Re: Stus-List testing engine mounts
My sense is that if you have the original mounts it's likely time to replace them. A pry bar under the engine near any of the mounts will give you an idea if the rubber and metal have separated. Rich > On Dec 17, 2013, at 19:15, Eric Frank wrote: > > Is there a good way to test the quality of the engine mounts while Cat's Paw > is on the hard? Last summer, I noticed that when the engine was at full > throttle (about 3000 rpm), water appeared in the bilge. Watching the > dripless prop shaft seal while moving the throttle from mid-speed to full, I > noticed water was spraying out between the carbon piece at the forward end of > the bellows and the SS piece fixed to the shaft. It seemed to me that the > forward end of the bellows was moving forward (have to trust my memory here), > and so the seal leaked. Without analyzing this properly, I thought the > bellows needed to be replaced, which is true, and I ordered a new dripless > seal from PYI and am installing it. > > But after a mention on this list about worn out engine mounts, I realize that > probably the prop shaft and engine were also moving forward because of the > strong thrust of the prop. How else would the front of the bellows move > forward? > > Is there a good way of testing the integrity of the engine mounts while the > boat is on the hard? Obviously now is a good time to replace them if they > are worn out. Is there a way of trying to push the engine forward to see if > I can reproduce what I think I saw? > > Eric Frank > Cat's Paw > C&C 35 Mk II > Mattapoisett, MA > > ___ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com ___ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com
Re: Stus-List testing engine mounts
Eric, There may be another explanation for the water spray. If the PSS shaft seal bellows are not compressed per the installation instructions it is possible for the seal to allow water intrusion. IIRC for Calypso's PSS shaft seal the compression is between 5" and 6". Failed or poor quality engine mounts will also contribute to the change in pressure between the carbon piece and SS rotator. Other than having a friend or boatyard worker push hard on the prop from the outside I am not aware of a standard engine mount test. Observation of the plastic/rubber parts and consideration of their age is what pushed me to change Calypso's. Martin Calypso 1971 C&C 43 Seattle From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Eric Frank Sent: Tuesday, December 17, 2013 3:16 PM To: cnc-list@cnc-list.com Subject: Stus-List testing engine mounts Is there a good way to test the quality of the engine mounts while Cat's Paw is on the hard? Last summer, I noticed that when the engine was at full throttle (about 3000 rpm), water appeared in the bilge. Watching the dripless prop shaft seal while moving the throttle from mid-speed to full, I noticed water was spraying out between the carbon piece at the forward end of the bellows and the SS piece fixed to the shaft. It seemed to me that the forward end of the bellows was moving forward (have to trust my memory here), and so the seal leaked. Without analyzing this properly, I thought the bellows needed to be replaced, which is true, and I ordered a new dripless seal from PYI and am installing it. But after a mention on this list about worn out engine mounts, I realize that probably the prop shaft and engine were also moving forward because of the strong thrust of the prop. How else would the front of the bellows move forward? Is there a good way of testing the integrity of the engine mounts while the boat is on the hard? Obviously now is a good time to replace them if they are worn out. Is there a way of trying to push the engine forward to see if I can reproduce what I think I saw? Eric Frank Cat's Paw C&C 35 Mk II Mattapoisett, MA ___ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com
Re: Stus-List testing engine mounts
Mine were quite bad but I had no idea until I removed them. One of the reasons I used PYI mounts is that they are designed to prevent axial movement, even when worn. I would remove yours one at a time and compare their measurements to that of a new one. Height specifically. You can spot a bad one pretty quick. I'm looking to part with a new spare stock yanmar mount if you find yourself in need. Josh Muckley On Dec 17, 2013 6:15 PM, "Eric Frank" wrote: > Is there a good way to test the quality of the engine mounts while Cat's > Paw is on the hard? Last summer, I noticed that when the engine was at > full throttle (about 3000 rpm), water appeared in the bilge. Watching the > dripless prop shaft seal while moving the throttle from mid-speed to full, > I noticed water was spraying out between the carbon piece at the forward > end of the bellows and the SS piece fixed to the shaft. It seemed to me > that the forward end of the bellows was moving forward (have to trust my > memory here), and so the seal leaked. Without analyzing this properly, I > thought the bellows needed to be replaced, which is true, and I ordered a > new dripless seal from PYI and am installing it. > > But after a mention on this list about worn out engine mounts, I realize > that probably the prop shaft and engine were also moving forward because of > the strong thrust of the prop. How else would the front of the bellows > move forward? > > Is there a good way of testing the integrity of the engine mounts while > the boat is on the hard? Obviously now is a good time to replace them if > they are worn out. Is there a way of trying to push the engine forward to > see if I can reproduce what I think I saw? > > Eric Frank > Cat's Paw > C&C 35 Mk II > Mattapoisett, MA > > > ___ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com > > ___ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com
Stus-List testing engine mounts
Is there a good way to test the quality of the engine mounts while Cat's Paw is on the hard? Last summer, I noticed that when the engine was at full throttle (about 3000 rpm), water appeared in the bilge. Watching the dripless prop shaft seal while moving the throttle from mid-speed to full, I noticed water was spraying out between the carbon piece at the forward end of the bellows and the SS piece fixed to the shaft. It seemed to me that the forward end of the bellows was moving forward (have to trust my memory here), and so the seal leaked. Without analyzing this properly, I thought the bellows needed to be replaced, which is true, and I ordered a new dripless seal from PYI and am installing it. But after a mention on this list about worn out engine mounts, I realize that probably the prop shaft and engine were also moving forward because of the strong thrust of the prop. How else would the front of the bellows move forward? Is there a good way of testing the integrity of the engine mounts while the boat is on the hard? Obviously now is a good time to replace them if they are worn out. Is there a way of trying to push the engine forward to see if I can reproduce what I think I saw? Eric Frank Cat's Paw C&C 35 Mk II Mattapoisett, MA ___ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com CnC-List@cnc-list.com
