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310 Voltage Regulator Location

Nov 18, 2010
2,302
Catalina 310 Hingham, MA
what pushed you to go lithium ion?
We were getting ready to leave St. Thomas to cruise again. Based on capacity tests the LA batteries we had (4 GC) would likely die during this cruising time. And the cost of good quality golf carts in the USVI is around $850. So the cost to go to a similar sized usable bank wasn't too much more. The weight savings it enormous. My whole bank weighs as much as one golf cart. The life cycles should give us many years. And since we had already upgraded our solar and alternator to fully programmable options we didn't have as much of an initial cost jump. Another big factor is the voltage sag. With the lithium I can be at 60% state of charge and run large loads (DC watermaker pulls about 25 amps and the electric kettle pulls 100 amps) and not get into a low voltage situation while they are running.

Eventually I will probably move the bank to a different location and make the space for the batteries tool storage. But that's down the line.

We are 3 months into cruising and love them so far. Sitting on anchor in Martinique. Got up and made coffee (no propane used, just the electric kettle) and started the watermaker. It's only 10 am and my tank is almost full plus I am still putting a couple amps into my bank. By 4 pm I will be back to 100% SOC (which is actually only 90% SOC). It's a great upgrade but not for your average boater. I took over 2 years reading everything I could and still needed advice from people with more knowledge. I also would have these as a weekend boater or liveaboard in a marina. To me they are for cruisers who will put in the work and are on the boat full-time.
 
Nov 16, 2012
873
Catalina 310, 2000, #31 Santa Cruz
And if you ever go to lithium ion batteries in the future then the volt sensing is important. Actually it's important for all battery types but critical for lithium.
Where did you mount the external regulator? Are you using both battery temperature sensors?
 
Nov 18, 2010
2,302
Catalina 310 Hingham, MA
Where did you mount the external regulator? Are you using both battery temperature sensors?
I installed a bumpout behind the exhaust elbow to allow for better cooling. It's in some of my old posts if you want to see it. The regulator is mounted there, on the bulkhead between the engine and the aft berth.

I used had a temp sensor on the old golf cart battery bank when I had it. You don't temp compensate for lithium. I have an alternator temp sensor as well.
 
Mar 16, 2018
20
Catalina 310 202 Aloha Carlyle, IL
Sailing Friends,

It looks like this post took on a life of its own. I wanted to bring closure to the initial issue of the Voltmeter pegging out. Thanks to everyone's advice, I narrowed it down to the Voltmeter itself, and it was indeed bad. Here's a picture of it. Note it's reading 12 Volts and it's not attached to anything. I installed a new Voltmeter and everything works well. Thanks again for all the help.
Voltmeter.jpg
 
Sep 29, 2008
1,766
Catalina 310 #185 Quantico
FWIW, most of the Universal M25XPB's came with a Mando OEM alternator that has an internal regulator. I replaced mine with a Mercruiser one and it was essentially a Mando with the Mercruiser template.

1566264415972.png
 
Feb 6, 1998
11,117
Canadian Sailcraft 36T Casco Bay, ME
Yup. And you can get the Mercruiser ones for about $75 online. They aren't super good quality but they work in a pinch.
Mando has apparently stopped producing marine alternators so any of the "Mando style" alternators are Chinese clones or reman. The Leece-Neville 8MR alternators were better quality and what Westerbeke offered as the optional larger alternators for those engines.
 
Aug 29, 2016
66
Catalina 2004 310 (Hull #250) BC
Here goes to foreign territory...So my mechanic just told me my alternator is dead.

I have a Xantrex externally controlled 105 amp Leece Neville 8MR going to two banks of golf cart Trojan 105T's (I have no idea why 105a vs the stock 55 or otherwise). He says the batteries are fine when load tested, and the controller is good too. I want to have the alternator rebuilt (easily done I"m told) and keep as a spare, but also want to get a Balmar system.
Questions:
1. How do I get the old alternator off? Do I have to worry about the way the wires are disconnected - sequence?
2. I called Balmar - do I have a 1" single foot with universal adjusting ear configuration on the amp based on the pictures?
3. I'm looking at the the 6 series 100 amp model. Does anyone know if it will fit? What model and setup configuration for the amp/belt manager would I specify when I order? (Will also get the MC-614 regulator).
4. Will probably get the Balmar Smartgauge battery monitor too because...I don't have one and it's just more money to throw at the issue, right?
 

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Last edited:
May 20, 2016
2,883
Catalina 36 MK1 94 Everett, WA
First disconnect the batteries. You will have several wires going to your alternator
1) alternator output (B,B+) treat this wire as hot when batteries are connected
2) Field - adjusts the alternator output (F)
3) tach or AC out (S,T,P)
4) ground (G)
5) idiot light (may not be present) (L,I)

Be sure and mark the wires as to function and with the letter next to the mounting bolts. Double check there is no voltage to ground on all wires before starting to removing anything!!!!!!

I like to wrap the alternator out and field wires with tape Incase the batteries get magically connected.

A) remove the bolt on the adjuster arm at the alternator and loosen the bolt at the other end
B) remove long bolt and nut on the alternator pivot point.

Removal complete. Assemble in reverse order, Along with the spool extension on the new alternator you may need a thin sleeve to bush out the pivot bolt - if the bolt wabbles in the hole you most likely need the sleeve.

Letters on new alternator may not match the old. You can google what the mean and match to the function. Letters in parens above are common letters used for this wire.

Easy 1 hr job.

Problem areas. Mount holes for the adjustment bracket are not all consistent, you may need a new mounting arm or rework the existing one.

Les
 
Last edited:
Nov 18, 2010
2,302
Catalina 310 Hingham, MA
Some thoughts to add to above.

First, why Balmar? Mainesail makes his own over at Marinehowto.com that will match your existing alternator almost exactly. I have the 105 amp. I got my MC-614 regulator from him as well.

Second, is that the external regulator mounted in the engine area? If so you should consider moving it while you do the change over.

Third, from what I can see your wire for the alternator output looks significantly undersized. Some more pictures of the wire and understanding how it is run would be helpful. You might also want to consider a service disconnect as an upgrade while you are doing this work.

Lastly, go to Marine How To and read everything Mainesail has there on alternators and regulators before you start. There is a lot of helpful information there. For instance, it appears you are just case grounding the alternator. You can improve performance with a ground wire connected to the grounding buss or point.

On a side note, your coolant overflow is plumbed a little strange. Is it actually working like that? Do you see the coolant level rise and fall as you operate the engine?

Good luck and fair winds,

Jesse
 
Feb 6, 1998
11,117
Canadian Sailcraft 36T Casco Bay, ME
Here goes to foreign territory...So my mechanic just told me my alternator is dead.

I have a Xantrex externally controlled 105 amp Leece Neville 8MR going to two banks of golf cart Trojan 105T's (I have no idea why 105a vs the stock 55 or otherwise). He says the batteries are fine when load tested, and the controller is good too. I want to have the alternator rebuilt (easily done I"m told) and keep as a spare, but also want to get a Balmar system.
Questions:
1. How do I get the old alternator off? Do I have to worry about the way the wires are disconnected - sequence?
2. I called Balmar - do I have a 1" single foot with universal adjusting ear configuration on the amp based on the pictures?
3. I'm looking at the the 6 series 100 amp model. Does anyone know if it will fit? What model and setup configuration for the amp/belt manager would I specify when I order? (Will also get the MC-614 regulator).
4. Will probably get the Balmar Smartgauge battery monitor too because...I don't have one and it's just more money to throw at the issue, right?

A few thoughts.

#1 Unless you upgrade to a serpentine/multi-rib belt your alternator, being driven by a 3/8" or 10mm belt (with marginal wrap), should be limited to about 65-70A or so max. With "perfect" belt wrap a 3/8" belt can do 80A for a short time. With minimal belt wrap 60-70A is about the max.. If your regulator can not do this, and only the Xantrex XAR (made by Balmar) could, then the regulator is a major part of the problem.

This article goes into great detail on alternator installation: Alternator Installation Tips & Tricks

#2 The heat developed in the pulley, due to slippage, is directly transferred into the alternator. If the alternator was not "current limited" this level of heat can be quite a bit more work for the alternator to cool.

#3 Cheap stamped steel pulleys do not do well with high heat and tend to "expand" and loosen the belt further when hot. Billet machined steel pulleys do much better in this regard. 8MR 5/8" ID billet machined pulleys can be found here: 8MR Billet Machined 5/8" ID X 3/8" Belt Pulley

#4 There is something odd about the photo of the external regulation plate? The negative of one brush must ground to the B- stud. This is done externally because the pictured alternator is an isolated ground model. If someone grounded that second brush inside the regulation plate, to the frame of the alt, for clearance purposes, it won't work. There is no path to the neg rectifier, if this was done, because it is isolated from the frame. I don't see the second negative brush stud on the regulator conversion plate.....?

#5 What gauge are the B+ (+ alt output) and B- (negative alternator output) wires? These wires should ideally be sized for 2% max voltage drop but 3% can suffice.

#6 You have a 1" foot 8MR with a 2" fit kit installed.. Your engine accepts a 2" foot alternator. Be very careful with that Universal foot mount bracket as they are typically made of cheap machined cast aluminum. A fair number of them have snapped. Make sure there is NO SLOP when you tighten the pivot bolt. If there is any slop a spacer will need to be inserted so the alternator foot is a snug fit..

#7 If buying a Balmar, not really necessary here, the 120A is our favorite model. This alternator would need a very deep belt load manager setting to run on a 3/8" belt. Buying a 120A now would set you up for better performance down the road, should you decide to go with a serpentine kit.

#8 The difference between the 8MR 105A and the 6-Series 100A will not really be evident as you are limited by the belt and both alternators will happily run at 65-70A (current is limited via Belt Load Manager).

#9 Yes the dual internal fans of the 6-Series do cool better, and it has a heavier rectifier than the 8MR2401, but unless you have the ability to push either of these alternator to their limits (serpentine kit) there will be little added value going to the 6-Series.

#10 Balmar regulators are programmed at the installer level. There is almost no end to what you can program in the MC-614H. I would however strongly advise at least an alternator temp sensor whether you go with a 6-Series or rebuild the 8MR. A battery temp sensor is also a wise investment.

This alternator covers programming a Balmar Regulator:Programming a Balmar External Voltage Regulator
 
  • Like
Likes: BC Bernie
Aug 29, 2016
66
Catalina 2004 310 (Hull #250) BC
Some thoughts to add to above.

First, why Balmar? Mainesail makes his own over at Marinehowto.com that will match your existing alternator almost exactly. I have the 105 amp. I got my MC-614 regulator from him as well.

Second, is that the external regulator mounted in the engine area? If so you should consider moving it while you do the change over.

Third, from what I can see your wire for the alternator output looks significantly undersized. Some more pictures of the wire and understanding how it is run would be helpful. You might also want to consider a service disconnect as an upgrade while you are doing this work.

Lastly, go to Marine How To and read everything Mainesail has there on alternators and regulators before you start. There is a lot of helpful information there. For instance, it appears you are just case grounding the alternator. You can improve performance with a ground wire connected to the grounding buss or point.

On a side note, your coolant overflow is plumbed a little strange. Is it actually working like that? Do you see the coolant level rise and fall as you operate the engine?

Good luck and fair winds,

Jesse
Well here's some politics you've probably heard before: I've been putting off this project for two years now and I really want to support Mainsail products, (especially as you have both already pointed out in previous posts his parts are so well made and fitted) but I already know that I will hire out some of the local Canadian professionals to help me, and they have specified in no uncertain terms that they will only use products that are sourced out from certain manufacturers (like Balmar), in order to satisfy the insurance company (...ok the can of worms has been opened).

As you have noticed, the previous owner has done some funky wiring and an upgrade in the layout is in order, such as relocation of the controller, and possible service disconnect upgrade. I'm quite wary of anything electrical and although it's great to save a buck here and there and to try to do it all oneself (which is fun and satisfying) , the repercussions of a poor install by me probably justifies paying out a pro, if not just for the question of liability. Once the new system is re-established, I would definitely use Mainesail's parts as future swap switchouts.

About the coolant - funny you mention that because that is my next systems project...and no the level never changes during engine use...why is that?? Again, a systems review always triggers a domino effect - eg. I want to switch out the heat exchanger too and have it pressure tested at the radiator shop. So much learning going on.

Thank you so much for your input.
 
Last edited:
Aug 29, 2016
66
Catalina 2004 310 (Hull #250) BC
A few thoughts.

#1 Unless you upgrade to a serpentine/multi-rib belt your alternator, being driven by a 3/8" or 10mm belt (with marginal wrap), should be limited to about 65-70A or so max. With "perfect" belt wrap a 3/8" belt can do 80A for a short time. With minimal belt wrap 60-70A is about the max.. If your regulator can not do this, and only the Xantrex XAR (made by Balmar) could, then the regulator is a major part of the problem.

This article goes into great detail on alternator installation: Alternator Installation Tips & Tricks

#2 The heat developed in the pulley, due to slippage, is directly transferred into the alternator. If the alternator was not "current limited" this level of heat can be quite a bit more work for the alternator to cool.

#3 Cheap stamped steel pulleys do not do well with high heat and tend to "expand" and loosen the belt further when hot. Billet machined steel pulleys do much better in this regard. 8MR 5/8" ID billet machined pulleys can be found here: 8MR Billet Machined 5/8" ID X 3/8" Belt Pulley

#4 There is something odd about the photo of the external regulation plate? The negative of one brush must ground to the B- stud. This is done externally because the pictured alternator is an isolated ground model. If someone grounded that second brush inside the regulation plate, to the frame of the alt, for clearance purposes, it won't work. There is no path to the neg rectifier, if this was done, because it is isolated from the frame. I don't see the second negative brush stud on the regulator conversion plate.....?

#5 What gauge are the B+ (+ alt output) and B- (negative alternator output) wires? These wires should ideally be sized for 2% max voltage drop but 3% can suffice.

#6 You have a 1" foot 8MR with a 2" fit kit installed.. Your engine accepts a 2" foot alternator. Be very careful with that Universal foot mount bracket as they are typically made of cheap machined cast aluminum. A fair number of them have snapped. Make sure there is NO SLOP when you tighten the pivot bolt. If there is any slop a spacer will need to be inserted so the alternator foot is a snug fit..

#7 If buying a Balmar, not really necessary here, the 120A is our favorite model. This alternator would need a very deep belt load manager setting to run on a 3/8" belt. Buying a 120A now would set you up for better performance down the road, should you decide to go with a serpentine kit.

#8 The difference between the 8MR 105A and the 6-Series 100A will not really be evident as you are limited by the belt and both alternators will happily run at 65-70A (current is limited via Belt Load Manager).

#9 Yes the dual internal fans of the 6-Series do cool better, and it has a heavier rectifier than the 8MR2401, but unless you have the ability to push either of these alternator to their limits (serpentine kit) there will be little added value going to the 6-Series.

#10 Balmar regulators are programmed at the installer level. There is almost no end to what you can program in the MC-614H. I would however strongly advise at least an alternator temp sensor whether you go with a 6-Series or rebuild the 8MR. A battery temp sensor is also a wise investment.

This alternator covers programming a Balmar Regulator:Programming a Balmar External Voltage Regulator
First of all, thank you so much for your knowledgeable input. Your generosity and willingness to share your expertise is legendary.

An opportunity exists to improve the present layout and plan a better system. I'll have to do another review of the future 24 hr amp demands of my boat to match the system.
 
Nov 18, 2010
2,302
Catalina 310 Hingham, MA
I'll have to do another review of the future 24 hr amp demands of my boat to match the system.
Obviously some equipment on your boat will differ but without my watermaker we use about 125-150 amp hours per day. This is with 3 fans running almost non-stop and all lights on LED including the anchor light that we don't even bother shutting off during the day since the LED uses virtually nothing. This includes the fridge that runs 24/7 and a laptop that is on and plug in for 12 volt for close to 12 hours a day (used for music, TV, internet, etc.). We will typically wake up down 85-120 Ah after being fully charged when the sun stops giving juice around 4:30.

Our solar, 495 watts, covers that plus our watermaker on typical days.

Good luck,

Jesse
 
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Likes: BC Bernie
Nov 18, 2010
2,302
Catalina 310 Hingham, MA
About the coolant - funny you mention that because that is my next systems project...and no the level never changes during engine use...why is that?? Again, a systems review always triggers a domino effect - eg. I want to switch out the heat exchanger too and have it pressure tested at the radiator shop. So much learning going on.

Thank you so much for your input.
There was a thread a couple of weeks ago about the hole going from the overflow tank to the manifold. Start there as the hole is likely blocked. Then correct the angle and hose setup when you put it back together. Right now the hose goes down and then back up. I would suspect this reduces flow as opposed to going in a straight line.

The heat exchanger is a good idea. You will likely find some broken brackets. Mr. Cool makes a better bracket than the westerbeke ones. Let me know if you needa link.

Good luck and fair winds,

Jesse
 
  • Like
Likes: BC Bernie
Oct 22, 2014
11,359
CAL 35 Cruiser Portland OR, moored EVERETT WA
local Canadian professionals to help me, and they have specified in no uncertain terms that they will only use products that are sourced out from certain manufacturers
Bernie. I understand your statements and that of professionals that have accepted a degree of liability for the products they use and install on your boat.

That being said, they did not come to their decisions with out study. And before Balmar was the company they are there were other manufactures being used. Perhaps this is a time that you could explore with the "Pro" the information and capabilities of the products MaineSail has developed and provided for sale.

It is also possible that the Pro has a sourced price structure and specific training on install. Thus limiting their willingness to change. Totally understandable from a production sense.

Change is a bitch..

Not being a Marine Electrical Professional, but having an inquisitive mind... I did research the Balmar products and they are of a high quality (the plant was in my boats back yard, Marysville, WA) before they were bought and moved to what Alabama. I looked into the products of MaineSail as well as the Electrical shops in Everett and my home in Salem OR. I listened to the owners electrical expertise and watched their production work/testing on alternators. With all that as background I elected to get supplied by MaineSail and after working with him I happily endorse his product and support.

I share this not expecting it to have any impact on your immediate situation, but perhaps help your Pro should their resource with Balmar become clogged, they might find the products offered by MaineSail a great alternative.

Hope to see you sometime out on the waters of the Salish Sea.
 
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Likes: BC Bernie
Aug 29, 2016
66
Catalina 2004 310 (Hull #250) BC
Maine Sail, post:
"#6 You have a 1" foot 8MR with a 2" fit kit installed.. Your engine accepts a 2" foot alternator. Be very careful with that Universal foot mount bracket as they are typically made of cheap machined cast aluminum. A fair number of them have snapped."

Sure enough, this is a pic of what was found when my old alternator was taken off...Suggestions anyone?
 

Attachments

Last edited:
Feb 6, 1998
11,117
Canadian Sailcraft 36T Casco Bay, ME
Take the old bracket to a machine shop and have them duplicate it in billet steel. I think I have a customer who did this and I remember vaguely that he may have made a second one.

I think Westerbeke is still shipping them in aluminum, but try to contact them and check. Perhaps they have corrected the issue and gone back to steel brackets??
 
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  • Like
Likes: BC Bernie
Aug 29, 2016
66
Catalina 2004 310 (Hull #250) BC
Has anyone installed this retro fit kit, that addresses the propensity for the weak aluminum alternator bracket to break?