A number of months ago I posted a question about maintenance on the Volvo Penta shaft seal on my Beneteau 361. I've learned to add grease and burp the seal and I've learned to live with a few ounces of water after running the engine for 4-8 hours. I can live with a bit of water in the indentation under the shaft. Here's my question. Since water collecting in the engine compartment doesn't empty into the bilge system for environmental reason, how do I get it out other than by hand with a sponge. The way it is now, I have to sponge out the bit of water each night or at some point it becomes a lot of water. Can I drill a small 'weep' hole to get the water to drain into the bilge? Other than this one very annoying shaft seal, I truly love my B361.
Shaft Seal
- Thread starter Stan21606
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I have the same problem with my boat, If you don't get rid of the water every day it starts to stew in the heat and the first thing you know it realy smells funky in the cabin, especialy if can't make it to the boat for a week or so. I realy wouldn't want to start drilling through stuff to drain into the bilge so last year I bought a small wet dry shop vac that I keep in the boat and every now and the I suck up the water with it and dump it over the side. This spring I am installing a bilge pump with a no return valve next to the pump to get the water out of there and I plan to run the hose out and connect it to the sink drain , I will also install a shut off valve at the junction, that I will open when the bilge pump has to be used and then can be shut off so no sea water or sink water can back wash into it. Let me know what you think ?
I would change the seal
Stan, I think your seal has seen better days. It is time to change it for a new one. My boat is already 4 years old I am already planning to do that with mine this spring and I am only getting a small amount of water that stays near the seal and comes out with sponge out once every week. I you are getting that much water, you need to be aware that you could be in danger of a catastrophic failure of the seal, something you don't want to deal with. Changing the seal is easy and should not cost too much, I will post the price soon since I am ordering it now.
Stan, I think your seal has seen better days. It is time to change it for a new one. My boat is already 4 years old I am already planning to do that with mine this spring and I am only getting a small amount of water that stays near the seal and comes out with sponge out once every week. I you are getting that much water, you need to be aware that you could be in danger of a catastrophic failure of the seal, something you don't want to deal with. Changing the seal is easy and should not cost too much, I will post the price soon since I am ordering it now.
Another 361
On the Sailnet forum I found a Beneteau 361 that had the identical problem. It turns out that he a minute crack where the stern tube went into his hull. The problem only showed up when the hull flexed from vibration or heavy seas. The water came in under the fuel tank and dripped down into the indentation under the shaft seal. He hauled the boat, caulked with 5200 and has been dry for 6 months. I've got a diver going down to take a look and run a bead of 5200 to see if it makes a difference. If it does I'll haul the boat for a more permanent repair.
On the Sailnet forum I found a Beneteau 361 that had the identical problem. It turns out that he a minute crack where the stern tube went into his hull. The problem only showed up when the hull flexed from vibration or heavy seas. The water came in under the fuel tank and dripped down into the indentation under the shaft seal. He hauled the boat, caulked with 5200 and has been dry for 6 months. I've got a diver going down to take a look and run a bead of 5200 to see if it makes a difference. If it does I'll haul the boat for a more permanent repair.
Stan, I just ordered the seal
from Beneteau USA. They have a great new web site to find part numbers and order directly from them. Although the pages for the 361 are still under construction, you can do the shopping using the pages for the 331 that share most of the standard parts with the 361. After some work and calls, I found out the trick of not entering hull numbers when you want to obtain part numbers from standard items (not on red). The part in question is called SEAL PROP SHAFT VOLVO D25 Part number 718940 and costs $67.95, not cheap but worth if you want to sleep well at night. The little red gadget that you can see around the hose leading to the shaft seal is used to push grease between the seal and the shaft periodically. Good luck
from Beneteau USA. They have a great new web site to find part numbers and order directly from them. Although the pages for the 361 are still under construction, you can do the shopping using the pages for the 331 that share most of the standard parts with the 361. After some work and calls, I found out the trick of not entering hull numbers when you want to obtain part numbers from standard items (not on red). The part in question is called SEAL PROP SHAFT VOLVO D25 Part number 718940 and costs $67.95, not cheap but worth if you want to sleep well at night. The little red gadget that you can see around the hose leading to the shaft seal is used to push grease between the seal and the shaft periodically. Good luck
Do it better
Spend some extra $$ and install a PSS Dripless seal. The volvo seal scares me, there isn't a whole lot between seawater (or lakewater) and the bilge, just two very flimsy lip seals! Wiggle the seal just a little and watch water seep in, so imagine how much it wiggles with the propshaft turning. And, if the shaft isn't aligned centrally to the sterntube, you will never get a perfect seal. My PSS doesn't drip a single drop! Tim
Spend some extra $$ and install a PSS Dripless seal. The volvo seal scares me, there isn't a whole lot between seawater (or lakewater) and the bilge, just two very flimsy lip seals! Wiggle the seal just a little and watch water seep in, so imagine how much it wiggles with the propshaft turning. And, if the shaft isn't aligned centrally to the sterntube, you will never get a perfect seal. My PSS doesn't drip a single drop! Tim
I am not that sure Tim
You may be scared about the two flimsy lip seals. My experience is that there is no leak in the water lubricated Volvo seals until they begin to wear out. Yes, you need to make sure the lip seals are lubricated and if you do not install them properly they may leak. You also may need to replace them every 4 years as you replace your raw water impeller every year. The good thing is that a small progressive leak tells you it is time to change the seal well in advance of any kind of catastrophic failure. Now, for 3x the price you may feel safer with the Dripless seal and you should expect at least 12 years of use to make it cost effective. However, think about the possibility of the seal seizing while the engine off. Next time you turn on your engine, the whole rubber bellows could be shredded to pieces and you will have little time to identify the source of a very large water leak. May this ever happen? Most likely not, but some times parts that appear flimsy and fail slowly may be more reassuring than those strong that could fail in a catastrophic way.
You may be scared about the two flimsy lip seals. My experience is that there is no leak in the water lubricated Volvo seals until they begin to wear out. Yes, you need to make sure the lip seals are lubricated and if you do not install them properly they may leak. You also may need to replace them every 4 years as you replace your raw water impeller every year. The good thing is that a small progressive leak tells you it is time to change the seal well in advance of any kind of catastrophic failure. Now, for 3x the price you may feel safer with the Dripless seal and you should expect at least 12 years of use to make it cost effective. However, think about the possibility of the seal seizing while the engine off. Next time you turn on your engine, the whole rubber bellows could be shredded to pieces and you will have little time to identify the source of a very large water leak. May this ever happen? Most likely not, but some times parts that appear flimsy and fail slowly may be more reassuring than those strong that could fail in a catastrophic way.
Valid point...
Jose, You bring up a valid point about the cost difference. I'm not sure the slip ring (stainless) could possibly sieze up on the carbon seal, though. I do know I never worry about maintaining it, other than an occasional look-see. I used to have an old F32 that I got from my dad and he had put a dripless seal on it back in the late 80's, and I didn't replace it until I got the boat in 2001. It was actually the bellows that was cracking from age, while the plastic seal was fine. This was not a PSS unit, but similar in design. The new PSS units use better technology in the seal (I think its carbon as opposed to plastic). The boat was used extensively in the 80's and early 90's, but sat after that for a number of years with very little use until I got it. I have a friend who has a 2000 321 with very little use on it (50 hours on the engine), and his Volvo seal was leaking. He decided to go with the PSS seal after seeing mine, and we will install it this Spring. When I helped him remove the Volvo seal last Fall, we found the engine was in poor alignment with the sterntube (from the factory as he never touched it), which no doubt contributed to the failure of the Volvo seal. Along those lines, when I replaced my seal I found the engine was not in proper alignment with the propshaft either (1999 321). Not only was the shaft not centered in the sterntube, the aft end of the engine was "cocked" upward in relation to the shaft so that when you mated the shaft flange to the gearbox flange, the bottom of the flanges were together while the top had a gap. When the bolts are tightened, the flanges will mate because the engine mounts flex to accomodate this. However, this effectively changes the tuning of the mounts as they become "pre-loaded". My engine used to seem to cause a lot of vibration (like an unbalanced prop) until I fixed this problem by simply adjusting the engine mounts so the flanges met perfectly against eachother before tightening the bolts. I'd be willing to bet a lot of folks out there wonder why they have a lot of vibration while motoring, and assume the prop is unbalanced, or just assume that's the nature of the 3GMF30. Anyway, the seal thing is certainly a personal preference, and installed and maintained properly the Volvo seal should do a good job. Cheers! Tim
Jose, You bring up a valid point about the cost difference. I'm not sure the slip ring (stainless) could possibly sieze up on the carbon seal, though. I do know I never worry about maintaining it, other than an occasional look-see. I used to have an old F32 that I got from my dad and he had put a dripless seal on it back in the late 80's, and I didn't replace it until I got the boat in 2001. It was actually the bellows that was cracking from age, while the plastic seal was fine. This was not a PSS unit, but similar in design. The new PSS units use better technology in the seal (I think its carbon as opposed to plastic). The boat was used extensively in the 80's and early 90's, but sat after that for a number of years with very little use until I got it. I have a friend who has a 2000 321 with very little use on it (50 hours on the engine), and his Volvo seal was leaking. He decided to go with the PSS seal after seeing mine, and we will install it this Spring. When I helped him remove the Volvo seal last Fall, we found the engine was in poor alignment with the sterntube (from the factory as he never touched it), which no doubt contributed to the failure of the Volvo seal. Along those lines, when I replaced my seal I found the engine was not in proper alignment with the propshaft either (1999 321). Not only was the shaft not centered in the sterntube, the aft end of the engine was "cocked" upward in relation to the shaft so that when you mated the shaft flange to the gearbox flange, the bottom of the flanges were together while the top had a gap. When the bolts are tightened, the flanges will mate because the engine mounts flex to accomodate this. However, this effectively changes the tuning of the mounts as they become "pre-loaded". My engine used to seem to cause a lot of vibration (like an unbalanced prop) until I fixed this problem by simply adjusting the engine mounts so the flanges met perfectly against eachother before tightening the bolts. I'd be willing to bet a lot of folks out there wonder why they have a lot of vibration while motoring, and assume the prop is unbalanced, or just assume that's the nature of the 3GMF30. Anyway, the seal thing is certainly a personal preference, and installed and maintained properly the Volvo seal should do a good job. Cheers! Tim
Shaft Log
I appreciate the input. I'm convinced that my problem is in the stern tube where the log exits the hull. This is the picture of the 361 that had the same problem as R Time. I have a diver going down today to take a look and run a bead of 5200 around the tube. I'll let you knwo the outcome.
I appreciate the input. I'm convinced that my problem is in the stern tube where the log exits the hull. This is the picture of the 361 that had the same problem as R Time. I have a diver going down today to take a look and run a bead of 5200 around the tube. I'll let you knwo the outcome.
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