Alternator upgrade from Catalina direct.

[SV Sand Pebble]

You can also try asking a local alternator shop for an externally regulated marine alternator then use a Balmar Ars-5 (about $275 with harnass) (https://balmar.net/product/regulator-ars-5/) with an alternator temperature sensor (about $40).  Take your old to match the case, pulley and mount.  That'll get you something close to your budget. 

Tell them you want a marine alternator rated for continuous output.  Read Maine Sail's article (https://marinehowto.com/automotive-alternators-vs-deep-cycle-batteries/) to understand what questions to ask.

Years ago I went with a Blue Circle alternator (search Blue Circle here) and have been happy.  Last season I experienced low output so I took it to a local shop.  He rebuilt it for way less than price of a new.

The temperature sensor is important.

You offer another good option. My whole upgrade came to play because when I bought my boat the batteries were old and not matched. When I cha get them a d added a shunt I notice the alternator output was 17 volts, I guess a bad regulator. I disconnected it and for now I have only been day sailing and charging from shore power.

[KWKloeber]

@S/V S

Here is one L-N bulletin on the mod, although Rod's write-up is much clearer/prettier.

Different model, but basically here's what it'll look like under the gasket.  I'm wondering if using a Dremel it could be de-potted so as to provide more working space to bring the two field wires to the outside?   

[SV Sand Pebble]

@S/V S

Here is one L-N bulletin on the mod, although Rod's write-up is much clearer/prettier.

Different model, but basically here's what it'll look like under the gasket.  I'm wondering if using a Dremel it could be de-potted so as to provide more working space to bring the two field wires to the outside?

  Thanks so much for the help and pictures. I ordered the 105 amp unit from Catalina direct today. It's back ordered 4 or 5 weeks. I thought if I can't afford the regulator yet I could run the charging battery through my dc to dc Victron Charger and  at least 3 stage charge my house bank and limit my draw from the house bank to 30 amps maybe keeping the alternator cool enough. Any words of wisdom.

[Stu Jackson]

  Thanks so much for the help and pictures. I ordered the 105 amp unit from Catalina direct today. It's back ordered 4 or 5 weeks. I thought if I can't afford the regulator yet I could run the charging battery through my dc to dc Victron Charger and  at least 3 stage charge my house bank and limit my draw from the house bank to 30 amps maybe keeping the alternator cool enough. Any words of wisdom.

Why bother?  Unless your house bank is horribly depleted, the internal regulator on your old 51A Motorola alternator will get you charging safely. 

How do I know?  Before I installed my 100A alternator and Balmar MC-612, I would cruise with my nominal 400 ah house bank (12V wet cells).  Of course when leaving the dock all charged up, no issue.  But after a night on the hook with the fridge on, the alternator would only be putting out 25A or so.  I knew this because I had an old AutoMac, which I used to improve the output, but could only get it up to 30 or 35A anyway.

Don't complicate things until you get all the rest of your gear installed.

[Catalina007]

  Thanks so much for the help and pictures. I ordered the 105 amp unit from Catalina direct today. It's back ordered 4 or 5 weeks. I thought if I can't afford the regulator yet I could run the charging battery through my dc to dc Victron Charger and  at least 3 stage charge my house bank and limit my draw from the house bank to 30 amps maybe keeping the alternator cool enough. Any words of wisdom.

Why bother?  Unless your house bank is horribly depleted, the internal regulator on your old 51A Motorola alternator will get you charging safely. 

How do I know?  Before I installed my 100A alternator and Balmar MC-612, I would cruise with my nominal 400 ah house bank (12V wet cells).  Of course when leaving the dock all charged up, no issue.  But after a night on the hook with the fridge on, the alternator would only be putting out 25A or so.  I knew this because I had an old AutoMac, which I used to improve the output, but could only get it up to 30 or 35A anyway.

Don't complicate things until you get all the rest of your gear installed.

Unless its Catalina propriety item, I stay away from CD. Thats probably a 100 pct markup on a standard alternator you can get anywhere with no delay.   

[Noah]

007–I think your "stay away from Catalina Direct" is pretty harsh. Yes, many items are higher priced, but not all and some provide a very convenient solution for boats. Also, their customer service is pretty good.

[KWKloeber]

Yes, many items are higher priced, but not all

In this case CD @ $199 appears to be a fair price. 
One of the most-reasonable sources I have used in the past, the L-N 8MR2401U is $262 shipping included; Scamazon $366; ASE $245 + shipping.
I might have mentioned once or twice that I'm not a CD fan about many things, but when it's warranted they should get their due.
Customer service -- from my experience it's 50-50.  I've tried for, maybe 4 years? to get a part number to buy an item they show but don't have a p/n on it.  It's come to be just a game I keep playing just to pass the time on a rainy day.  Like many other places, CD appears to be "front line" employee challenged.


S/V SP:

If time is of the essence, consider a Wilson reman ($170 shipping included.)  Wilson is the largest reman-er in N. America and puts out EXCELLENT products.   I'd rather buy a full reman than a new alt -- you KNOW it is 100% tested and didn't slip by w/ the 99% off the line that don't get tested.

[mainesail]

@S/V S

Here is one L-N bulletin on the mod, although Rod's write-up is much clearer/prettier.

Different model, but basically here's what it'll look like under the gasket.  I'm wondering if using a Dremel it could be de-potted so as to provide more working space to bring the two field wires to the outside?

  Thanks so much for the help and pictures. I ordered the 105 amp unit from Catalina direct today. It's back ordered 4 or 5 weeks. I thought if I can't afford the regulator yet I could run the charging battery through my dc to dc Victron Charger and  at least 3 stage charge my house bank and limit my draw from the house bank to 30 amps maybe keeping the alternator cool enough. Any words of wisdom.

Do Yourself a favor and cancel that order. C/D is selling elcheapo Chinese  clones and they perform horribly. Once you have cancelled the order buy a genuine Leece-Neville from a legit Leece-Neville dealer such as ASE Supply...

[KWKloeber]

Do Yourself a favor and cancel that order. C/D is selling elcheapo Chinese  clones and they perform horribly. Once you have cancelled the order buy a genuine Leece-Neville from a legit Leece-Neville dealer such as ASE Supply...

THOSE SONS OF BIT¢H€$!! 
Displaying a Leece instruction sheet with a knock-off.

Damn, just when you want to try to find some good in a felon, they turn around and try to screw owners again. 

Thank you Rod for passing along that knowledge!!!
Continue your steady uphill climb!!

[SV Sand Pebble]

 
  Thank you all.
  Stu,I was under the impression  that when I enlarged my house bank to 450 amp hours the larger bank if depleted could possibly overheat my old alternator. Even though I'm a industrial electrician I have had up I till lately very little experience with 12 volt systems and batteries. It feels good to begin to put the mystery of boat wiring to rest yet I still have A bit to go. Recently I disconnected my alternator  charge wire and had anew day sails for about 5 hours each. I was surprised even using my wheel autopilot during a ten knot day how little power I actually took from the house bank. Yet if I can hobble along on my old alternator till I have the chance to get both my alternator and external regulator solved great.
  Mainsail, thanks for the heads up on the CD alternator I'm going to cancel Monday morning. A friend with the Catalina 34 next to mine same year 1987 mentioned he seen the 90 amp Leece Neville that may fit our boats on Amazon and he would Send me a link, have not seen the link. I want to be sure it is one that will work. Note: A few here have mentioned that a 90 amp maybe a better option to have mercy on our v-belt.
  So again thank you all.

  On a side note, I took my new stainless steel windless mounting shelf to my boat this weekend, it fit perfect, the back slope for the anchor locker was dead on. I'm sure it will take me to the end of April to finish all my projects, just in time for the season. Wait, what do I mean season, I live in Southern California, its always the season.

  OK, first goal, get the right Lecce Neville Alternator ordered and on its way. I live in the mountains of Southern California and my boats 75 miles away, so although I'm almost there every weekend my projects move forward at a snails pace.

[Jon W]

Regarding having mercy on the v-belt - The Balmar external regulator allows you to monitor alternator and house bank temperature, in addition to having several programmable settings to safely and efficiently get the most out of your charging system. On the MC-614 one of the settings is called belt manager. I've set mine to b-4 and do not have a problem with my v-belts getting eaten up. You can also add the small engine mode feature Stu suggested which is another way to manage v-belt wear. Proper belt tension is also very important.

FWIW - I added the external regulator kit on a L-N 105A that the PO installed prior to 2015. The alternator output connects directly to my 450ah house bank. I also have a 85ah reserve battery charged via a Xantrex Digital Echo Charger.

[SV Sand Pebble]

  Thanks Jon
  All the little bits of advice here helps me to piece together the best plan possible. Stu mentioned the MC-618 that maybe the latest upgrade of the MC-614 from Balmar. I willfind that out when I go to order my regulator. If anyone has a catalog number or links to the Leece Neville 90 or 105 Alternator that would be great, if not I will bang away till I get through all this. I know when I get done with all this I will have an awesome boat.

[Jon W]

I believe the MC-618 is the new version of the MC-614. One nice new feature is that it can connect to your phone with an app for programming or status display.

I attached an old spec sheet for the L-N 105a alternator I have for your reference. It says the L-N 105a alternator is item# 8MR2401UA, sales number 110-567. Noah may have data for the 90a. I'm guessing the L-N 90a sales number may be 110-602.

I don't think the L-N external regulator conversion kit is available anymore, but the PN was 114-307, Kit 1070 as reference if you want to ask around about putting together your own version of it. I bought my kit from ASE Supply.

Just did quick internet search of the PN and I came up with a webste called 2040-parts.com that says it has the conversion kit for $9.99. Don't know anything about the site or if it's still in business. They could still have the kit for sale, or it could be an old add and they don't. If they're in business and don't have it anymore, maybe they could put one together for you. Worth calling and asking.

[SV Sand Pebble]

  Once again Jon, thank you your awesome.
  I do not know how a boat own owner with a modest income! Ado it yourself er who could successful without a site such as this and the good people willing to offer their experience. I love Catalina's for 90 percent of my sailing, I would not mind a Catalina 42 :) I sure wished they has a skeg protected rudder, I'm sure a hydrovane would make me feel better. Anyways I'm off to take the wife out today showing I can do more then sail or talk about sailing. Monday, cancel I'm order with CD, get an order of a new alternator coming and see if I can get that kit for hooking up my regulator. I know there has been a few windless pictures placed here on the site so I plan on sharing mine. It's quite the job yet im feeling really good about the future outcome. Again so much appreciation for all the help from everyone.
  George

[KWKloeber]

S/V SP

I already gave you the model number of the 105a - re-read below.

ASE lists it for more than the the CD knock-off but doesn't indicate if it's in stock (presuming it's truly L-N and n/a scam.)
Wilson lists 3 of the remans in stock (see pic) and NAPA carries Wilson remans but this one may be a special order.) Below is FilterPro's price (+ refundable core charge.)

Look at the L-N model 8MR2349 (sell no. 110-639) for a 90a. It does have external sense terminal, which the 105a does not.

The 8MR2156U 105a has external sense (if you're not going to add an ext reg right away.)

I'm just wondering (if anyone knows?) - if one removes the regulator's B+ wire from the B+ post on the Alt, and instead runs that wire to the battery bank, does that essentially turn the alt into external sense??  (just w/o a screw post on the regulator case.)

You might call Prestolite - 585-492-1700 they're about 15 min from where I used to live (back when there was a "Motorola" sign outside) - nice ppl there.  Tell em you need a drop in replacement for an 8MR2049K alt.

The website has a search for dealers
https://www.prestolite-eu.com/distributors/?utm_source=website-na-btn