New or rebuilt alternators?

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Seevee

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430 Mainship
Looking for advice.
Currently have two 80a regulated Hatchi alternators on my Mainship and need them unregulated to use an external regulator. What are the goods/bads on having them rebuilt vs. just buying new. New ones are pricey... Balmar's replacement is $688.
Also, anyone know a top notch alternator rebuilder in the Tampa Bay area? or anywhere for that matter... just need the best.
 
I got this done on two 115 amg alternators on my cummins. Cost about $100 to unregulated them. Took the shop about 15 minutes total time.
 
The 80A Hitachi alternators are relatively low amperage units. Replacement 100A alternators from Balmar are lots more expensive, but include better fan cooling, heavier windings and stronger diodes.

Modifying a Hitachi alternator to work with an external regulator just ups the charging current with no way to remove the additional heat. They may not last long.

I would go with the Balmar alternators. Expensive, yes but they work.

Oh yes, others will say go with a Leece Neville alternator that will be much cheaper. Yes it will but it won't match the Hitachi engine mounts.

David
 
The 80A Hitachi alternators are relatively low amperage units. Replacement 100A alternators from Balmar are lots more expensive, but include better fan cooling, heavier windings and stronger diodes.

Modifying a Hitachi alternator to work with an external regulator just ups the charging current with no way to remove the additional heat. They may not last long.

I would go with the Balmar alternators. Expensive, yes but they work.

Oh yes, others will say go with a Leece Neville alternator that will be much cheaper. Yes it will but it won't match the Hitachi engine mounts.

David


Dave,


I have no problem going with the Balmars, but why would heat be an issue by rebuildling the 80a Hatchis? They will still be 80a and they cool fine now.


Besides, two 80s are more than I need.
 
Dave,


I have no problem going with the Balmars, but why would heat be an issue by rebuildling the 80a Hatchis? They will still be 80a and they cool fine now.


Besides, two 80s are more than I need.
It is typical for an internally regulated alternator to spend little time at a high amp
charging output.
They are mainly intended to replace the charge lost by engine starting and minor
accessory use. It is unlikely it would ever put out its maximum 80 amp rating at all.

By changing to external regulation the alternator can be run at maximum output
for as long as the regulator demands. This can overheat a standard duty alternator.

On my last boat I upgraded to a heavy duty small frame 100 amp alternator and a
programmable external regulator. I kept the old alternator for a spare. ;)
 
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Our little Delco alternator is rated at 65A and I've never seen it output more than 45. It'll bring up our small 300A house bank easily after a few hours after being on the hook for a day or 2. It gets pretty warm but what the heck. I thought about upgrading to a Balmar but by the time I buy a balmar and a programmable regulator, I could've easily bought 6 or 7 new Delcos. Since they seem to last us a minimum of 3-5 years and I can swap it in about 5 minutes, for now I'm ok with just keeping a spare onboard.
 
Good timing on this thread. I'm planning to replace my alternators in the spring. Marine Power 454's with stock/original 50 amp alternators. Double pulley wheels already, so that's nice. I was thinking of upgrading to Balmars myself too but yikes those things are expensive. Both voltmeters currently show about 12.5 volts both engines, a little too low, with brand new batteries both sides and spanking clean cable contacts and new 50 amp fuse boxes and a new solenoid just for kicks, so I don't think it's a battery or cable issue. Since the alternators are likely original (1996) it's probably time for new ones anyway (695 hours on the engines). Since I have to do everything myself and I'd like to keep it as simple as possible, I'm thinking of just upgrading to Delco 70 amp, or something like that. Relatively easy swap and because I'm no pro with electricity, I'm reluctant to get into installing external regulators. We're not poverty stricken and as boat expenses go Balmars won't break the bank, it just seems hard to justify that double or triple expense, especially if the stock 50 amp'ers lasted 25 years.
 
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Our little Delco alternator is rated at 65A and I've never seen it output more than 45. It'll bring up our small 300A house bank easily after a few hours after being on the hook for a day or 2. It gets pretty warm but what the heck. I thought about upgrading to a Balmar but by the time I buy a balmar and a programmable regulator, I could've easily bought 6 or 7 new Delcos. Since they seem to last us a minimum of 3-5 years and I can swap it in about 5 minutes, for now I'm ok with just keeping a spare onboard.




Three to five years is HORRIBLE! I just don't want to deal with that and would be glad to pay the price for quality. I've never had an alternator fail on a boat or plane. I get the best, keep them maintained and rely on them. The alternators on my plane are over 40 years old, but get rebuilt every 500 hours.
 
Three to five years is HORRIBLE! I just don't want to deal with that and would be glad to pay the price for quality. I've never had an alternator fail on a boat or plane. I get the best, keep them maintained and rely on them. The alternators on my plane are over 40 years old, but get rebuilt every 500 hours.

Haha it might seem so but I get 500 hours out of an alternator and instead of rebuilding it, I replace it with a new $150 one and we're good for another 500 hours. That sounds a little less horrible. :D
Remember, we have an old ,inexpensive Mainship. Not a big new shiny one like you!
 
It is typical for an internally regulated alternator to spend little time at a high amp
charging output.
They are mainly intended to replace the charge lost by engine starting and minor
accessory use. It is unlikely it would ever put out its maximum 80 amp rating at all.

By changing to external regulation the alternator can be run at maximum output
for as long as the regulator demands. This can overheat a standard duty alternator.

On my last boat I upgraded to a heavy duty small frame 100 amp alternator and a
programmable external regulator. I kept the old alternator for a spare. ;)

:thumb: What he said.

David
 
I wouldn't have upgraded my alternator if the only choice was Balmar products.
Their quality is very high but I couldn't have justified their prices at that time.
I went with less expensive components from two different manufacturers.

In that spirit I'm posting this link to the ZRD company: www.zrd.com

I realize that at around $600 it still isn't cheap.
20 years ago I paid about $250 for something similar.
I bought an external regulator at a boat show for about $250 as well.

Time moves on and at least ZRD takes a lot of the guesswork out of upgrading
with their engine-matched package deal approach.
SeeVee, it may help that they are in Titusville, FL.
 
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I use a large frame 220 amp Leece Neville commercial alternator with a Balmar external regulator for charging my house bank. Contrary to someone who hasn't posted yet, you can't buy these inexpensively. They have large bearing, an oversized fan and put out rated capacity continuously. The setup in the link cost over a thousand dollars 7 years ago, not counting any labor. It now has 3,500 hours on it. A close examination of Balmar's large frame high output alternators leads me to believe they are made by Leece Neville / Prestolite.

https://www.trawlerforum.com/forums/members/1458-albums983.html

Ted
 
I use a large frame 220 amp Leece Neville commercial alternator with a Balmar external regulator for charging my house bank. Contrary to someone who hasn't posted yet, you can't buy these inexpensively. They have large bearing, an oversized fan and put out rated capacity continuously. The setup in the link cost over a thousand dollars 7 years ago, not counting any labor. It now has 3,500 hours on it. A close examination of Balmar's large frame high output alternators leads me to believe they are made by Leece Neville / Prestolite.

https://www.trawlerforum.com/forums/members/1458-albums983.html

Ted


Good info.... this stuff IS expensive, and the 100a Balmar is $660 or so, plus the regulators and Centerfielder (combines them) making the price tag for two engine in the $2500 bracket, plus labor. However, that would be a quality choice.



The only thing I'm considering is rebuilding my current alternator and converting them to a non regulating alternator.



I've heard pros and cons both ways.



FWIW... the 80s are more than adequate for my needs.
 
Generally you can’t run the stock alternators at the rated output without having them burn up. I agree that they will not cool well enough. Even some of the high output alternators won’t run at the rated output without some forced air cooling. The reason stock alternators run for years is that they never come close to rated output and if they did it would be for a brief time. Get a quality high output alternator and an external regulator. Then you will be good. It won’t be cheap but it will work well. I got a 120 amp Balmar with a regulator from Defender First for less than one boat unit. I did one engine with the high output and had it charge the house bank only. The other engine had the stock alternator and charged both start batteries through an ACR.
 
I use GM CS-144 alternators because they're easy plentiful. They run from $50 to $500 with amp outputs from 140 to 300 on ebay. With an external regulator that measures alternator temp, they should last a long time. If you're handy, it's easy to replace the internal parts.
I've been using them for 10 years on my current boat and none has failed. Including a couple I setup to output 48v.
 
"The only thing I'm considering is rebuilding my current alternator and converting them to a non regulating alternator."

If by non regulated you mean to disconnect the internal V regulator and replace it with an external reg suitable for charging that is a good idea.

At full output it is questionable how long it will live , but of you install a V reg that senses the alt temperature it should live long and prosper.

The cost difference between a "marine" alt like a Balmar and a Leece Neville 135A truck unit should easily cover the cost of a new mounting bracket, and belt?
 
I had an 80 amp Balmar and their regulator on my Albin. I never saw more than 45 amps but I was only running at 1700 rpm.
That was way more than adequate charging my battery banks when we did our summer cruises in Canada, even with many days without shore power.
I did have the temp probe for the Alternator and the output backed off 20%.

I think that if you set up the regulators wisely your stock alternators should be ok.
 
Looking for advice.
Currently have two 80a regulated Hatchi alternators on my Mainship and need them unregulated to use an external regulator. What are the goods/bads on having them rebuilt vs. just buying new. New ones are pricey... Balmar's replacement is $688.
Also, anyone know a top notch alternator rebuilder in the Tampa Bay area? or anywhere for that matter... just need the best.
Read the extensive articles to be found on Rod Collins' marinehowto.com website. He recently became very ill and is off-line but his website is still up. Tons of good info there. Heed DavidM's advice in Post #3. Converting may work but only if your system does not have a high demand. If you have a large bank you risk burning up those Hitachis in short order.
 
I had an 80 amp Balmar and their regulator on my Albin. I never saw more than 45 amps but I was only running at 1700 rpm.

That was way more than adequate charging my battery banks when we did our summer cruises in Canada, even with many days without shore power.

I did have the temp probe for the Alternator and the output backed off 20%.



I think that if you set up the regulators wisely your stock alternators should be ok.
With respect to jleonard, saying that, set up properly, the Hitachis should be okay is incomplete advice at best without knowing the size of the battery bank to be charged and to what level of discharge the bank would ordinarily go. It might be helpful to have jleonard's opinion on what a "properly set up system" would look like.

By the way, Balmar's 70-amp and 100-amp Series 6 alternators reach their peak output at about 3,000 RPM. Remember, most pulleys on alternators are two-to-one so the Balmar on that Albin was putting out at max level at 1,700 RPM engine speed. The Balmar 70-amp version puts out 77 amps when cold and 65 amps when hot. The 100-amp version puts out 106 and 93. Cold is 78F and hot is 194F. I could not find an 80-amp Balmar currently on their website.

My 100-amp versions max out at 70-amps as measured at startup with a significant load and measured with a high-quality Fluke clamp meter. There are many factors that affect output including the gauge of the output wire to the batteries. Also, if the output wire is run through the starter cable rather than directly to the batteries, the regulators may be getting less than optimal information to regulate.

One thing I think is certain. Never assume that your alternators are producing at their nominal levels. The only certain way is to use a clamp-on meter placed on the output wire leading from the alternator with a significant draw on the system and measured at engine startup. Unless changed, the Balmar regulator goes into bulk charge for 18 minutes at startup although this can be reduced to as little as six minutes. If internally regulated, it won't matter. With a big load on that internally-regulated alternator will go to max output almost immediately and stay there.

Jleonard, no doubt your Albin setup was more than adequate for your boat. It wouldn't be anywhere close to adequate for my use case. Every boat is different. For example, I mentioned earlier that my two 100-amp Balmars put out 70 amps each. My Magnum 2812 inverter/charger charges to a max of 125 amps so, when cruising, my batteries can potentially be charged more quickly than when plugged into shore power. My house bank (no seprate starting batteries) is flooded 932 ah (nominal) and we generally deplete to 50%. It takes about 5.5 to 6 hours for a full recharge.
 
Read the extensive articles to be found on Rod Collins' marinehowto.com website. He recently became very ill and is off-line but his website is still up. Tons of good info there. Heed DavidM's advice in Post #3. Converting may work but only if your system does not have a high demand. If you have a large bank you risk burning up those Hitachis in short order.


Excellent advise, and I've been there. I've bought a ton of stuff from him and hope to buy more.

Any word on how he's doing? Hope he recovers well and stays healthy. Great guy. I send him and email and didn't get a reply.
 
I use a large frame 220 amp Leece Neville commercial alternator with a Balmar external regulator for charging my house bank. Contrary to someone who hasn't posted yet, you can't buy these inexpensively. They have large bearing, an oversized fan and put out rated capacity continuously. The setup in the link cost over a thousand dollars 7 years ago, not counting any labor. It now has 3,500 hours on it. A close examination of Balmar's large frame high output alternators leads me to believe they are made by Leece Neville / Prestolite.



https://www.trawlerforum.com/forums/members/1458-albums983.html



Ted
Ted, I would choose as you have if I could have a do-over. I have Lehman 120s each with a Balmar 100-amp Series 6 alternator. Of course, I also needed a Centerfielder to control them both. One of my Lehmans is already double-belted. My Balmars each put out a max of 70 amps. Your Leece-Neville puts out over 200 amps assuming you are measuring the output wire. In any case, no Centerfielder needed. If I were to have done the Leece-Neville, the second engine could be equipped with a dumb alternator to charge my generator batteries. Simple, effective, and perhaps less expensive overall that the full-monty Balmar setupI have which works fine but still...

If I were keeping the boat - I am selling next Spring - I would likely change to the Leece-Neville and get rid of all the extensive wiring I now have. Selling off my Balmar equipment would likely pay for the change-over. I even have a never-used Leece-Neville 8MR dumb alternator in my spares inventory. Hey, maybe I should do it over the winter. Do you know if it would be difficult to fit your Leece-Neville to a Lehman 120?
 
For specific info on my boat:


I have 3 AGM house batteries, total 360ah at the 50% level.
House charger is 160a.


With 2 80a alternators, they won't have to work hard to charge up the batteries. The temp monitor on the regulators will keep them from overheating. The least of my worries.


My main choice is the wisdom of rebuilding mine or buying new. Right now, I'm undecided.
 
Jleonard, no doubt your Albin setup was more than adequate for your boat. It wouldn't be anywhere close to adequate for my use case. Every boat is different. For example, I mentioned earlier that my two 100-amp Balmars put out 70 amps each. My Magnum 2812 inverter/charger charges to a max of 125 amps so, when cruising, my batteries can potentially be charged more quickly than when plugged into shore power. My house bank (no seprate starting batteries) is flooded 932 ah (nominal) and we generally deplete to 50%. It takes about 5.5 to 6 hours for a full recharge.

I had an "inverter bank" of 4 6V golf carts for 450 AH.
Plus a house bank of 3 group 31 12v starting batteries. I don't remember what that totaled for AH.
And I was running a residential fridge via a 3000W inverter.
 
If I were keeping the boat - I am selling next Spring - I would likely change to the Leece-Neville and get rid of all the extensive wiring I now have. Selling off my Balmar equipment would likely pay for the change-over. I even have a never-used Leece-Neville 8MR dumb alternator in my spares inventory. Hey, maybe I should do it over the winter. Do you know if it would be difficult to fit your Leece-Neville to a Lehman 120?

If you're paying someone to fabricate the second alternator bracket, tensioner, and adding another pulley to the crankshaft, I just don't see you being financially ahead. I would guess adding a second pulley to the crankshaft wouldn't be too difficult, but fabricating an alternator bracket to attach to front motor hanger bracket could get involved depending on what's in the way. For me, the hanger brackets didn't exist (this project was part of the engine swap) designing and building to accommodate the alternator bracket, didn't add that much more in time and materials.

Ted
 
I'll also chime in with my positive experience with Leese Neville. About 10 years ago I had an underperforming alternator on a sailboat auxilliary engine. It was working too hard to replenish a large (840 a/h) house bank whenever batteries had discharged less than half and was running hot most of the time. I read alot written by owners about the Balmar alternators, many of whom complained about less than rated output and premature failures, despite the high cost.

My solution was to purchase a 12v 160 amp Leese Neville refurbished alternator from an alternator/starter rebuilding shop in Baltimore, Maryland. I believe it cost around $250 IIRC, including the core charge. Sorry, but I cannot recall the shop name and I'm not near my boat files to look it up. However, the alternator output was as promised and it gave flawless service until I sold the boat 7 years later. I used the Balmar external programmable regulator to manage the charging parameters.

There are many large trucks that use Leese Neville alternators so it is not difficult to locate either a new or rebuilt/refurbished unit if you choose to go this route.
 
Not what the OP is looking for but an industrial alternator is usually a lot more bang for the buck. I put on a small frame 200 amp brushless alternator from All-Tek Industrial in Alberta.
It happily puts out 185 amps for as long as my 4 Firefly 31's will accept it. $320 CAD.
I added a WA100 regulator and a local small machine shop made 6G belt adapters for a fraction of what the available kits cost.

I'm a blow boater so only about 30 hours per year. :)
 
The 80A Hitachi alternators are relatively low amperage units. Replacement 100A alternators from Balmar are lots more expensive, but include better fan cooling, heavier windings and stronger diodes.

Modifying a Hitachi alternator to work with an external regulator just ups the charging current with no way to remove the additional heat. They may not last long.

I would go with the Balmar alternators. Expensive, yes but they work.

Oh yes, others will say go with a Leece Neville alternator that will be much cheaper. Yes it will but it won't match the Hitachi engine mounts.

David

I've got a Balmar 120 Series 6 on my stbd engine derated to 100 for my 1/2" belt. My port side is a standard 60A alt.

I fried the Balmar one summer of extended bridge photography with extended hours at idle speeds. On my boat, I get just about full output at 11-1200 engine RPM so I'd run it there to recharge after a night's anchorage. A faulty alt temp sensor installation and a lack of adequate cooling caused a catastrophic failure that resulted in a smoke-filled ER underway. I had the alt rebuilt with Balmar parts locally, corrected the temp sense location and added a 12V blower with a 3 inch duct to ensure adequate cooling in the future. Rod Collins/CMS helped be diagnose and solve all the issues.

By the way, Balmar's 70-amp and 100-amp Series 6 alternators reach their peak output at about 3,000 RPM. Remember, most pulleys on alternators are two-to-one so the Balmar on that Albin was putting out at max level at 1,700 RPM engine speed. The Balmar 70-amp version puts out 77 amps when cold and 65 amps when hot. The 100-amp version puts out 106 and 93. Cold is 78F and hot is 194F. I could not find an 80-amp Balmar currently on their website.

My experience is that my Balmar derated to 100A will put out 80-85A net amps at peak operation with a hungry battery bank. When I flip on the combiner to add the port side's output, I now commonly see 95-110A for the initial charging into my new 660AH LA house bank. I noticed a big difference when I recently replaced my depleted 5 yr old bank.


If you're paying someone to fabricate the second alternator bracket, tensioner, and adding another pulley to the crankshaft, I just don't see you being financially ahead. I would guess adding a second pulley to the crankshaft wouldn't be too difficult, but fabricating an alternator bracket to attach to front motor hanger bracket could get involved depending on what's in the way. For me, the hanger brackets didn't exist (this project was part of the engine swap) designing and building to accommodate the alternator bracket, didn't add that much more in time and materials.

Ted

Ted, you should post a few shots of your alts on your engine. Members who have not seen what a 'proper' DIY alternator installation looks like will be impressed!! I sure was!!
 
Rebuilder in Tampa

Hutcherson Starters and Alternators.
 
Always thunk that the batteries did the work (so size them appropriately), and the alternator's job was to simply to bring them back up to charge. So, all this talk of alternators doing all the work is all news to me. Good reading though.

Trainable
Shellerina.com
 
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