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#1
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![]() The problem with the 15 hp is as follows. I bought this motor two years ago from a guy who claimed to be selling it for the wife of a deceased friend. He didn't have much info on the engine except to say it had not been run in at least 5 years. (I willing to bet it was like 10 or more years.) Although originally I could not get it started, I've now had it serviced by three different repair shops, all with OMC backgrounds. It's been decarbonized, had the carburetor cleaned and rebuilt, new plugs and had numerous other minor issues resolved. The water pump hasn't been overhauled, but the mechanics have all claimed that the impeller is fine as the engine produces a sufficient "pee-stream." However, the big problem hasn't been solved. If its been sitting for that long I would replace the impeller ASAP. When the engine hasn't been used overnight or for a few days, it starts on the first or second pull and will idle OK. It will also run fine under full power on that first run and push our 14ft aluminum skiff at 20-25 miles an hour. From that point the reliability goes downstream fast and has me ready to use it as an anchor. The fun starts when the engine will not idle after being run at full or half throttle. It will also not restart easily if it is hot and/or has stalled out. You can sometimes get it started if you override the neutral-start interlock and immediately give more throttle than the "over-rev" limiter in neutral will allow. I know it's dangerous and for that reason won't let my kids drive it. Letting it sit for a while, an hour or so, gives you a better shot of restarting it, but not reliably and/or keeping it running. Ironically, when I've picked it up, all the shops have told me how great it runs in the test tank; they claim it starts right up, idles nicely and runs as well as can be expected for this age motor. I don't doubt that it does (in their test tanks), but I think they're all missing something. On the other hand, I'm sure they think I'm neurotic about this engine. Any thoughts suggestions or insights would be greatly appreciated. Bill Lav Have you checked the fuel system for adequate venting? If not vented properly a vacuum can develop in the tank causing the problem you describe. Next time it happens try removing the gas cap and check for a vacuum. |
#2
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On Tue, 12 Aug 2003 02:27:34 GMT, "Bill Lavernoich"
wrote: The problem with the 15 hp is as follows. I bought this motor two years ago from a guy who claimed to be selling it for the wife of a deceased friend. He didn't have much info on the engine except to say it had not been run in at least 5 years. (I willing to bet it was like 10 or more years.) Although originally I could not get it started, I've now had it serviced by three different repair shops, all with OMC backgrounds. It's been decarbonized, had the carburetor cleaned and rebuilt, new plugs and had numerous other minor issues resolved. The water pump hasn't been overhauled, but the mechanics have all claimed that the impeller is fine as the engine produces a sufficient "pee-stream." However, the big problem hasn't been solved. When the engine hasn't been used overnight or for a few days, it starts on the first or second pull and will idle OK. It will also run fine under full power on that first run and push our 14ft aluminum skiff at 20-25 miles an hour. From that point the reliability goes downstream fast and has me ready to use it as an anchor. The fun starts when the engine will not idle after being run at full or half throttle. It will also not restart easily if it is hot and/or has stalled out. You can sometimes get it started if you override the neutral-start interlock and immediately give more throttle than the "over-rev" limiter in neutral will allow. I know it's dangerous and for that reason won't let my kids drive it. Letting it sit for a while, an hour or so, gives you a better shot of restarting it, but not reliably and/or keeping it running. Ironically, when I've picked it up, all the shops have told me how great it runs in the test tank; they claim it starts right up, idles nicely and runs as well as can be expected for this age motor. I don't doubt that it does (in their test tanks), but I think they're all missing something. On the other hand, I'm sure they think I'm neurotic about this engine. Any thoughts suggestions or insights would be greatly appreciated. Bill Lav Bill- I suspect that the engine shops haven't run this engine long enough to heat it up. Time is money, ya' know? ![]() Your problems sound like they are heat related, which could be a coil breaking down, condenser breaking down, etc. Call the last guy that worked on it and ask if he guarantees his work. If not, move on, and find a shop that will do it right. FWIW, get the impellor replaced. If the old one is brittle and cracked, it could "pee" at idle, and fail to move enough water at WOT. It's also possible that there's a partial blockage in the water flow. Finding a good boat mechanic is a lot like finding a good car mechanic. You pays your dollar, and you takes your chances. I've been 50% lucky, I've got a great boat mechanic. Good luck, noah Courtesy of Lee Yeaton, See the boats of rec.boats www.TheBayGuide.com/rec.boats |
#3
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I'm leaning on a bad stator on this one. When they get hot, the
windings expand and if something's broken loose the spark sucks until it gets cool again. When it's cool and running fine, hook one plug wire up to an external spark plug that's grounded to the block so you can see the spark. Note how the spark looks. Then, when it's running like crap, do that again and see if you don't see a real thin, wimpy weak spark that compression can blow out the fire to..... I had a stator on an Evinrude 3-cyl 55 that worked great whenever a mechanic was looking at it because, in his haste, he never got the motor hot enough to make it fail.... Gets hot under that flywheel..... On Tue, 12 Aug 2003 02:27:34 GMT, "Bill Lavernoich" wrote: The problem with the 15 hp is as follows. I bought this motor two years ago from a guy who claimed to be selling it for the wife of a deceased friend. He didn't have much info on the engine except to say it had not been run in at least 5 years. (I willing to bet it was like 10 or more years.) Although originally I could not get it started, I've now had it serviced by three different repair shops, all with OMC backgrounds. It's been decarbonized, had the carburetor cleaned and rebuilt, new plugs and had numerous other minor issues resolved. The water pump hasn't been overhauled, but the mechanics have all claimed that the impeller is fine as the engine produces a sufficient "pee-stream." However, the big problem hasn't been solved. When the engine hasn't been used overnight or for a few days, it starts on the first or second pull and will idle OK. It will also run fine under full power on that first run and push our 14ft aluminum skiff at 20-25 miles an hour. From that point the reliability goes downstream fast and has me ready to use it as an anchor. The fun starts when the engine will not idle after being run at full or half throttle. It will also not restart easily if it is hot and/or has stalled out. You can sometimes get it started if you override the neutral-start interlock and immediately give more throttle than the "over-rev" limiter in neutral will allow. I know it's dangerous and for that reason won't let my kids drive it. Letting it sit for a while, an hour or so, gives you a better shot of restarting it, but not reliably and/or keeping it running. Ironically, when I've picked it up, all the shops have told me how great it runs in the test tank; they claim it starts right up, idles nicely and runs as well as can be expected for this age motor. I don't doubt that it does (in their test tanks), but I think they're all missing something. On the other hand, I'm sure they think I'm neurotic about this engine. Any thoughts suggestions or insights would be greatly appreciated. Bill Lav Larry Extremely intelligent life must exist in the universe. You can tell because they never tried to contact us. |
#4
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Low speed winding to be specific. (assuming Jonnyrudes have one)
-W "Larry" wrote in message ... I'm leaning on a bad stator on this one. When they get hot, the windings expand and if something's broken loose the spark sucks until it gets cool again. When it's cool and running fine, hook one plug wire up to an external spark plug that's grounded to the block so you can see the spark. Note how the spark looks. Then, when it's running like crap, do that again and see if you don't see a real thin, wimpy weak spark that compression can blow out the fire to..... I had a stator on an Evinrude 3-cyl 55 that worked great whenever a mechanic was looking at it because, in his haste, he never got the motor hot enough to make it fail.... Gets hot under that flywheel..... On Tue, 12 Aug 2003 02:27:34 GMT, "Bill Lavernoich" wrote: The problem with the 15 hp is as follows. I bought this motor two years ago from a guy who claimed to be selling it for the wife of a deceased friend. He didn't have much info on the engine except to say it had not been run in at least 5 years. (I willing to bet it was like 10 or more years.) Although originally I could not get it started, I've now had it serviced by three different repair shops, all with OMC backgrounds. It's been decarbonized, had the carburetor cleaned and rebuilt, new plugs and had numerous other minor issues resolved. The water pump hasn't been overhauled, but the mechanics have all claimed that the impeller is fine as the engine produces a sufficient "pee-stream." However, the big problem hasn't been solved. When the engine hasn't been used overnight or for a few days, it starts on the first or second pull and will idle OK. It will also run fine under full power on that first run and push our 14ft aluminum skiff at 20-25 miles a n hour. From that point the reliability goes downstream fast and has me ready to use it as an anchor. The fun starts when the engine will not idle after being run at full or half throttle. It will also not restart easily if it is hot and/or has stalled out. You can sometimes get it started if you override the neutral-start interlock and immediately give more throttle than the "over-rev" limiter in neutral will allow. I know it's dangerous and for that reason won't let my kids drive it. Letting it sit for a while, an hour or so, gives you a better shot of restarting it, but not reliably and/or keeping it running. Ironically, when I've picked it up, all the shops have told me how great it runs in the test tank; they claim it starts right up, idles nicely and runs as well as can be expected for this age motor. I don't doubt that it does (in their test tanks), but I think they're all missing something. On the other hand, I'm sure they think I'm neurotic about this engine. Any thoughts suggestions or insights would be greatly appreciated. Bill Lav Larry Extremely intelligent life must exist in the universe. You can tell because they never tried to contact us. |
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