Balmar High Capacity alternators

Cspirit

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Does anyone have any experience of fitting one of these to a Volvo 2003 engine? I have spoken to the very helpful chap at Merlin in Poole - they supplied all the kit for a complete rewire of our boat's electrical system a few years ago. He advises that given we have a house battery bank of 300amp and that we now rarely get shore power charging, we should replace our puny standard alternator with a Balmar with a capacity of around 100amp.Until recently we were in marinas every few days so we could charge up the batteries fully but we are now in Greece where shorepower is limited and we find that we cannot achieve the fully charged 13.5/14 volts that we had from shorepower when we just charge with the engine.

Any advice much appreciated and in particular, any experience of fitting one to the Volvo - Balmar claim that it should be a direct swap.
 
I had 70 A one fitted to my Volvo MD7A, when I increased the battery bank to cope with extra electrical loads. It was quite straightforward, Balmar make various types to fit different engine mounts, and one of these is specifically for Volvos.

Unfortunately when I replaced the MD7 with a Beta there was not physically room in the engine bay for the Balmar, so I now have a 70A Beta alternator.

I have been intending to sell the Balmar, but have just not got around to doing so.
 
Balmar alternators are offered as "premium" products, but there's nothing magic about them. To increase your charging efficiency, you may need a higher-output alternator, but you definitely need a "smart" regulator (Adverc, Sterling, Balmar, etc).

A Balmar 100A alternator and Balmar smart regulator will cost you well over £1000. I'd suggest you look at a Prestolite 90A alternator instead - you can get one complete with an Adverc regulator for around £400 from Adverc. This will transform your charging efficiency. Around 90-100A is the most you can sensibly drive on a single V-belt.

But with only a 300Ah house bank, you'll rarely see a high charge for very long. So a good way forward would be to get the Prestolite kit and spend some of the saving on increasing the battery bank capacity.

I have a 90A Prestolite alternator installed as a second alternator on my 2003T, with an Adverc regulator, and this keeps my 630Ah house bank nicely topped up.

Incidentally, Balmar alternators are made by Prestolite.
 
Have just been discussing this very issue as my Volvo (2030) alternator packed up last week. The advice from the electrician sorting out the charging was that with my bank (270 amps) the 60 amp standard alternator was enough. The batteries would not be able to absorb the extra from the 100 amp Balmar, and he suggested double belts would be required to drive it reliably.

Probably better to consider one of the charge boosting systems which are claimed to charge quicker with a standard alternator.
 
A Balmar alternator and Balmar Max Charge regulator from memory will cost about £950 God I didn't think I paid that much. They are effectively plug and play but to get my rev counter working on a Yanmar I had to make an additional connection not provided for on the Balmar harness it was very simple on the 6 series that I purchased. I don't know about the Volvo but it will not be any worse. The output is very good and will certainly give you good charging with the Max charge regulator.

I use a single belt (segmented) which will be different to the standard one used with the old alternator as the pulley centres will be different, there is no dust and whilst carrying two spares I have not had to change the belt since installation three years ago. Much of that is down to the ramped charge availlable from the Balmar regulator and getting the right belt in the first place NOT from a chandler!

Reccomended
 
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A Balmar alternator and Balmar Max Charge regulator from memory will cost about £950 God I didn't think I paid that much. They are effectively plug and play but to get my rev counter working on a Yanmar I had to make an additional connection not provided for on the Balmar harness it was very simple on the 6 series that I purchased. I don't know about the Volvo but it will not be any worse. The output is very good and will certainly give you good charging with the Max charge regulator.

I use a single belt (segmented) which will be different to the standard one used with the old alternator as the pulley centres will be different, there is no dust and whilst carrying two spares I have not had to change the belt since installation three years ago. Much of that is down to the ramped charge availlable from the Balmar regulator and getting the right belt in the first place NOT from a chandler!

Reccomended

PeteHB can you give the make and part number of the belt you use. I will see if I can find one of that type for my installation. I have a Balmar 100 amd with a smart regulator. I struggle to avoid belt slippage.
 
The belt I use is a Contitech FO-ZXPA 1060 but it is notched / segmented but not a toothed belt which is a different type of drive belt I am not sure that there is a designation for the notched belt other than the description but what they are designed for is going around small pulleys like those on an alternator.

I got mine from a bearing / belt supplier WYCO used to be Fenners but there are lots most towns will have one, if you describe what you want and even take in a belt they will be able to supply, what is really imprtant is to get the section right so that the belt does not bottom out in the pulleys.
 
Cspirit,

You don't mention the ampage of your original alternator, but probably 70, or even 90 amps.

Your batteries will absorb such a high amperage for only a few minutes, and only if they are well down.

A more powrefull alternator is not really usefull, but a smart regulator (Adverc is my favorit)shall help your alternator feed your batteries more efficiently.

I would suggest install an Adverc (or any other brand) and use the spared money to add one battery to your "domestic" bank. Then try this configuration for at least one year.

That's what I did long ago, and thats what I still have.

Good luck
 
The house bank of 300 ah will accept 75 amps max if they are flooded batteries up to about 80% state of charge. Gels and AGM batteries will accept more current up to 80%. The last 20% will taper off rapidly and take many hours if only using the engine for charging.
You state that you cannot achieve the 13.5/14 volts that your shorepower charger provides. The regulator, either internal or external, should be set at 14.4 volts for flooded batteries. If it is set at 13.8 you will never get a full charge regardless of how large the alternator is.
I would suggest a separate 3 stage regulator for your existing alternator as a first step. If you do decide to get a new alternator the regulator will work with it as well. The best choice would be a 75 to 90 amp Prestolite, which is really not much different from a Balmar except for the powdercoating and price. By staying under 100 amps there will not be any belt problems. A Prestolite 90 amp alternator with a good reg like the Balmar MC-612 dialed back to about 80% output for longer life and the optional temperature sensors - both battery and alternator ideally - will give you a durable charging system and a fast charge.
 
overheating

Remember that installing a smart regulator also puts extra strain on your alternator. It will develop more heat because of this. So make sure the thing doesn't cook itself to death.

on back of my alternator is a regulator close to the brushes with the electronics "potted" with a type of epoxy .to keep them dry etc . This melted( temp over 40 degrees in turkey ) and the sticky melt ran into the brushes and prevented them contacting the commutator when cold this leaving the charge light on for about 2 minutes before heat allowed the carbon brush to move forward and make contact . had to remove alternator clean out and repot with a higher melting point epoxy .

Oh for an external regulator easily accesible to save a dirty back straining job of removing an extra alternator . . I have to one 30 amp accessible and one 70 amp at the back of beyond
 
Remember that installing a smart regulator also puts extra strain on your alternator. It will develop more heat because of this. So make sure the thing doesn't cook itself to death.

The really smart ones have altenator temp sensors and battery temp sensors and do a cool down cycle if an overtemp situation develops. I have the alt temp sensor but not the bat temp sensor.
 
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