All, I have a Yanmar 3GMF engine that has a water pump with a mind of its own. Several weeks ago my wife took the boat out with some girlfriends and heard that heart-sinking hollow sound coming from the exhaust.......no water coming out!!! She beat it back to the slip she'd just left and in the process, the impeller was destroyed. I bought a replacement impeller (actually three of them) and installed it. The upper hose to the heat exchanger was of course dry so I filled it and stuck it back on. The next day she tried again with her friends and no water again. I rechecked the impeller and refilled the hose and all was fine. We motored around the marina for 45 minutes or so and returned to the slip. Fast forward two weeks and yesterday she along with the same gals went for another glorious sail with no engine cooling problems at all until hours later as she was dropping the main prior to returning to our slip. The engine fired right up but no water, AGAIN!!! To her credit, she sailed our boat back into the slip and all returned to land safe and sound. As a start, I'm tempted to replace all the hoses especially and including the factory formed one from the pump to the heat exchanger but including the one from the seacock to the strainer and from there to the pump. Has anyone had a similar experience and can anyone shed light on how to solve this perplexing problem? It sure has me scratching my head. Thanks in advance, Glyn Judson, E31 hull #55, Marina del Rey CA
Exhaust water blues.
- Thread starter Glyn Judson
- Start date
Glyn, I know a sailor of your caliber has already checked the strainer basket, but the only three things that come to mind are, a gasket on the strainer sucking air, the collapse of the hose before or aft of the strainer causing said impeller to commit suicide due to lack of water, or the cam in the water pump worn as such that it eats the impeller.
Not much, but that seems to be the typical causes of these problems.
The strainer gasket. Troublesome apparatuses..
And here of late, when tearing down a Detroit raw water pump, the cam felt good just running my finger in the cavity, but upon pulling it out for a thorough inspection, it was then deemed to be replaced. It was worn in places that I couldn't detect with the finger test.
Not much, but that seems to be the typical causes of these problems.
The strainer gasket. Troublesome apparatuses..
And here of late, when tearing down a Detroit raw water pump, the cam felt good just running my finger in the cavity, but upon pulling it out for a thorough inspection, it was then deemed to be replaced. It was worn in places that I couldn't detect with the finger test.
Critters in the intake.
Edd, Thanks, I'll ask my dive service to run a coat hanger up the raw water intake but in these SoCal waters, it's highly unlikely that it's blocked. Thanks to others on the list for making suggestions, I plan to recheck the threaded cover on my Groco strainer, run the engine (raw water pump) with the hose detached from the heat exchanger to ascertain proper water flow, rod out the tubes in the heat exchanger and finally replace all the related hoses. The puzzler is that I motored around the marina for 30 to 45 minutes two weeks ago with no problem at all. Then Marilyn used the engine two days ago for approximately 30 minutes to get out of the marina for a four hour sail and only then did the water cease to flow into the exhaust when she attempted to motor back into the slip. I have a relatively new exhaust elbow, having replaced it 12 to 18 months ago so I feel I can rule that out, not that I can see that it would contribute to the problem anyhow. Someone suggested that it might be a collapsed raw water intake hose which might be a possibility. I had that happen several years ago with the fresh water tank fill hose, replacement being the only remedy. This is a real head scratcher, I'll tell you that. Thanks to all of you for the great suggestions and please offer more as they occur to you. Cheers, Glyn Judson, E31 hull #55, (Yanmar 3GMF) Marina del Rey CA
Edd, Thanks, I'll ask my dive service to run a coat hanger up the raw water intake but in these SoCal waters, it's highly unlikely that it's blocked. Thanks to others on the list for making suggestions, I plan to recheck the threaded cover on my Groco strainer, run the engine (raw water pump) with the hose detached from the heat exchanger to ascertain proper water flow, rod out the tubes in the heat exchanger and finally replace all the related hoses. The puzzler is that I motored around the marina for 30 to 45 minutes two weeks ago with no problem at all. Then Marilyn used the engine two days ago for approximately 30 minutes to get out of the marina for a four hour sail and only then did the water cease to flow into the exhaust when she attempted to motor back into the slip. I have a relatively new exhaust elbow, having replaced it 12 to 18 months ago so I feel I can rule that out, not that I can see that it would contribute to the problem anyhow. Someone suggested that it might be a collapsed raw water intake hose which might be a possibility. I had that happen several years ago with the fresh water tank fill hose, replacement being the only remedy. This is a real head scratcher, I'll tell you that. Thanks to all of you for the great suggestions and please offer more as they occur to you. Cheers, Glyn Judson, E31 hull #55, (Yanmar 3GMF) Marina del Rey CA
Let's see.... either it pumps fine or when started up, no water gets to the impeller in time to flow thru it before the rubber impeller is burned up.
Sounds like the water is not present - sometimes - at the water pump intake after the boat sits.
I know that those little pumps, at least the Oberdorfer brand on my Universal, can struggle to suck up water when their little chamber is empty. Like after I change out the impeller. or clean the strainer. I grease the new impeller and after a few seconds of running it draws in water and all is well.
I have replaced that whole pump ($) once over the years just because it had lost some suction from emplargement of the inside chamber. While that was due to the mocroscopic (and sharp) volcanic fine silt in suspension in the Columbia River, I could imagine most any such pump presenting some internal surface erosion from all the water passing thru it, after enough decades and hours of use. We do have kind of a special situation here, and often a raw water pump will need replacing at about 2K hours, give or take.
OTOH, if the water at the entry/intake of the pump housing is there sometimes and not there some other times, that's certainly an "upstream " mystery. Piece by piece, there's an intake valve, hose to the strainer, strainer, and hose to pump. Is there a possible air leak in the pump itself? Cover and gasket? shaft?
Solution has gotta be right there, and for some reason it's invisible!
Wish I could be more helpful.
Good luck,
Loren
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Tom Metzger
Sustaining Partner
Glyn - I'm late to the conversation, but it sounds to me like a leak on the gozinta side of your pump. When you heel over the pump/hoses/filter drain and can't re-prime. Old hose/kink? Bad gasket in the filter/cracked bowl/loose plug?
When you have a failure is there water in the strainer?
Rather than hiring a diver I would pull off the inlet hose with the seacock closed, open it and you should get an indication if the inlet is clear. I would then go back hose by hose to see if I could easily suck water up from the thru hull . You should also be able to blow from the pump's gozouta side hose to see if there is a blockage on that side.
I recently had a similar problem with the fuel system. I used the same approach I described to you to prove that the new electric pump wasn't working and to find a line blockage. I used a Jabsco brass hand pump to suck the diesel rather than my mouth. Is Marina Del Ray water as toxic as diesel?
I had a friend a few years ago with the same engine and the same problem. He wasn't much of a sailor nor a mechanic and got so frustrated that he sold the boat and bought a fifth wheel camper. His wife was one unhappy lady. Not my recommended approach.
When you have a failure is there water in the strainer?
Rather than hiring a diver I would pull off the inlet hose with the seacock closed, open it and you should get an indication if the inlet is clear. I would then go back hose by hose to see if I could easily suck water up from the thru hull . You should also be able to blow from the pump's gozouta side hose to see if there is a blockage on that side.
I recently had a similar problem with the fuel system. I used the same approach I described to you to prove that the new electric pump wasn't working and to find a line blockage. I used a Jabsco brass hand pump to suck the diesel rather than my mouth. Is Marina Del Ray water as toxic as diesel?
I had a friend a few years ago with the same engine and the same problem. He wasn't much of a sailor nor a mechanic and got so frustrated that he sold the boat and bought a fifth wheel camper. His wife was one unhappy lady. Not my recommended approach.
Water flow blues.
All, First of all, I need to thank each and every one of you for your thoughtful input. The collective wisdom of you all has given me a game plan of detecting, remedying and solving this problem. I'll start at the source, the seacock and work my way up stream, past the strainer, past the 3-way valve I use for fresh water flushing the engine after each use, from there to the pump and then past that to the heat exchanger. Along the way, I'll recheck the impeller, run the engine withthe top hose disconnected to determine water flow, take the end cap off the heat exchanger and rod it out. As a matter of form, I plan to replace every piece of hose as I go and that darned thing better pump after that. My money is one of the lengths of hose having developed an inner blister that unpredictably flaps across the ID, thereby staunching flow. Cheers, Glyn Judson, E31 hull #55, Marina del REy where the water is slightly cleaner than diesel.
All, First of all, I need to thank each and every one of you for your thoughtful input. The collective wisdom of you all has given me a game plan of detecting, remedying and solving this problem. I'll start at the source, the seacock and work my way up stream, past the strainer, past the 3-way valve I use for fresh water flushing the engine after each use, from there to the pump and then past that to the heat exchanger. Along the way, I'll recheck the impeller, run the engine withthe top hose disconnected to determine water flow, take the end cap off the heat exchanger and rod it out. As a matter of form, I plan to replace every piece of hose as I go and that darned thing better pump after that. My money is one of the lengths of hose having developed an inner blister that unpredictably flaps across the ID, thereby staunching flow. Cheers, Glyn Judson, E31 hull #55, Marina del REy where the water is slightly cleaner than diesel.
Wait did you say three way valve?
The three way flushing valve could be letting air into the system, it is always easier to pump air than water. Are you sure it is sealing well?
First think I would do it really make sure that no AIR can be sucked into that valve.
Guy
The three way flushing valve could be letting air into the system, it is always easier to pump air than water. Are you sure it is sealing well?
First think I would do it really make sure that no AIR can be sucked into that valve.
Guy
3-way valve.
Guy, Thanks for the thought, I'll certainly consider that but if it is the problem area, I'll be very surprised. That valve has been a part of my fresh water management system manifold for more years than I can remember, maybe 15 years if I had to guess. It has never failed to date but there is always a first time for everything. I'll be sure to include it in my inspection. The way it works, there is always water in the valve. It normally directs sea water to the raw water pump until I turn the handle which redirects it to pull from my onboard main fresh water tank. When flushing of the heat exchanger and water exhaust system is complete (30 seconds at idle and three quarts of water), I kill the engine and re-manifold back to sea water. Glyn, E31 hull #55, Marina del Rey CA
Guy, Thanks for the thought, I'll certainly consider that but if it is the problem area, I'll be very surprised. That valve has been a part of my fresh water management system manifold for more years than I can remember, maybe 15 years if I had to guess. It has never failed to date but there is always a first time for everything. I'll be sure to include it in my inspection. The way it works, there is always water in the valve. It normally directs sea water to the raw water pump until I turn the handle which redirects it to pull from my onboard main fresh water tank. When flushing of the heat exchanger and water exhaust system is complete (30 seconds at idle and three quarts of water), I kill the engine and re-manifold back to sea water. Glyn, E31 hull #55, Marina del Rey CA
Tom Metzger
Sustaining Partner
Yup... That reminds me of my dear old sister... She never had a sick day in her life; than: Bang!!!! :0
Just like that, she was pregnant.
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Hi Glyn, I had a similar issue , found there was a bronze flapper valve to prevent backflow between the exhaust elbow and the waterlift muffler. The pivot pin wore out, allowing the flapper to run around loose in the housing. Occasionally, it would block off the exhaust/water. Was a 3254 Universal. Let us know what you find.
Harold
Harold
Sven
Seglare
I forgot all about this thread ...
When we were out on the water we overheard a VHF discussion that might be relevant.
One of the vessels in the discussion reported how his impellers burned out in the water pump and when he had replaced two he happened to look at the belt idler/tensioning pulley. Turned out that the pulley had seized up and somehow that caused the impeller to burn up.
He didn't say (or we didn't hear) how the pulley caused the impeller problems but I assume that the tension on the belt due to the seized pulley might have pulled the pump to the side too hard.
Of course, you might not even have a pulley but the exchange did make me think about your problem.
-Sven
When we were out on the water we overheard a VHF discussion that might be relevant.
One of the vessels in the discussion reported how his impellers burned out in the water pump and when he had replaced two he happened to look at the belt idler/tensioning pulley. Turned out that the pulley had seized up and somehow that caused the impeller to burn up.
He didn't say (or we didn't hear) how the pulley caused the impeller problems but I assume that the tension on the belt due to the seized pulley might have pulled the pump to the side too hard.
Of course, you might not even have a pulley but the exchange did make me think about your problem.
-Sven
Stupid is as stupid does.
All, I think I got that quote right as taken from Forrest Gump because it sure applies to me. It turns out that the culprit all the time was a loose belt, that little one that drives the raw water pump. It wasn't loose enough to slip all the time and then it would pump sea water just fine. So here's how it all went down and what defines my stupidity based upon assumption. Marilyn ran the onboard, 40 gallon fresh water tank dry, having forgotten to re-manifold the 3-way valve back to sea water the previous time she had taken the boat out and after flushing the heat exchanger. So I open the pump up and find that chopped impeller is all that's left. I installed a new one and had Marilyn start 'er up while I watched the engine, specifically the raw water pump pulley, it's turning just fine. I look up to her and she indicates water coming out of the exhaust, problem solved, I button up the engine cover and we take a 45 minute harbor putt to make sure nothing goes wrong and it doesn't, so we return to the slip. Fast forward to the next time she fires up the engine with all her girl friends aboard and, you guessed it, no water emerging from the exhaust. By now I'm about to tear my hair out and at which point I asked for help from all of you. Here's what I think was happening. The new impeller offered more resistance to turning the pulley than the old one did that got shredded. But that resistance only occurred when one blade of the new impeller was in just the right position to offer just enough resistance upon start up to prevent the pulley from turning. At other times with the blade not offering as much resistance, it would turn the pulley perfectly well. Every time I looked at the engine running, the pulley was turning, but that was just the luck of the draw. I thought I had covered the probability of a loose belt by tightening the pump bracket as far as it was designed to swing. The belt felt a bit loose but not all that loose (or so I convinced myself). Anyhow, I got a new belt, actually two so I now have a spare onboard and the difference in size between the new one and the old was immediately apparent. With the new belt in place, all is well with the world again and the knucklehead mystery is solved. Thanks for all the input, I'm just sorry that I didn't supply you with all the details and I know if I had, you would have zeroed in on the problem immediately. Glyn (slightly smarter now) Judson, E31 hull #55, Marina del Rey, CA
All, I think I got that quote right as taken from Forrest Gump because it sure applies to me. It turns out that the culprit all the time was a loose belt, that little one that drives the raw water pump. It wasn't loose enough to slip all the time and then it would pump sea water just fine. So here's how it all went down and what defines my stupidity based upon assumption. Marilyn ran the onboard, 40 gallon fresh water tank dry, having forgotten to re-manifold the 3-way valve back to sea water the previous time she had taken the boat out and after flushing the heat exchanger. So I open the pump up and find that chopped impeller is all that's left. I installed a new one and had Marilyn start 'er up while I watched the engine, specifically the raw water pump pulley, it's turning just fine. I look up to her and she indicates water coming out of the exhaust, problem solved, I button up the engine cover and we take a 45 minute harbor putt to make sure nothing goes wrong and it doesn't, so we return to the slip. Fast forward to the next time she fires up the engine with all her girl friends aboard and, you guessed it, no water emerging from the exhaust. By now I'm about to tear my hair out and at which point I asked for help from all of you. Here's what I think was happening. The new impeller offered more resistance to turning the pulley than the old one did that got shredded. But that resistance only occurred when one blade of the new impeller was in just the right position to offer just enough resistance upon start up to prevent the pulley from turning. At other times with the blade not offering as much resistance, it would turn the pulley perfectly well. Every time I looked at the engine running, the pulley was turning, but that was just the luck of the draw. I thought I had covered the probability of a loose belt by tightening the pump bracket as far as it was designed to swing. The belt felt a bit loose but not all that loose (or so I convinced myself). Anyhow, I got a new belt, actually two so I now have a spare onboard and the difference in size between the new one and the old was immediately apparent. With the new belt in place, all is well with the world again and the knucklehead mystery is solved. Thanks for all the input, I'm just sorry that I didn't supply you with all the details and I know if I had, you would have zeroed in on the problem immediately. Glyn (slightly smarter now) Judson, E31 hull #55, Marina del Rey, CA
Mort Fligelman
Member III
Just an afterthought
Glynn:
April of 2010 among many things I had the mechanic working on my engine replace the raw water pump with a brand new one......was going from salt to fresh water, and figured that with the heat exchanger boiled out I now had a non salt water system......in the process of installing the new pump it required removing the old 90 degree fittings for the hose connections, and low and behold in one of them was an old impeller blade......
The mechanic said I was just lucky that it jammed in the right position or it could have completely blocked the system.......I had replaced the impeller for safety reasons when I bought the boat in 2006, and the old impeller was intact.....have no idea how long it was in there that way.
If you have the 90 degree fittings have you checked them for remnants of the shredded impeller??????? just an afterthought
Regards
Glynn:
April of 2010 among many things I had the mechanic working on my engine replace the raw water pump with a brand new one......was going from salt to fresh water, and figured that with the heat exchanger boiled out I now had a non salt water system......in the process of installing the new pump it required removing the old 90 degree fittings for the hose connections, and low and behold in one of them was an old impeller blade......
The mechanic said I was just lucky that it jammed in the right position or it could have completely blocked the system.......I had replaced the impeller for safety reasons when I bought the boat in 2006, and the old impeller was intact.....have no idea how long it was in there that way.
If you have the 90 degree fittings have you checked them for remnants of the shredded impeller??????? just an afterthought
Regards
Blocked elbows.
Moret, Thanks for the tip, I did however check for blockage there and the elbow was clear. Glyn
Moret, Thanks for the tip, I did however check for blockage there and the elbow was clear. Glyn