigid engine mounts for this engine. @ $2xx per set. This sort of ended the discussion. I am now at the point I either have to buy a new suffing box ass'y, (the old one, I find, a bit more corroded that I like), or go with something else.
I would be grateful for others experiences.
Jim
I don't know that I can help you with any of the technical stuff you are asking about, but I did replace the stuffing box on my 1980 CD27 last year with the PYI shaft seal. Worked great all last year. I did get the high speed shaft seal even though my low speed Cape Dory 27 doesn't require it. The high speed has a hose that comes off the water intake of the engine and leads right into the seal, providing constant water for lubrication and cooling. The standard has no such hose and water gets into the seal "passively". The high speed seal cost a few bucks more and to my mind was worth the cost. I don't know if this help but there it is.
Warren Kaplan
Sine Qua Non
CD27
Setsail728@aol.com
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Mike
Re: PYI shaft seal
Jim:
I replaced my worn out, leaking stuffing box with a PYI shaft seal on my cd25d. It's the best thing I ever did. No leak, no wear. It just makes sense. I have the Yanmar 1GM, so the vibration issue would seem to be a bigger problem for me with the "one banger". The guys at PYI were very helpful, so I would defer to their knowlege base concerning vibration/motor mounts.
If you price them, I found Sailnet was about $70.oo cheaper than West Marine. While you're at it, replace the cutlas bearing at the same time, this should also help with any alignment issues.
Good Luck, if you need any advise on changing it out, don't hesitate to drop me an e-mail.
Mike
mwankum@tribune.com
I replaced my worn out, leaking stuffing box with a PYI shaft seal on my cd25d. It's the best thing I ever did. No leak, no wear. It just makes sense. I have the Yanmar 1GM, so the vibration issue would seem to be a bigger problem for me with the "one banger". The guys at PYI were very helpful, so I would defer to their knowlege base concerning vibration/motor mounts.
If you price them, I found Sailnet was about $70.oo cheaper than West Marine. While you're at it, replace the cutlas bearing at the same time, this should also help with any alignment issues.
Good Luck, if you need any advise on changing it out, don't hesitate to drop me an e-mail.
Mike
mwankum@tribune.com
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Serge Zimberoff
Re: PYI shaft seal
Also get the March/April issue of 'Good Old Boat' magazine. Detailed article on stuffing boxes including comparisons and hands-on tips. Very well presented with cut-away drawings etc. Could be very timely for your project.
serge@srtrop.com
serge@srtrop.com
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Jim Stull
Re: PYI shaft seal
Thanks for the heads-up. I just finished reading this.
Jim
Jtstull@ earthlinl.net
Jim
Jtstull@ earthlinl.net
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Jim Stull
Re: PYI shaft seal
Thanks for the help Mike.
As I understand what the Yanmar guy was telling me was that the new engine mounts were VERY flexible. The concept being that the engine would "wobble" around on the mounts but not transmit the "thumping" to the hull.
This "wobbling", might allow the two faces of the seal to part company at times. Thus allow leakage. I sort of took this with a grain of salt when I heard this and expected the PYI guy (at the Anapolis Show last fall), to say that this was untrue. He waffled! Maybe I had the wrong PYI guy. I will call the factory.
I have the new cutless brg on hand. Any special tips on installation. What type of sealant did you use?
Jim
jtstull@earthlik.net
As I understand what the Yanmar guy was telling me was that the new engine mounts were VERY flexible. The concept being that the engine would "wobble" around on the mounts but not transmit the "thumping" to the hull.
This "wobbling", might allow the two faces of the seal to part company at times. Thus allow leakage. I sort of took this with a grain of salt when I heard this and expected the PYI guy (at the Anapolis Show last fall), to say that this was untrue. He waffled! Maybe I had the wrong PYI guy. I will call the factory.
I have the new cutless brg on hand. Any special tips on installation. What type of sealant did you use?
Jim
jtstull@earthlik.net
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Jim Stull
Re: PYI shaft seal
Thanks for the info Warren.
I have forgotten which engine you have in your boat.
Jim
jtstull @ earthlink.net
I have forgotten which engine you have in your boat.
Jim
jtstull @ earthlink.net
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len
Re: PYI shaft seal
jim
i've had to use a lubricant, not a sealant, to get the cutlass bearing all the way in - it's held in place with cone-pointed set screws, they have an allen wrench head - drill and tap two, 180 degrees apart, near the aft end of the fiberglass that will hold the bearing, then fiberglass over the screws - it's good to drill a little way into the brass sleeve of the bearing, just enough so the set screw has something to go into it - generally it will be so tight, if you ever have to remove it, you have to slice it lengthwise to get it out
len
md.frel@nwh.org
i've had to use a lubricant, not a sealant, to get the cutlass bearing all the way in - it's held in place with cone-pointed set screws, they have an allen wrench head - drill and tap two, 180 degrees apart, near the aft end of the fiberglass that will hold the bearing, then fiberglass over the screws - it's good to drill a little way into the brass sleeve of the bearing, just enough so the set screw has something to go into it - generally it will be so tight, if you ever have to remove it, you have to slice it lengthwise to get it out
len
md.frel@nwh.org
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John R.
Re: PYI shaft seal
I've installed my share of shaft seals over the years and I believe the PYI / PSS is the best seal. We all know any inboard engine moves quite a bit when under thrust in a forward motion. I am skeptical about what this dealer is telling you. He claims more flexible mounts as being a problem, I doubt it. How much can an engine mount move in theory anyway and still keep all components in alignment? If those mounts allow enough movement to affect a flexible shaft seal then I'd hate to think about what it would be doing to a cutless! Something just doesn't make sense about what he is telling you.
If you increase the seal tension you should have no problems as the PYI rep suggests. Remeber those seals can accomodate quite a bit of movement. If the mounts are as flexible as he implies I would be more worried about the stresses placed upon the stern tube hose and clamp security.
If I were you I would have a discussion with a major Yanmar distributor about those mounts and get their feedback from what they have been told by multiple dealers. Get some specs on range of maximum motion, Yanmar is good about having that information available, just look in the back of a service manual.
It's not unusual practice to apply more tension on shaft seals by increasing the bellows compression. Only do that with fabric reinforced bellows units. I believe the PYI bellows is nitrile and that is then of no concern. Remember water pressure is also a factor in maintaining seal compression along with the bellows.
If you increase the seal tension you should have no problems as the PYI rep suggests. Remeber those seals can accomodate quite a bit of movement. If the mounts are as flexible as he implies I would be more worried about the stresses placed upon the stern tube hose and clamp security.
If I were you I would have a discussion with a major Yanmar distributor about those mounts and get their feedback from what they have been told by multiple dealers. Get some specs on range of maximum motion, Yanmar is good about having that information available, just look in the back of a service manual.
It's not unusual practice to apply more tension on shaft seals by increasing the bellows compression. Only do that with fabric reinforced bellows units. I believe the PYI bellows is nitrile and that is then of no concern. Remember water pressure is also a factor in maintaining seal compression along with the bellows.
Jim Stull wrote: The dealer that we bought the new Yanmar2GM20F from recommended against using the PYI seal system with this engine because he reported that the current engine mounts are so flexible that the springs in the seal sometimes have a problem keeping adequate contact.
I spoke with a PYI rep about the and he suggested precompressing the springs more than usual. When I did not seem too impressed with this idea, he then told me the they manufacture more rigid engine mounts for this engine. @ $2xx per set. This sort of ended the discussion. I am now at the point I either have to buy a new suffing box ass'y, (the old one, I find, a bit more corroded that I like), or go with something else.
I would be grateful for others experiences.
Jim
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Boyd
Re: PYI shaft seal
Hi Jim...
I looked long and hard at a PYI seal to replace my eternally dripping stuffing box. However comparing the price to what a package of the green no drip stuffing box compound that they sell at West convinced me to wait on the PYI for a year or so... Best thing I ever did. The green packing is great. No drips and the box runs cool all the time.
I took out the old stuffing box and soaked it in vinegar. Buffed it with a wire wheel and it looks new. New hose section and I got a great solution at very little expense. Maybe some day I will get one of those expensive seals but not for now.
Boyd
Tern30@aol.com
I looked long and hard at a PYI seal to replace my eternally dripping stuffing box. However comparing the price to what a package of the green no drip stuffing box compound that they sell at West convinced me to wait on the PYI for a year or so... Best thing I ever did. The green packing is great. No drips and the box runs cool all the time.
I took out the old stuffing box and soaked it in vinegar. Buffed it with a wire wheel and it looks new. New hose section and I got a great solution at very little expense. Maybe some day I will get one of those expensive seals but not for now.
Boyd
Jim Stull wrote: The dealer that we bought the new Yanmar2GM20F from recommended against using the PYI seal system with this engine because he reported that the current engine mounts are so flexible that the springs in the seal sometimes have a problem keeping adequate contact.
I spoke with a PYI rep about the and he suggested precompressing the springs more than usual. When I did not seem too impressed with this idea, he then told me the they manufacture more rigid engine mounts for this engine. @ $2xx per set. This sort of ended the discussion. I am now at the point I either have to buy a new suffing box ass'y, (the old one, I find, a bit more corroded that I like), or go with something else.
I would be grateful for others experiences.
Jim
Tern30@aol.com