Fw: vibration/alignment

resending in case you missed how to align the shaft at the coupler, Helen ----- Forwarded Message ---- From: Helen Horn <he… [at] sbcglobal.net> To: Ca… [at] yahoogroups.com Sent: Sun, January 9, 2011 10:56:55 PM Subject: vibration/alignment Have you had a diver check your prop or cutlass bearing, you could have a damaged prop(bent or even missing a blade or part of one) which could vibrate to the point your cutlass gets worn badly, then everything could be flopping around and the main receiver of all this would be that coupler. Have you hauled your boat and checked the shaft, it could be slightly bent? A diver can grab the prop blade and shake it and check for worn out cutlass bearing, it should be snug and have no play. Also, your prop may have struck something, and perhaps your strut is bent(if you have one). Just some things I've observed at boatyards, and even after you haul a boat and do shaft work you put the boat in the water and do an alignment 24 hours later after the hull has resumed its waterborn shape. There should be no vibrations after that, or you do the alignment until you get it right. The coupling between the engine and the dampener should be within .002 when you disconnect them. (the shaft has to be checked to be sure it is not moving) Then you adjust your engine to correct the alignment. It would be good to check this before you harm your engine or yourself..... Helen (p.s. one time a commercial salmon boat I half-owned had wrapped a piece (long piece) of polypro line from some lost crabpot around the shaft between the prop and the bearing and it melted on hard and luckily got diagnosed before it pulled that prop shaft right out of the boat.)

I think this is excellent advice. Having just gone through removing a bad vibration by aligning the engine I will elaborate on the advice Helen is giving. The test for alignment is between the engine and the shaft. It is measured on the coupling flange at the outer edge of the flange. What I did was unbolt the flange and pull it back from the engine a bit. Take a feeler gauge, say 0.020 and press the prop shaft back up to the engine with the gauge between so you know that there is 0.020 between them. Have the gauge on the top. Then see what gauge fits on the bottom and the sides. They should be close to 0.020. Helen says 0.002 so that would mean that a gauge between 0.018 and 0.022 is the same fit as the 0.020 gauge on top. I think I used a guideline of 0.003 but in any case as I started with a difference of 0.014 so I had a problem. To fix the problem I moved the engine up on the forward motor mounts and over toward port. Oh, I forgot. Take the prop flange and move it athwardship as well as up and down. The flange should be more or less centered. Mine wasn't so I moved the engine a bit to port. Moving the forward end of the engine up moved the flange down and that helped in my case. You can calculate how much you have to move the engine based on the distance from the motor mounts and the output flange. I drew it up on Google Sketchup and used the measurements from that. I removed the old lag bolts that were holding the motor mounts down. Three came out and one broke. I had to epoxy some wood to extend where the mount was so that I could drill a new hole for the aft mount. Hopefully your bolts will come out without issue. I hope this helps. I googled marine engine alignment and mostly I don't like the articles that come up so I can't recommend any of them. They seem to be talking about something other than what applies to me, and likely to you as well. This picture may help though. Just use a feeler gauge instead of the tissue: http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif <http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif>Allen On Tue, Jan 11, 2011 at 6:39 PM, Helen Horn <he… [at] sbcglobal.net> wrote: > resending in case you missed how to align the shaft at the coupler, Helen > > ----- Forwarded Message ---- > *From:* Helen Horn <he… [at] sbcglobal.net> > *To:* Ca… [at] yahoogroups.com > *Sent:* Sun, January 9, 2011 10:56:55 PM > *Subject:* vibration/alignment > > > Have you had a diver check your prop or cutlass bearing, you could have a > damaged prop(bent or even missing a blade or part of one) which could > vibrate to the point your cutlass gets worn badly, then everything could be > flopping around and the main receiver of all this would be that coupler. > Have you hauled your boat and checked the shaft, it could be slightly bent? > A diver can grab the prop blade and shake it and check for worn out cutlass > bearing, it should be snug and have no play. Also, your prop may have struck > something, and perhaps your strut is bent(if you have one). Just some things > I've observed at boatyards, and even after you haul a boat and do shaft work > you put the boat in the water and do an alignment 24 hours later after the > hull has resumed its waterborn shape. There should be no vibrations after > that, or you do the alignment until you get it right. The coupling between > the engine and the dampener should be within .002 when you disconnect them. > (the shaft has to be checked to be sure it is not moving) Then you adjust > your engine to correct the alignment. It would be good to check this before > you harm your engine or yourself..... Helen (p.s. one time a commercial > salmon boat I half-owned had wrapped a piece (long piece) of polypro line > from some lost crabpot around the shaft between the prop and the bearing and > it melted on hard and luckily got diagnosed before it pulled that prop shaft > right out of the boat.) > > > >

Hi Allen, I also use Google Sketchup, would you be willing the share the document you created with me/us? I think it would be helpful in my trying to understand what I'm dealing with. I called a mechanic this week to just talk through this stuff and see if I should have someone come look at it or if I can handle the issues my self. He said something interesting about the large rubber "coupler" (not sure what to call it). He mentioned that because of it's flexibility the engine does not need to be aligned as well as an engine with stiff mounts (do any engines have truly stiff mounts?). I'm having a hard time believing him, and am thinking that the closer alignment I can get the better. Frans mentioned,"The rubber coupler you were referring to is not designed to dampen engine vibration, it is designed to absorb torsional strain in the shaft as it rotates." What is the benefit of this? Less strain on the transmission? Do most inboards have this? Is it located in the same part of the shaft (between the trans fange and the shaft flange)? I am looking in to the Auquadrive system. (http://www.aquadrive.net/) Does anyone have one installed that can give feedback? Worth the investment? Is it really as effective as they say? (95% less vibration and 50% less noise).. All very helfpul, thanks! Matt --- In Ca… [at] yahoogroups.com, Allen Edwards <allen.edwards@...> wrote: > > I think this is excellent advice. Having just gone through removing a bad > vibration by aligning the engine I will elaborate on the advice Helen is > giving. > > The test for alignment is between the engine and the shaft. It is measured > on the coupling flange at the outer edge of the flange. What I did was > unbolt the flange and pull it back from the engine a bit. Take a feeler > gauge, say 0.020 and press the prop shaft back up to the engine with the > gauge between so you know that there is 0.020 between them. Have the gauge > on the top. Then see what gauge fits on the bottom and the sides. They > should be close to 0.020. Helen says 0.002 so that would mean that a gauge > between 0.018 and 0.022 is the same fit as the 0.020 gauge on top. I think > I used a guideline of 0.003 but in any case as I started with a difference > of 0.014 so I had a problem. To fix the problem I moved the engine up on > the forward motor mounts and over toward port. Oh, I forgot. Take the prop > flange and move it athwardship as well as up and down. The flange should be > more or less centered. Mine wasn't so I moved the engine a bit to port. > Moving the forward end of the engine up moved the flange down and that > helped in my case. You can calculate how much you have to move the engine > based on the distance from the motor mounts and the output flange. I drew > it up on Google Sketchup and used the measurements from that. I removed the > old lag bolts that were holding the motor mounts down. Three came out and > one broke. I had to epoxy some wood to extend where the mount was so that I > could drill a new hole for the aft mount. Hopefully your bolts will come > out without issue. > > I hope this helps. I googled marine engine alignment and mostly I don't > like the articles that come up so I can't recommend any of them. They seem > to be talking about something other than what applies to me, and likely to > you as well. This picture may help though. Just use a feeler gauge instead > of the tissue: > http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif > > <http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif>Allen > > > On Tue, Jan 11, 2011 at 6:39 PM, Helen Horn <helenhorn@...> wrote: > > > resending in case you missed how to align the shaft at the coupler, Helen > > > > ----- Forwarded Message ---- > > *From:* Helen Horn <helenhorn@...> > > *To:* Ca… [at] yahoogroups.com > > *Sent:* Sun, January 9, 2011 10:56:55 PM > > *Subject:* vibration/alignment > > > > > > Have you had a diver check your prop or cutlass bearing, you could have a > > damaged prop(bent or even missing a blade or part of one) which could > > vibrate to the point your cutlass gets worn badly, then everything could be > > flopping around and the main receiver of all this would be that coupler. > > Have you hauled your boat and checked the shaft, it could be slightly bent? > > A diver can grab the prop blade and shake it and check for worn out cutlass > > bearing, it should be snug and have no play. Also, your prop may have struck > > something, and perhaps your strut is bent(if you have one). Just some things > > I've observed at boatyards, and even after you haul a boat and do shaft work > > you put the boat in the water and do an alignment 24 hours later after the > > hull has resumed its waterborn shape. There should be no vibrations after > > that, or you do the alignment until you get it right. The coupling between > > the engine and the dampener should be within .002 when you disconnect them. > > (the shaft has to be checked to be sure it is not moving) Then you adjust > > your engine to correct the alignment. It would be good to check this before > > you harm your engine or yourself..... Helen (p.s. one time a commercial > > salmon boat I half-owned had wrapped a piece (long piece) of polypro line > > from some lost crabpot around the shaft between the prop and the bearing and > > it melted on hard and luckily got diagnosed before it pulled that prop shaft > > right out of the boat.) > > > > > > > > >

There is a section in the gray marine manual on aligning an engine. My engine is bolted down to some frames with lag bolts. No rubber anywhere so yes, some engines have truly stiff mounts. I do not know about aligning an engine with rubber mounts but I think it is less critical, not sure. Anyway, you can buy this manual for $26 online or you can get it on my web site for free. If anyone else has a gray marine engine and wants a manual, this web page will be there for you. http://l-36.com/gray_marine.php <http://l-36.com/gray_marine.php>I have not linked it yet so you all are the first to know about it. I just decided to post if free about an hour ago. What it basically says is take the bolts out and make sure you cannot insert a .003 feeler gauge anywhere around the output flange, which is somewhat different than what I posted earlier. I think the picture will help. It is on page 16. The sketchup file is really only useful if you enter the dimensions of your engine and drivetrain but I attached the drawing so you can get the idea. I entered the existing gaps and then essentially added shims in sketchup so I would know what I needed to add on the real engine. Worked great. On Sun, Jan 16, 2011 at 12:38 PM, matthewwenman <mw… [at] gmail.com> wrote: > > > Hi Allen, > > I also use Google Sketchup, would you be willing the share the document you > created with me/us? I think it would be helpful in my trying to understand > what I'm dealing with. > > I called a mechanic this week to just talk through this stuff and see if I > should have someone come look at it or if I can handle the issues my self. > He said something interesting about the large rubber "coupler" (not sure > what to call it). He mentioned that because of it's flexibility the engine > does not need to be aligned as well as an engine with stiff mounts (do any > engines have truly stiff mounts?). I'm having a hard time believing him, and > am thinking that the closer alignment I can get the better. > > Frans mentioned,"The rubber coupler you were referring to is not designed > to dampen engine vibration, it is designed to absorb torsional strain in the > shaft as it rotates." > > What is the benefit of this? Less strain on the transmission? Do most > inboards have this? Is it located in the same part of the shaft (between the > trans fange and the shaft flange)? > > I am looking in to the Auquadrive system. (http://www.aquadrive.net/) Does > anyone have one installed that can give feedback? Worth the investment? Is > it really as effective as they say? (95% less vibration and 50% less > noise).. > > All very helfpul, thanks! > > Matt > > > --- In Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com>, Allen > Edwards <allen.edwards@...> wrote: > > > > I think this is excellent advice. Having just gone through removing a bad > > vibration by aligning the engine I will elaborate on the advice Helen is > > giving. > > > > The test for alignment is between the engine and the shaft. It is > measured > > on the coupling flange at the outer edge of the flange. What I did was > > unbolt the flange and pull it back from the engine a bit. Take a feeler > > gauge, say 0.020 and press the prop shaft back up to the engine with the > > gauge between so you know that there is 0.020 between them. Have the > gauge > > on the top. Then see what gauge fits on the bottom and the sides. They > > should be close to 0.020. Helen says 0.002 so that would mean that a > gauge > > between 0.018 and 0.022 is the same fit as the 0.020 gauge on top. I > think > > I used a guideline of 0.003 but in any case as I started with a > difference > > of 0.014 so I had a problem. To fix the problem I moved the engine up on > > the forward motor mounts and over toward port. Oh, I forgot. Take the > prop > > flange and move it athwardship as well as up and down. The flange should > be > > more or less centered. Mine wasn't so I moved the engine a bit to port. > > Moving the forward end of the engine up moved the flange down and that > > helped in my case. You can calculate how much you have to move the engine > > based on the distance from the motor mounts and the output flange. I drew > > it up on Google Sketchup and used the measurements from that. I removed > the > > old lag bolts that were holding the motor mounts down. Three came out and > > one broke. I had to epoxy some wood to extend where the mount was so that > I > > could drill a new hole for the aft mount. Hopefully your bolts will come > > out without issue. > > > > I hope this helps. I googled marine engine alignment and mostly I don't > > like the articles that come up so I can't recommend any of them. They > seem > > to be talking about something other than what applies to me, and likely > to > > you as well. This picture may help though. Just use a feeler gauge > instead > > of the tissue: > > http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif > > > > <http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif>Allen > > > > > > On Tue, Jan 11, 2011 at 6:39 PM, Helen Horn <helenhorn@...> wrote: > > > > > resending in case you missed how to align the shaft at the coupler, > Helen > > > > > > ----- Forwarded Message ---- > > > *From:* Helen Horn <helenhorn@...> > > > *To:* Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com> > > > *Sent:* Sun, January 9, 2011 10:56:55 PM > > > *Subject:* vibration/alignment > > > > > > > > > Have you had a diver check your prop or cutlass bearing, you could have > a > > > damaged prop(bent or even missing a blade or part of one) which could > > > vibrate to the point your cutlass gets worn badly, then everything > could be > > > flopping around and the main receiver of all this would be that > coupler. > > > Have you hauled your boat and checked the shaft, it could be slightly > bent? > > > A diver can grab the prop blade and shake it and check for worn out > cutlass > > > bearing, it should be snug and have no play. Also, your prop may have > struck > > > something, and perhaps your strut is bent(if you have one). Just some > things > > > I've observed at boatyards, and even after you haul a boat and do shaft > work > > > you put the boat in the water and do an alignment 24 hours later after > the > > > hull has resumed its waterborn shape. There should be no vibrations > after > > > that, or you do the alignment until you get it right. The coupling > between > > > the engine and the dampener should be within .002 when you disconnect > them. > > > (the shaft has to be checked to be sure it is not moving) Then you > adjust > > > your engine to correct the alignment. It would be good to check this > before > > > you harm your engine or yourself..... Helen (p.s. one time a commercial > > > salmon boat I half-owned had wrapped a piece (long piece) of polypro > line > > > from some lost crabpot around the shaft between the prop and the > bearing and > > > it melted on hard and luckily got diagnosed before it pulled that prop > shaft > > > right out of the boat.) > > > > > > > > > > > > > > > > >

Hello Matt, I forgot to mention earlier there's an easy test you can do to see if your engine is misaligned or not. Switch the transmission in and out of gear while keeping an eye on the coupler. If the coupler wobbles in a egg shaped fashion at all when you switch gears this is a good indicator that you're out of alignment. This may be a little difficult in your case since its a Farymann and everything seems to vibrate while she's running but its worth a try. Its a quick and easy test you can do yourself. Make sure all your mounts are in good shape too, my Farymann would shake wildly when the rubber mounts were torn. I changed 3 out of 4 of them in 5 years time running with the Farymann. Hope this helps, good luck. Frans From: matthewwenman <mw… [at] gmail.com> To: Ca… [at] yahoogroups.com Sent: Sun, January 16, 2011 12:38:23 PM Subject: [Cal_Boats] Re: Fw: vibration/alignment Hi Allen, I also use Google Sketchup, would you be willing the share the document you created with me/us? I think it would be helpful in my trying to understand what I'm dealing with. I called a mechanic this week to just talk through this stuff and see if I should have someone come look at it or if I can handle the issues my self. He said something interesting about the large rubber "coupler" (not sure what to call it). He mentioned that because of it's flexibility the engine does not need to be aligned as well as an engine with stiff mounts (do any engines have truly stiff mounts?). I'm having a hard time believing him, and am thinking that the closer alignment I can get the better. Frans mentioned,"The rubber coupler you were referring to is not designed to dampen engine vibration, it is designed to absorb torsional strain in the shaft as it rotates." What is the benefit of this? Less strain on the transmission? Do most inboards have this? Is it located in the same part of the shaft (between the trans fange and the shaft flange)? I am looking in to the Auquadrive system. (http://www.aquadrive.net/) Does anyone have one installed that can give feedback? Worth the investment? Is it really as effective as they say? (95% less vibration and 50% less noise).. All very helfpul, thanks! Matt --- In Ca… [at] yahoogroups.com, Allen Edwards <allen.edwards@...> wrote: > > I think this is excellent advice. Having just gone through removing a bad > vibration by aligning the engine I will elaborate on the advice Helen is > giving. > > The test for alignment is between the engine and the shaft. It is measured > on the coupling flange at the outer edge of the flange. What I did was > unbolt the flange and pull it back from the engine a bit. Take a feeler > gauge, say 0.020 and press the prop shaft back up to the engine with the > gauge between so you know that there is 0.020 between them. Have the gauge > on the top. Then see what gauge fits on the bottom and the sides. They > should be close to 0.020. Helen says 0.002 so that would mean that a gauge > between 0.018 and 0.022 is the same fit as the 0.020 gauge on top. I think > I used a guideline of 0.003 but in any case as I started with a difference > of 0.014 so I had a problem. To fix the problem I moved the engine up on > the forward motor mounts and over toward port. Oh, I forgot. Take the prop > flange and move it athwardship as well as up and down. The flange should be > more or less centered. Mine wasn't so I moved the engine a bit to port. > Moving the forward end of the engine up moved the flange down and that > helped in my case. You can calculate how much you have to move the engine > based on the distance from the motor mounts and the output flange. I drew > it up on Google Sketchup and used the measurements from that. I removed the > old lag bolts that were holding the motor mounts down. Three came out and > one broke. I had to epoxy some wood to extend where the mount was so that I > could drill a new hole for the aft mount. Hopefully your bolts will come > out without issue. > > I hope this helps. I googled marine engine alignment and mostly I don't > like the articles that come up so I can't recommend any of them. They seem > to be talking about something other than what applies to me, and likely to > you as well. This picture may help though. Just use a feeler gauge instead > of the tissue: > http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif > > <http://www.marinemechanic.com/nrfpt_dir/engine_flange.gif>Allen > > > On Tue, Jan 11, 2011 at 6:39 PM, Helen Horn <helenhorn@...> wrote: > > > resending in case you missed how to align the shaft at the coupler, Helen > > > > ----- Forwarded Message ---- > > *From:* Helen Horn <helenhorn@...> > > *To:* Ca… [at] yahoogroups.com > > *Sent:* Sun, January 9, 2011 10:56:55 PM > > *Subject:* vibration/alignment > > > > > > Have you had a diver check your prop or cutlass bearing, you could have a > > damaged prop(bent or even missing a blade or part of one) which could > > vibrate to the point your cutlass gets worn badly, then everything could be > > flopping around and the main receiver of all this would be that coupler. > > Have you hauled your boat and checked the shaft, it could be slightly bent? > > A diver can grab the prop blade and shake it and check for worn out cutlass > > bearing, it should be snug and have no play. Also, your prop may have struck > > something, and perhaps your strut is bent(if you have one). Just some things > > I've observed at boatyards, and even after you haul a boat and do shaft work > > you put the boat in the water and do an alignment 24 hours later after the > > hull has resumed its waterborn shape. There should be no vibrations after > > that, or you do the alignment until you get it right. The coupling between > > the engine and the dampener should be within .002 when you disconnect them. > > (the shaft has to be checked to be sure it is not moving) Then you adjust > > your engine to correct the alignment. It would be good to check this before > > you harm your engine or yourself..... Helen (p.s. one time a commercial > > salmon boat I half-owned had wrapped a piece (long piece) of polypro line > > from some lost crabpot around the shaft between the prop and the bearing and > > it melted on hard and luckily got diagnosed before it pulled that prop shaft > > right out of the boat.) > > > > > > > > >