Re: Stus-List Relocating the Yanmar key now alternator..
If your alternator is not working then you should simple get an alternator buzzer alarm. This assumes your alternator alarm is working. When you turn your key on to provide power before actually cranking the engine the engine, you should hear the buzzer and see possible two lights on. If you don’t have lights, you can disconnect the wire on the engine oil pressure switch. The pressure switch provide alarm ground when there is no(or low) pressure. Unplug this wire and keep it from grounding against the engine block and turn the key on, if you get a buzzer then the alternator alarm is working. Some of the confusion regarding killing or not killing an alternator may likely stems to the the type of alternator and how it’s connected. Most Yanmars come with internally regulated Hitachi alternators. Maine Sail called these alternators “ dumber than a pound of beetle poop”. My old C&C 29 had the standard 35A Hitachi. The key switch would only provide 12V power to a line through an alternator alarm buzzer then to the alternators “lamp” connection. When the alternator was not spinning, the “lamp” connection provided the ground for the buzzer to alarm. When the alternator was spinning and working, it provided 14V at the “Lamp” connector and since it was also providing 14V to the battery, the alarm buzzer saw 14V before and after (i.e. zero volt difference) and stopped buzzing. The alternator also had a connection (top of T-connector) for the battery sensing used by the internal regulator. In this case, the sense was connected via a short loop to the battery connection. So for this arrangement, I would guess that shutting off the key switch would not harm the alternator. And I know from experience this to be the case. I have heard that some old internal regulated alternators do not have a sense connection but rather likely use the lamp connection for sensing. Or maybe even some sense connections are connected to the a key powered switch. In these cases, I could see how an alternator could be harmed by a sudden disconnect of the sense voltage. - Paul E. 1981 C&C 38 Landfall S/V Johanna Rose Carrabelle, FL http://svjohannarose.blogspot.com/ > On Jul 20, 2016, at 12:00 PM, cnc-list-requ...@cnc-list.com wrote: > > Date: Wed, 20 Jul 2016 08:54:27 -0600 > From: Lorne Serpa mailto:lorne.se...@gmail.com>> > To: cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com> > Subject: Re: Stus-List Relocating the Yanmar key now alternator.. > Message-ID: ><mailto:CAL=lx5v_6uo_r-ieuxmgm4ahmaw_bbxjgs5q2ytjtpzr-dp...@mail.gmail.com>> > Content-Type: text/plain; charset="utf-8" > > Hum, I. New to this boat and boats with diesel engines. Numerous times > past couple weeks have turned key off without killing the engine. I have a > 20gm. How do I know if I did damage? Check battery voltage while engine is > running? Should be 13.5 or so? > > Lorne Serpa > C&C 30MKII 1988 > Friendship, MD > On Jul 20, 2016 12:50 AM, "Leslie Paal via CnC-List" <mailto:cnc-list@cnc-list.com>> ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
It is hard to say for sure what your regulator is going to control voltage at and without know what type of batteries you have it is hard to know what voltage it should be. Normal car alternators control at about 14.4v. A lead-acid battery is considered to be fully charged when the resting voltage is at 12.7v... But that is after it has set for a while or once the the "overcharge" has been removed. You most likely did no damage if the alternator is still putting out a charge and 13.5v is definitely a charge. Josh Muckley S/V Sea Hawk 1989 C&C 37+ Solomons, MD On Jul 20, 2016 10:55 AM, "Lorne Serpa via CnC-List" wrote: > Hum, I. New to this boat and boats with diesel engines. Numerous times > past couple weeks have turned key off without killing the engine. I have a > 20gm. How do I know if I did damage? Check battery voltage while engine is > running? Should be 13.5 or so? > > Lorne Serpa > C&C 30MKII 1988 > Friendship, MD > On Jul 20, 2016 12:50 AM, "Leslie Paal via CnC-List" < > cnc-list@cnc-list.com> wrote: > >> Small correction: >> "The sudden high >> current overheats the diodes and they fail open" >> When the battery is disconnected while the alternator is charging the >> existing field current will generate a high voltage spike that exceeds the >> reverse voltage breakdown value. Normal diodes are rated for 60-100V >> reverse voltage. The spike can be lot more; depending how high was the >> charging current (more>higher). The P/N junction will punch through, the >> resulting localized current can make it open or short. >> >> Overloading forward (normal direction) current will heat the chip and the >> carefully placed 'impurities' will migrate and make the diode a little or >> lot leaky. Unless you fuse the internal connection, the open. >> >> Leslie. >> Phoenix C&C32 1983 >> >> >> On Tue, 7/19/16, Josh Muckley via CnC-List wrote: >> >> Subject: Re: Stus-List Relocating the Yanmar key now alternator.. >> To: "C&C List" >> Cc: "Josh Muckley" >> Date: Tuesday, July 19, 2016, 9:31 AM >> >> I have heard >> all of this before and am still electrically confused. I >> have a few theories but no proof. In the face of my >> theories is the fact that it is not consistently >> repeatable. So here goes. >> Turn the battery off while running and the >> alternator suddenly goes to full output kinda like shifting >> to 1st while going 70mph. I get that. The sudden high >> current overheats the diodes and they fail open. >> Turn the key off while running and one of two >> things happens. 1st option is that nothing about the >> alternator is wired to the ignition and nothing happens. I >> >> ___ >> >> This list is supported by the generous donations of our members. If you >> like what we do, please help us pay for our costs by donating. All >> Contributions are greatly appreciated! >> > > ___ > > This list is supported by the generous donations of our members. If you > like what we do, please help us pay for our costs by donating. All > Contributions are greatly appreciated! > > ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Stus-List Relocating the Yanmar key now alternator..
Hi Lorne, If your charging warning light is not "on" constantly, you should be OK. It appears the 2GM's are not as likely to be affected. Good Luck, Francois Rivard 1990 34+ "Take five" Lake Lanier, GA Date: Wed, 20 Jul 2016 08:29:47 -0600 From: Message: 2 Date: Wed, 20 Jul 2016 08:54:27 -0600 From: Lorne Serpa To: cnc-list@cnc-list.com Subject: Re: Stus-List Relocating the Yanmar key now alternator.. Message-ID: Content-Type: text/plain; charset="utf-8" Hum, I. New to this boat and boats with diesel engines. Numerous times past couple weeks have turned key off without killing the engine. I have a 20gm. How do I know if I did damage? Check battery voltage while engine is running? Should be 13.5 or so? Lorne Serpa C&C 30MKII 1988 Friendship, MD On Jul 20, 2016 12:50 AM, "Leslie Paal via CnC-List" ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
Hum, I. New to this boat and boats with diesel engines. Numerous times past couple weeks have turned key off without killing the engine. I have a 20gm. How do I know if I did damage? Check battery voltage while engine is running? Should be 13.5 or so? Lorne Serpa C&C 30MKII 1988 Friendship, MD On Jul 20, 2016 12:50 AM, "Leslie Paal via CnC-List" wrote: > Small correction: > "The sudden high > current overheats the diodes and they fail open" > When the battery is disconnected while the alternator is charging the > existing field current will generate a high voltage spike that exceeds the > reverse voltage breakdown value. Normal diodes are rated for 60-100V > reverse voltage. The spike can be lot more; depending how high was the > charging current (more>higher). The P/N junction will punch through, the > resulting localized current can make it open or short. > > Overloading forward (normal direction) current will heat the chip and the > carefully placed 'impurities' will migrate and make the diode a little or > lot leaky. Unless you fuse the internal connection, the open. > > Leslie. > Phoenix C&C32 1983 > > -------- > On Tue, 7/19/16, Josh Muckley via CnC-List wrote: > > Subject: Re: Stus-List Relocating the Yanmar key now alternator.. > To: "C&C List" > Cc: "Josh Muckley" > Date: Tuesday, July 19, 2016, 9:31 AM > > I have heard > all of this before and am still electrically confused. I > have a few theories but no proof. In the face of my > theories is the fact that it is not consistently > repeatable. So here goes. > Turn the battery off while running and the > alternator suddenly goes to full output kinda like shifting > to 1st while going 70mph. I get that. The sudden high > current overheats the diodes and they fail open. > Turn the key off while running and one of two > things happens. 1st option is that nothing about the > alternator is wired to the ignition and nothing happens. I > > ___ > > This list is supported by the generous donations of our members. If you > like what we do, please help us pay for our costs by donating. All > Contributions are greatly appreciated! > ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
Small correction: "The sudden high current overheats the diodes and they fail open" When the battery is disconnected while the alternator is charging the existing field current will generate a high voltage spike that exceeds the reverse voltage breakdown value. Normal diodes are rated for 60-100V reverse voltage. The spike can be lot more; depending how high was the charging current (more>higher). The P/N junction will punch through, the resulting localized current can make it open or short. Overloading forward (normal direction) current will heat the chip and the carefully placed 'impurities' will migrate and make the diode a little or lot leaky. Unless you fuse the internal connection, the open. Leslie. Phoenix C&C32 1983 On Tue, 7/19/16, Josh Muckley via CnC-List wrote: Subject: Re: Stus-List Relocating the Yanmar key now alternator.. To: "C&C List" Cc: "Josh Muckley" Date: Tuesday, July 19, 2016, 9:31 AM I have heard all of this before and am still electrically confused. I have a few theories but no proof. In the face of my theories is the fact that it is not consistently repeatable. So here goes. Turn the battery off while running and the alternator suddenly goes to full output kinda like shifting to 1st while going 70mph. I get that. The sudden high current overheats the diodes and they fail open. Turn the key off while running and one of two things happens. 1st option is that nothing about the alternator is wired to the ignition and nothing happens. I ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Stus-List Relocating the Yanmar key now alternator..
Rather than filling pages and inboxes, Am assuming the subject is not of interest to most in this level of detail. I Have replied in more detail, and with a hypothesis, to josh and JF off list...(who may not be all that interested either... Lol.) Again, this site is well worth exploring on this subject. The author has provided very clear explanations of alternator theory, in two levels of detail. http://www.pirate4x4.com/tech/billavista/Wiring/Part2/ Dave Message: 1 Date: Tue, 19 Jul 2016 16:31:09 + From: Josh Muckley To: "C&C List" Subject: Re: Message-ID: Content-Type: text/plain; charset="utf-8" I have heard all of this before and am still electrically confused. I have a few theories but no proof. In the face of my theories is the fact that it is not consistently repeatable. So here goes. Turn the battery off while running and the alternator suddenly goes to full output kinda like shifting to 1st while going 70mph. I get that. The sudden high current overheats the diodes and they fail open. Turn the key off while running and one of two things happens. 1st option is that nothing about the alternator is wired to the ignition and nothing happens. I believe that this is the situation with the ignition system in the video I posted earlier in this thread. As mentioned by others the battery and voltage sensing lines are basically directly connected to the battery so turning the key on or off doesn't affect anything. I also think this is the slow and very low battery drain which someone else mentioned. The 2nd option is that the ignition is attached to the sensing circuit as in the schematic. The switch turns on and off the regulator and subsequently the rotor field. This would apply to alternators with either the internal or external regulator. As the regulator is turned off this might be causing a momentary high counter electromotive force or an unopposed stator current (surge). Or maybe a sudden full reverse bias current of the diodes. This is obviously the confusing part. I've never figured it out and until someone else explains it I don't plan to make a habit of turning off the switch or the battery. Josh Muckley S/V Sea Hawk 1989 C&C 37+ Solomons, MD Couple other data points: ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
Hi Dave, Thanks for the added stuff. Actually it seems to explain it all: Why some alternators fry and some don't: The key here is the "Self Exciting" part. The self exciting alternators don't need the ignition return side at all. Basically all your key does is turn-off the instrument panel (And annoying buzzer) and disable the starter. Your alternator's function is truly not affected by the key . This other site I saw explains that very clearly : https://alternatorparts.com/what-is-a-self-exciting-alternator.html That also explain the runaway voltage situation: It says: "Remember the diagram of the pulsed DC output from the alternator and the fact that the battery acts as a large filter or cushion in the system. " so basically from looking at the schema you can see that in the non-self exciting alternator like mine the ignition / charging light is connected straight into the alternator. If you switch the battery off while the engine is running since it's a diesel it keeps chugging / the alternator keeps producing juice and the voltage regulator will take the brunt of the stator's output which causes the voltage spike.. Bottom line, it appears the 2QM 2GM engines have self-exciting alternators and the 3GM's don't. -Francois Rivard 1990 34+ "Take Five" Lake Lanier, GA "While this clarifies the role of that supply and why the engine will run fine, (and for many of us, without apparent damage) with the key removed. (once spinning, the alternator excites itself,) it does not explain the failure experienced by only some of us, or the absence of warning in the various factory docs. Based on my extensive online research ;-) the failure experienced is as if the alternator is seeing no load, (i.e. battery disconnected) or as if it is running unregulated, with a fully energized field coil. I wonder if the failing alternators have an issue (i.e. failed regulator?) that is hidden by the presence of the independent field current supply, and only becomes exposed in its absence" Regards François Rivard 4111 Northside Pkwy, Nw Big Data Black Belt Certified Level 3 IT Specialist Thought Leader Atlanta, 30327-3015 USA IBM Sales & Distribution, Software Sales Mobile: 770-639-0429 e-mail: jfriv...@us.ibm.com From: Dave Syer To: "C&c Stus List" , Jean-Francois J Rivard/Atlanta/IBM@IBMUS Date: 07/19/2016 01:35 PM Subject:Re: Stus-List Relocating the Yanmar key now alternator.. There is a great explanation of all this here: http://www.pirate4x4.com/tech/billavista/Wiring/Part2/ And, to complete your commentary below, a lucid explanation of the role of the key switch circuit in our engines. >>>snip Field Current Supply The field current supply is provided from one of two different sources, depending on the state of the alternator. When the engine is not running and the alternator is not spinning and producing electricity, the field current supply comes from the vehicle's battery, via the ignition switch and alternator warning lamp (if equipped). We'll go into more detail on the warning lamp shortly. The process of supplying battery voltage to "kick-start" or "prime" the alternator is known as "exciting" the alternator, and the wire that carries the current from the alternator warning lamp to the appropriate voltage regulator terminal is known as the "exciter" wire. A few special alternators do not have this wire and are known as "self-exciting" - we'll cover this in more detail in the wiring section. After the engine is started, and the alternator is generating electricity the diode trio feeds the alternator output back to the voltage regulator to serve as the field current supply. Theoretically, once up to speed, the alternator is self sustaining, and the car will run without a battery until it is shut off (as long as system demand does not exceed alternator output capacity). However - you should never disconnect the battery in a running vehicle as doing so can cause voltage surges that can damage not only the voltage regulator, but also other on-board electrical equipment - particularly computer-controlled devices. Remember the diagram of the pulsed DC output from the alternator and the fact that the battery acts as a large filter or cushion in the system. Note that the field current is much smaller than the output current produced in the stator windings. For example, to produce 70 amperes of DC, the field current required will be less than 2 amperes. >>>snip While this clarifies the role of that supply and why the engine will run fine, (and for many of us, without apparent damage) with the key removed. (once spinning, the alternator excites itself,) it does not explain the failure experienced by only some of
Re: Stus-List Relocating the Yanmar key now alternator..
There is a great explanation of all this here: http://www.pirate4x4.com/tech/billavista/Wiring/Part2/ And, to complete your commentary below, a lucid explanation of the role of the key switch circuit in our engines. >>>snip Field Current Supply The field current supply is provided from one of two different sources, depending on the state of the alternator. When the engine is not running and the alternator is not spinning and producing electricity, the field current supply comes from the vehicle's battery, via the ignition switch and alternator warning lamp (if equipped). We'll go into more detail on the warning lamp shortly. The process of supplying battery voltage to "kick-start" or "prime" the alternator is known as "exciting" the alternator, and the wire that carries the current from the alternator warning lamp to the appropriate voltage regulator terminal is known as the "exciter" wire. A few special alternators do not have this wire and are known as "self-exciting" - we'll cover this in more detail in the wiring section. After the engine is started, and the alternator is generating electricity the diode trio feeds the alternator output back to the voltage regulator to serve as the field current supply. Theoretically, once up to speed, the alternator is self sustaining, and the car will run without a battery until it is shut off (as long as system demand does not exceed alternator output capacity). However - you should never disconnect the battery in a running vehicle as doing so can cause voltage surges that can damage not only the voltage regulator, but also other on-board electrical equipment - particularly computer-controlled devices. Remember the diagram of the pulsed DC output from the alternator and the fact that the battery acts as a large filter or cushion in the system. Note that the field current is much smaller than the output current produced in the stator windings. For example, to produce 70 amperes of DC, the field current required will be less than 2 amperes. >>>snip While this clarifies the role of that supply and why the engine will run fine, (and for many of us, without apparent damage) with the key removed. (once spinning, the alternator excites itself,) it does not explain the failure experienced by only some of us, or the absence of warning in the various factory docs. Based on my extensive online research ;-) the failure experienced is as if the alternator is seeing no load, (i.e. battery disconnected) or as if it is running unregulated, with a fully energized field coil. I wonder if the failing alternators have an issue (i.e. failed regulator?) that is hidden by the presence of the independent field current supply, and only becomes exposed in its absence? Dave Message: 2 Date: Tue, 19 Jul 2016 09:21:52 -0400 From: "Jean-Francois J Rivard" To: "syerd...@gmail.com" Cc: cnc-list@cnc-list.com Subject: Re: Stus-List Relocating the Yanmar key now alternator.. Message-ID: < of4343dba2.fa97e163-on00257ff5.004567a8-85257ff5.00496...@notes.na.collabserv.com > Content-Type: text/plain; charset="us-ascii" Hi Dave, Here's how I understood the whole thing. An alternator's design is basically the reverse of a regular DC motor with an added twist.. On a regular DC motor the windings (Electro magnets) are on the spinning armature and there are permanent magnets attached to the housing. You add voltage to it: The windings are energized, they produce a magnetic force opposite to the permanent magnet on the housing, the motor spins. The more voltage, the stronger the electro magnet on the armature becomes, the faster it spins On an alternator, the windings are on the housing (Stator) and the magnets are spinning with the shaft (Rotor). You spin the alternator, the magnets fields excite the windings, A/C electricity is produced. The alternator's added twist is that the magnets are not permanent, they are electro-magnets with their own winding. The genius here is that it makes the magnets adjustable where their strength (And the Alternator's output) can be controlled by varying the voltage applied to them while still being driven at the same RPM.. Voila :-) The alternator I burned was most assuredly the original Yanmar unit.. It had the funky looking fan, was stamped 'Yanmar", and was painted the same color as the rest of the engine. I guess the one on your 2GM is somehow different than what was on my 3GM.. ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
I have heard all of this before and am still electrically confused. I have a few theories but no proof. In the face of my theories is the fact that it is not consistently repeatable. So here goes. Turn the battery off while running and the alternator suddenly goes to full output kinda like shifting to 1st while going 70mph. I get that. The sudden high current overheats the diodes and they fail open. Turn the key off while running and one of two things happens. 1st option is that nothing about the alternator is wired to the ignition and nothing happens. I believe that this is the situation with the ignition system in the video I posted earlier in this thread. As mentioned by others the battery and voltage sensing lines are basically directly connected to the battery so turning the key on or off doesn't affect anything. I also think this is the slow and very low battery drain which someone else mentioned. The 2nd option is that the ignition is attached to the sensing circuit as in the schematic. The switch turns on and off the regulator and subsequently the rotor field. This would apply to alternators with either the internal or external regulator. As the regulator is turned off this might be causing a momentary high counter electromotive force or an unopposed stator current (surge). Or maybe a sudden full reverse bias current of the diodes. This is obviously the confusing part. I've never figured it out and until someone else explains it I don't plan to make a habit of turning off the switch or the battery. Josh Muckley S/V Sea Hawk 1989 C&C 37+ Solomons, MD Couple other data points: - The diesel mechanic gave me a huge DUH ! when I explained what had happened.. He said, you just learned the hard way that you should never turn off the ignition key on a diesel while it's running. What happened was punishment for my brain fart.. The guy fixes diesels for a living - The alternator shop I talked to said the exact same thing. Burned diodes blah blah, happens all the time to new diesel owners.. - Francois Rivard 1990 34+ "Take Five" lake Lanier, GA ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated! ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
I guess I didn't know what I was doing wrong - I had an overheating problem which was intermittent. The annoying little buzzer would blast away but I still had water flowing through the system (I guess not quite enough to satisfy the sensor). After more than a few minutes of this, I turned the key (or in my case the pull switch off ) which turned off the buzzer and tach and light. Motor still ran alternator seemed to be putting out - still is about three years later. I guess I was lucky - still have same alternator and have fixed the blockage in the water system - a small piece of an impeller which was petrified and stuck near one of the zincs - and which must have been there since before 1994 when I bought the boat - all the impellers I have changed over the years came out in one piece. Now have more flow and no noise. 1980 Yanmar 2QM15. Gary 30-1 From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Jean-Francois J Rivard via CnC-List Sent: Tuesday, July 19, 2016 9:22 AM To: syerd...@gmail.com Cc: Jean-Francois J Rivard ; cnc-list@cnc-list.com Subject: Re: Stus-List Relocating the Yanmar key now alternator.. Hi Dave, Here's how I understood the whole thing. An alternator's design is basically the reverse of a regular DC motor with an added twist.. * On a regular DC motor the windings (Electro magnets) are on the spinning armature and there are permanent magnets attached to the housing. You add voltage to it: The windings are energized, they produce a magnetic force opposite to the permanent magnet on the housing, the motor spins. The more voltage, the stronger the electro magnet on the armature becomes, the faster it spins * * On an alternator, the windings are on the housing (Stator) and the magnets are spinning with the shaft (Rotor). * You spin the alternator, the magnets fields excite the windings, A/C electricity is produced. * The alternator's added twist is that the magnets are not permanent, they are electro-magnets with their own winding. The genius here is that it makes the magnets adjustable where their strength (And the Alternator's output) can be controlled by varying the voltage applied to them while still being driven at the same RPM.. Voila :-) The alternator I burned was most assuredly the original Yanmar unit.. It had the funky looking fan, was stamped 'Yanmar", and was painted the same color as the rest of the engine. I guess the one on your 2GM is somehow different than what was on my 3GM.. -Francois 1990 34+ "Take Five" Lake Lanier, GA From:"syerd...@gmail.com <mailto:syerd...@gmail.com> " mailto:syerd...@gmail.com> > To:Jean-Francois J Rivard/Atlanta/IBM@IBMUS Cc:cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com> Date:07/19/2016 08:14 AM Subject:Re: Relocating the Yanmar key now alternator.. _ Thanks JF. An interesting read here. http://www.autoshop101.com/forms/alt_bwoh.pdf A decent corrected alternator diagram here. Post #15 http://www.ybw.com/forums/showthread.php?224370-What-s-the-R-connection-for- on-a-Yanmar-Hitachi-alternator/page2 So, if I understand correctly the key switch energizes the starting circuit, the warning indicators and provides a reference battery voltage to the voltage regulator, which regulates the voltage to the field coil and thereby the alternator output. More study required to truly grasp the theory, but am still grappling with why "no key/blown fuse = alternator destruction", and why some have had alternators fail and some did not. Also, keyless operation is not discussed (that I could find) in the owners manual or the shop manual, which seems strange. Is it possible that OE Yanmar alternators are of a design that incorporates safeguards appropriate to this situation, and that the failed alternators are of a different type? On Jul 18, 2016, at 1:25 PM, Jean-Francois J Rivard mailto:jfriv...@us.ibm.com> > wrote: Hi Dave, It's possible your alternator is internally wired differently. As for the rest of us (again, what I was told) the diodes are supposedly there meant to both turn the a/c current into dc for use by the batteries and act fuse-like to prevent the possibility some kind of much worse (Overheat / fire perhaps? ) alternator self destruction. All I knew at the time was for 78 bucks and 45 or so minutes of wrenching I could make it all good again and have the peace of mind associated with replacing a 20 year old alternator with a brand new unit. Now that I'm looking into it that appears the catastrophic failure would to be related to the field coils which are energized as the alternator turns and their voltage is regulated by the battery / voltage regulator. Apparently, if left unchecked (With a disconnected battery, open "ignition" circuit) the output voltage could go t
Stus-List Relocating the Yanmar key now alternator..
Couple other data points: The diesel mechanic gave me a huge DUH ! when I explained what had happened.. He said, you just learned the hard way that you should never turn off the ignition key on a diesel while it's running. What happened was punishment for my brain fart.. The guy fixes diesels for a living The alternator shop I talked to said the exact same thing. Burned diodes blah blah, happens all the time to new diesel owners.. Francois Rivard 1990 34+ "Take Five" lake Lanier, GA ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
Hi Dave, Here's how I understood the whole thing. An alternator's design is basically the reverse of a regular DC motor with an added twist.. On a regular DC motor the windings (Electro magnets) are on the spinning armature and there are permanent magnets attached to the housing. You add voltage to it: The windings are energized, they produce a magnetic force opposite to the permanent magnet on the housing, the motor spins. The more voltage, the stronger the electro magnet on the armature becomes, the faster it spins On an alternator, the windings are on the housing (Stator) and the magnets are spinning with the shaft (Rotor). You spin the alternator, the magnets fields excite the windings, A/C electricity is produced. The alternator's added twist is that the magnets are not permanent, they are electro-magnets with their own winding. The genius here is that it makes the magnets adjustable where their strength (And the Alternator's output) can be controlled by varying the voltage applied to them while still being driven at the same RPM.. Voila :-) The alternator I burned was most assuredly the original Yanmar unit.. It had the funky looking fan, was stamped 'Yanmar", and was painted the same color as the rest of the engine. I guess the one on your 2GM is somehow different than what was on my 3GM.. -Francois 1990 34+ "Take Five" Lake Lanier, GA From: "syerd...@gmail.com" To: Jean-Francois J Rivard/Atlanta/IBM@IBMUS Cc: cnc-list@cnc-list.com Date: 07/19/2016 08:14 AM Subject:Re: Relocating the Yanmar key now alternator.. Thanks JF. An interesting read here. http://www.autoshop101.com/forms/alt_bwoh.pdf A decent corrected alternator diagram here. Post #15 http://www.ybw.com/forums/showthread.php?224370-What-s-the-R-connection-for-on-a-Yanmar-Hitachi-alternator/page2 So, if I understand correctly the key switch energizes the starting circuit, the warning indicators and provides a reference battery voltage to the voltage regulator, which regulates the voltage to the field coil and thereby the alternator output. More study required to truly grasp the theory, but am still grappling with why "no key/blown fuse = alternator destruction", and why some have had alternators fail and some did not. Also, keyless operation is not discussed (that I could find) in the owners manual or the shop manual, which seems strange. Is it possible that OE Yanmar alternators are of a design that incorporates safeguards appropriate to this situation, and that the failed alternators are of a different type? On Jul 18, 2016, at 1:25 PM, Jean-Francois J Rivard wrote: Hi Dave, It's possible your alternator is internally wired differently. As for the rest of us (again, what I was told) the diodes are supposedly there meant to both turn the a/c current into dc for use by the batteries and act fuse-like to prevent the possibility some kind of much worse (Overheat / fire perhaps? ) alternator self destruction. All I knew at the time was for 78 bucks and 45 or so minutes of wrenching I could make it all good again and have the peace of mind associated with replacing a 20 year old alternator with a brand new unit. Now that I'm looking into it that appears the catastrophic failure would to be related to the field coils which are energized as the alternator turns and their voltage is regulated by the battery / voltage regulator. Apparently, if left unchecked (With a disconnected battery, open "ignition" circuit) the output voltage could go to a couple hundred volts which could potentially make the regulator circuitry immolate itself or something to that effect. With the typical setup the diodes burn-out first and prevent catastrophic damage. See here for more details: http://www.pangolin.co.nz/node/16 -Francois Rivard 1990 34+ "Take Five" Lake Lanier, GA Message: 2 Date: Mon, 18 Jul 2016 08:38:01 -0400 From: Dave Syer To: "C&c Stus List" Subject: Stus-List Relocating the Yanmar key now alternator.. Message-ID: < CAD7ywJNLTLNEHS97dz1oBPaK74ymNc-TLCLL=zsojmhkart...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" Interesting discussion. So, I have run my 1985 2gm Yanmar briefly with the key removed and no apparent harm was done. The manual does say never to run it with the battery disconnected. Now, when I check the schematic, (and my engine) there is a 30A tubular fuse in series with the key switch. Therefore a blown fuse = an open key switch, and would cause the same damage to the alternator. This does not make a lot of sense to me. Other than adequate knowledge, am I missing something? See below. ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
Thanks JF. An interesting read here. http://www.autoshop101.com/forms/alt_bwoh.pdf A decent corrected alternator diagram here. Post #15 http://www.ybw.com/forums/showthread.php?224370-What-s-the-R-connection-for-on-a-Yanmar-Hitachi-alternator/page2 So, if I understand correctly the key switch energizes the starting circuit, the warning indicators and provides a reference battery voltage to the voltage regulator, which regulates the voltage to the field coil and thereby the alternator output. More study required to truly grasp the theory, but am still grappling with why "no key/blown fuse = alternator destruction", and why some have had alternators fail and some did not. Also, keyless operation is not discussed (that I could find) in the owners manual or the shop manual, which seems strange. Is it possible that OE Yanmar alternators are of a design that incorporates safeguards appropriate to this situation, and that the failed alternators are of a different type? > On Jul 18, 2016, at 1:25 PM, Jean-Francois J Rivard > wrote: > > Hi Dave, > > It's possible your alternator is internally wired differently. As for the > rest of us (again, what I was told) the diodes are supposedly there meant to > both turn the a/c current into dc for use by the batteries and act fuse-like > to prevent the possibility some kind of much worse (Overheat / fire perhaps? > ) alternator self destruction. All I knew at the time was for 78 bucks and 45 > or so minutes of wrenching I could make it all good again and have the peace > of mind associated with replacing a 20 year old alternator with a brand new > unit. > > Now that I'm looking into it that appears the catastrophic failure would to > be related to the field coils which are energized as the alternator turns and > their voltage is regulated by the battery / voltage regulator. Apparently, > if left unchecked (With a disconnected battery, open "ignition" circuit) the > output voltage could go to a couple hundred volts which could potentially > make the regulator circuitry immolate itself or something to that effect. > With the typical setup the diodes burn-out first and prevent catastrophic > damage. > > See here for more details: http://www.pangolin.co.nz/node/16 > > > -Francois Rivard > 1990 34+ "Take Five" > Lake Lanier, GA > > > > > Message: 2 > Date: Mon, 18 Jul 2016 08:38:01 -0400 > From: Dave Syer > To: "C&c Stus List" > Subject: Stus-List Relocating the Yanmar key now alternator.. > Message-ID: > > > Content-Type: text/plain; charset="utf-8" > > Interesting discussion. So, I have run my 1985 2gm Yanmar briefly with > the key removed and no apparent harm was done. The manual does say never > to run it with the battery disconnected. > > Now, when I check the schematic, (and my engine) there is a 30A tubular > fuse in series with the key switch. Therefore a blown fuse = an open key > switch, and would cause the same damage to the alternator. This does not > make a lot of sense to me. Other than adequate knowledge, am I missing > something? See below. > > ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Re: Stus-List Relocating the Yanmar key now alternator..
The worst part is that the test is potentially destructive. If you turn the ignition off and nothing happens, you know that you can do that. On the other hand, if you do that and you fry the diodes, you know that you shouldn't, but you also need to replace the alternator. And trying it on someone else's boat is inconclusive. Marek Sent from my Bell Samsung device over Canada's largest network. Original message From: Jean-Francois J Rivard via CnC-List Date: 7/18/16 13:27 (GMT-05:00) To: cnc-list@cnc-list.com Cc: Jean-Francois J Rivard , syerd...@gmail.com Subject: Stus-List Relocating the Yanmar key now alternator.. Hi Dave, It's possible your alternator is internally wired differently. As for the rest of us (again, what I was told) the diodes are supposedly there meant to both turn the a/c current into dc for use by the batteries and act fuse-like to prevent the possibility some kind of much worse (Overheat / fire perhaps? ) alternator self destruction. All I knew at the time was for 78 bucks and 45 or so minutes of wrenching I could make it all good again and have the peace of mind associated with replacing a 20 year old alternator with a brand new unit. Now that I'm looking into it that appears the catastrophic failure would to be related to the field coils which are energized as the alternator turns and their voltage is regulated by the battery / voltage regulator. Apparently, if left unchecked (With a disconnected battery, open "ignition" circuit) the output voltage could go to a couple hundred volts which could potentially make the regulator circuitry immolate itself or something to that effect. With the typical setup the diodes burn-out first and prevent catastrophic damage. See here for more details: http://www.pangolin.co.nz/node/16 -Francois Rivard 1990 34+ "Take Five" Lake Lanier, GA Message: 2 Date: Mon, 18 Jul 2016 08:38:01 -0400 From: Dave Syer To: "C&c Stus List" Subject: Stus-List Relocating the Yanmar key now alternator.. Message-ID: Content-Type: text/plain; charset="utf-8" Interesting discussion. So, I have run my 1985 2gm Yanmar briefly with the key removed and no apparent harm was done. The manual does say never to run it with the battery disconnected. Now, when I check the schematic, (and my engine) there is a 30A tubular fuse in series with the key switch. Therefore a blown fuse = an open key switch, and would cause the same damage to the alternator. This does not make a lot of sense to me. Other than adequate knowledge, am I missing something? See below. ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated! ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Stus-List Relocating the Yanmar key now alternator..
Hi Dave, It's possible your alternator is internally wired differently. As for the rest of us (again, what I was told) the diodes are supposedly there meant to both turn the a/c current into dc for use by the batteries and act fuse-like to prevent the possibility some kind of much worse (Overheat / fire perhaps? ) alternator self destruction. All I knew at the time was for 78 bucks and 45 or so minutes of wrenching I could make it all good again and have the peace of mind associated with replacing a 20 year old alternator with a brand new unit. Now that I'm looking into it that appears the catastrophic failure would to be related to the field coils which are energized as the alternator turns and their voltage is regulated by the battery / voltage regulator. Apparently, if left unchecked (With a disconnected battery, open "ignition" circuit) the output voltage could go to a couple hundred volts which could potentially make the regulator circuitry immolate itself or something to that effect. With the typical setup the diodes burn-out first and prevent catastrophic damage. See here for more details: http://www.pangolin.co.nz/node/16 -Francois Rivard 1990 34+ "Take Five" Lake Lanier, GA Message: 2 Date: Mon, 18 Jul 2016 08:38:01 -0400 From: Dave Syer To: "C&c Stus List" Subject: Stus-List Relocating the Yanmar key now alternator.. Message-ID: Content-Type: text/plain; charset="utf-8" Interesting discussion. So, I have run my 1985 2gm Yanmar briefly with the key removed and no apparent harm was done. The manual does say never to run it with the battery disconnected. Now, when I check the schematic, (and my engine) there is a 30A tubular fuse in series with the key switch. Therefore a blown fuse = an open key switch, and would cause the same damage to the alternator. This does not make a lot of sense to me. Other than adequate knowledge, am I missing something? See below. ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Stus-List Relocating the Yanmar key now alternator..
Interesting discussion. So, I have run my 1985 2gm Yanmar briefly with the key removed and no apparent harm was done. The manual does say never to run it with the battery disconnected. Now, when I check the schematic, (and my engine) there is a 30A tubular fuse in series with the key switch. Therefore a blown fuse = an open key switch, and would cause the same damage to the alternator. This does not make a lot of sense to me. Other than adequate knowledge, am I missing something? See below. http://www.cruisersforum.com/forums/members/31207-albums977-picture16384.png Dave Syer - '85 33-2 Message: 1 Date: Sun, 17 Jul 2016 22:47:17 -0400 From: "Jean-Francois J Rivard" To: cnc-list@cnc-list.com Cc: amira...@bellaliant.net Subject: Stus-List Relocating the Yanmar key now alternator.. Message-ID: < of7c4f9827.241c1f14-on00257ff4.000d9ee3-85257ff4.000f5...@notes.na.collabserv.com > Content-Type: text/plain; charset="us-ascii" Agreed, I experienced it 1st hand a few months after I had bought the boat a few years back.. I had a brain fart and turned the key to "off" while the engine was running. The diodes instantly fried, the alternator was toast / the charging warning was light on. ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
Stus-List Relocating the Yanmar key now alternator..
Agreed, I experienced it 1st hand a few months after I had bought the boat a few years back.. I had a brain fart and turned the key to "off" while the engine was running. The diodes instantly fried, the alternator was toast / the charging warning was light on. Then came the alternator saga: (As I was told) Apparently, it's kind of a big deal to replace the diodes. On an older alternator you might as well have the whole alternator rebuilt or buy a new one. I found some original Yanmar alternators but they were $700.00 (I did not know about Mastry Engine center at the time)Upon looking at local rebuild options they were in the $175.00 - 200.00 + range. Upon further research I found an authentic 55 Amp Hitachi (Yanmar's OEM)unit with the exact same connections, mounting, and pulley for 78 bucks shipped on ebay (Still available). That's the one I got. It actually charges the batteries better than the old one.. I guess it was the original and probably due for a rebuild anyway. Francois Rivard 1990 34+ "Take Five" Lake Lanier, GA Message: 5 Date: Sun, 17 Jul 2016 20:39:46 -0300 From: To: Subject: Re: Stus-List Relocating the Yanmar key Message-ID: <9BE1F845BD864E20A70EB87EE8B7BB8A@T60> Content-Type: text/plain; charset="utf-8" Didn?t I read somewhere on this group that it was a bad idea to turn off the key switch while the engine is running? Can someone confirm/deny this? Mike Amirault C&C33ii Lovely Cruise SMSC ___ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!