I had posted a few months back about replacing my alternator on a 89 Cat 30 with a Universal M25XP engine. I did purchase locally a 72 amp Leece-Neville marine alternator, and had the shop modify it for external regulation. I also purchased a Balmar MC-612-H Max Charge regulator. Now that the skis are stored, and my trip to the BVI's is booked for April 08, it is now time to start thinking about how to install these two items. When I pulled the original alternator (Motorola 51 amp) I noted only 4 wires. There was a black, which I find strange that was connected to the + pos output, an A.C. Tap and two additional wires which are not marked on the back of the alternator. I would guess that one is the Sense and the other the exciter. The new alternator has the following: Ground, Field, Batt Pos and Aux. Where do I start? I have not even gotten to the Balmar Regulator. I need help, or I will be at the mercy of my yard. I pride myself on doing my own work, but this time I might have gotten in over my head. Any help would be appreciated.One other question; I cannot gain enough clearance in front of the engine to remove and replace the alternator belt. The only way to get the belt off seems to be to cut a notch in the fiberglass under the engine access panel.
Alternator Replacement
- Thread starter chief14326
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Here's someone else who did it
http://www.pbase.com/mainecruising/catalina_36_alternator I think you can contact him through his website - perhaps he could help?
http://www.pbase.com/mainecruising/catalina_36_alternator I think you can contact him through his website - perhaps he could help?
Naming things
Positive - pretty simple it goes to the starter + terminal which then goes to the battery + terminal Negative - also simple it goes to the engine ground via a 72 amp capable cable BTW. There can be some confusion here as some OEM products have a "body" ground that uses the alternator case to mounting bracket to engine block to engine block ground as the "ground" circuit for the alternator. Any alternator with a negative terminal has to be grounded by a wire to the engine ground. The case of the alternator will not carry current on these types Field - this is the wire that comes from the brushes. Its other end is internally (if only one terminal) or externally (it two terminals) attached to the bat neg and by applying voltage to it you "full field" the rotor windings making the alternator stator windings react to the now very strong magnetic field in the rotor and resulting in the maximum production of electricity (if you turn the alternator fast enough that is). This is not a high current circuit as all it dose is cause a magnetic field to be produced in the rotor. This is the wire(s) that get attached to the regulator for output control of the alternator. The reg will most likley also call these "field" wires Aux - not a standard gasoline alternator thing and unique to the diesel alternator. It allows you access to the AC voltage of the stator windings from which a diesel tachometer can deduce RPM. If you want a wiring diagram email me at roosaw@verizon.net and I'll gin one up for you.
Positive - pretty simple it goes to the starter + terminal which then goes to the battery + terminal Negative - also simple it goes to the engine ground via a 72 amp capable cable BTW. There can be some confusion here as some OEM products have a "body" ground that uses the alternator case to mounting bracket to engine block to engine block ground as the "ground" circuit for the alternator. Any alternator with a negative terminal has to be grounded by a wire to the engine ground. The case of the alternator will not carry current on these types Field - this is the wire that comes from the brushes. Its other end is internally (if only one terminal) or externally (it two terminals) attached to the bat neg and by applying voltage to it you "full field" the rotor windings making the alternator stator windings react to the now very strong magnetic field in the rotor and resulting in the maximum production of electricity (if you turn the alternator fast enough that is). This is not a high current circuit as all it dose is cause a magnetic field to be produced in the rotor. This is the wire(s) that get attached to the regulator for output control of the alternator. The reg will most likley also call these "field" wires Aux - not a standard gasoline alternator thing and unique to the diesel alternator. It allows you access to the AC voltage of the stator windings from which a diesel tachometer can deduce RPM. If you want a wiring diagram email me at roosaw@verizon.net and I'll gin one up for you.
That link below is my article..
That link referenced below is my article: http://www.pbase.com/mainecruising/catalina_36_alternator and I've done that same installation two times on two different Catalina's. On my current boat I did NOT use an external regulator as I found very little difference in charging performance between the so called "dumb" regulator and the so called "smart regulator". Actually I did start out using a Balmar regulator, but after it failed (this is the second Balmar regulator I've had fail), I temporarily installed the "dumb" regulator and found virtually NO difference. After comparing the data I decided to sell the ARS-5 after I got the replacement. Both the ARS-4 and the ARS-5 failed similarly with an intermittent circuit board break. You could wiggle the wiring harness and get it to fire up but it would then shut down again. If you have not already ordered the "smart regulator" you can run the Leece-Neville with it's built in regulator just fine. My data, for my decision not to use a smart regulator, was based on actual output at different rates of discharge using both the "dumb" regulator and the "smart" regulator as measured by a Xantrex XBM. At a 50% discharge the "smart regulator" shaved off about 10 minutes of time getting the batteries back to 90% but from 90% on up the rate of charge, output voltage and time to 100% is virtually identical. After doing my comparisons I really find it hard to justify another $300.00 to save 10 minutes...
That link referenced below is my article: http://www.pbase.com/mainecruising/catalina_36_alternator and I've done that same installation two times on two different Catalina's. On my current boat I did NOT use an external regulator as I found very little difference in charging performance between the so called "dumb" regulator and the so called "smart regulator". Actually I did start out using a Balmar regulator, but after it failed (this is the second Balmar regulator I've had fail), I temporarily installed the "dumb" regulator and found virtually NO difference. After comparing the data I decided to sell the ARS-5 after I got the replacement. Both the ARS-4 and the ARS-5 failed similarly with an intermittent circuit board break. You could wiggle the wiring harness and get it to fire up but it would then shut down again. If you have not already ordered the "smart regulator" you can run the Leece-Neville with it's built in regulator just fine. My data, for my decision not to use a smart regulator, was based on actual output at different rates of discharge using both the "dumb" regulator and the "smart" regulator as measured by a Xantrex XBM. At a 50% discharge the "smart regulator" shaved off about 10 minutes of time getting the batteries back to 90% but from 90% on up the rate of charge, output voltage and time to 100% is virtually identical. After doing my comparisons I really find it hard to justify another $300.00 to save 10 minutes...
Great website
You have a terrific website, and some great other projects. Any chance I could contact you directly? My e mail address is as follows: jaffew@welchallyn.com Thanks
You have a terrific website, and some great other projects. Any chance I could contact you directly? My e mail address is as follows: jaffew@welchallyn.com Thanks
Better than a wiring diagram *
Sometimes...it can be better to take a picture with a digital camera of a pre-project item. It gives the best reflection of how things were.
Sometimes...it can be better to take a picture with a digital camera of a pre-project item. It gives the best reflection of how things were.
Dumb Regulator
MainSail, I too appreciate all the detail and especially the subsequent testing. It sure saves a lot of money to go with the "dumb" regulator if it really does not make a difference. When you say a "dumb" regulator were you using the one mounted internally, so to speak, on your 100amp new alternator or was it another "dumb" regulator mounted on an external mount that you discussed on your website. Thanks Good Winds Dave M s/v DAMWEGAS
MainSail, I too appreciate all the detail and especially the subsequent testing. It sure saves a lot of money to go with the "dumb" regulator if it really does not make a difference. When you say a "dumb" regulator were you using the one mounted internally, so to speak, on your 100amp new alternator or was it another "dumb" regulator mounted on an external mount that you discussed on your website. Thanks Good Winds Dave M s/v DAMWEGAS
Not so "dumb" after all
The key important critical most basic you-get-the-idea is the adjustable voltage output on the LN regulator. Most "dumb" regulators will only put out 13.8 V which will eventually chronically undercharge your batteries. Maine Sail's efforts and detective work are valuable, just don't think that all "dumb" regulators are created equal. They're not.
The key important critical most basic you-get-the-idea is the adjustable voltage output on the LN regulator. Most "dumb" regulators will only put out 13.8 V which will eventually chronically undercharge your batteries. Maine Sail's efforts and detective work are valuable, just don't think that all "dumb" regulators are created equal. They're not.
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