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Replace alternator in 5.7 Mercruiser?
To make sure the insurance company did not have a loophole, you could just
add brackets and a marinized alternator. Figure out the proper pulley size to get a good generating output at the normal engine RPM's. Bill "Terry" wrote in message ... Calif Bill wrote: It is an automotive / truck alternator. With the only changes screening for all openings. Prevents flame propagation from nisde to outside the alternator. Same for starters. Bill "Jere Lull" wrote in message ... R Kelly wrote: "Jere Lull" wrote in message .. . seeray wrote: The answer is simple, if you feel it needs to be replaced before you go, then do it. Peace of mind is worth alot more than the alternator I agree, except: keep the known working one as a spare. [every once in a while, a "new" one fails pretty early.] They can last as long as car alternators, if the engine compartment is fairly hospitable, since they usually ARE car alternators. Marine alternators are intrinsically sealed. Anything less would promote ignition potential in the engine compartment. One would be ill advised to put an automotive alternator in an engine compartment, for an number of other reasons as well. BK Oops! I intended to say "usually are essentially" car alternators. The Hitachi on our Yanmar sure looks like the one in my old car. I'm sure there are differences, but the base technology isn't going to be too different. -- Jere Lull Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD) Xan's Pages: http://members.dca.net/jerelull/X-Main.html Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/ So; in a non gasoline situation (Volvo MD1B diesel) would you advise using a truck/car alternator? The existing engine has an a 12 volt 8 amp. Bosch starter-generator. It's difficult to keep the battery charged with that. We would like the charging capacity of say a 60 to 100 ampere alternator. Any advice welcomed. Terry. |
#2
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Replace alternator in 5.7 Mercruiser?
Terry wrote:
Calif Bill wrote: It is an automotive / truck alternator. With the only changes screening for all openings. Prevents flame propagation from nisde to outside the alternator. Same for starters. Bill "Jere Lull" wrote in message .. . R Kelly wrote: Marine alternators are intrinsically sealed. Anything less would promote ignition potential in the engine compartment. One would be ill advised to put an automotive alternator in an engine compartment, for an number of other reasons as well. BK Oops! I intended to say "usually are essentially" car alternators. The Hitachi on our Yanmar sure looks like the one in my old car. I'm sure there are differences, but the base technology isn't going to be too different. -- Jere Lull So; in a non gasoline situation (Volvo MD1B diesel) would you advise using a truck/car alternator? The existing engine has an a 12 volt 8 amp. Bosch starter-generator. It's difficult to keep the battery charged with that. We would like the charging capacity of say a 60 to 100 ampere alternator. Any advice welcomed. Terry. Since some of our sister boats have that same engine, I'd recommend what I recommend to them -- for weekend use -- a relativley small solar charger (5-15 watts) to bring things up to snuff while we're away. Starter/generator combos were a good idea before alternators came into vogue. Alternators are MUCH better, but still not exactly perfect for sailboat auxiliaries. Our 55 amp Hitachi won't deliver more than about 5 amps under normal conditions after a few minutes' snap charge. Even that alternator will seriously strain the belt and Yanmar 2GM20 when we have to bring a seriously-discharged battery up. I wouldn't go above that power output without a double pulley (want one now), and I'm not sure the MD1B will take that strain. I'm not happy with the time it takes the "basically automotive" alternator to bring our batteries up to reasonable levels. As it is, I'm real happy with 12.25v and will put up with 12.0v as we turn on the anchor light for the night. I definitely wouldn't go with a plain truck/car alternator as there are serious differences, the primary one being that the boat ones are expected to be in a hostile -- hot and humid -- environment. If we go cruising amongst the islands, I think our primary power will be from larger solar cells. We'd probably add a 3 or 4 stage alternator for safety's sake, but that's more expensive than solar. -- Jere Lull Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD) Xan's Pages: http://members.dca.net/jerelull/X-Main.html Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/ |
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