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    • #68610
      madsailor
      Moderator

      Hi All,

      I have a Westerbeke 58 and I’m having a devil of a time keeping in belts
      for the alternator (65 amp). I think I need either two belts (and a bigger
      alternator) or a wide serpentine belt – has anyone done that? How do you
      lot put 100 amp alternators on without belt slippage? I have the extension
      pulley on the crankshaft, but it’s so far away from the engine I’d have to
      build a new bracket to use it for anything.

      All suggestions helpful and desirable!

      Thanks,

      Bob

      —
      Bob Fine
      s/v Pelican
      Pearson 424 Hull #8
      http://thesailinglife.blogspot.com
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    • #78733
      RichCarter
      Participant

      Bob,
      I assume that you have the proper belt size for your pulley arrangement. A single belt should be able to handle a 60A alternator. You might check to see that you are using a heavy-duty truck belt. These stretch less than normal belts. Any good automotive parts store can special order these.
      http://www.daycoproducts.com/daycoweb.nsf/8264754109ad09a3862571b000513980/76f8220aaa855780862571b00066aed1!OpenDocument

      You can expect any belt to stretch when first installed. You should retention after 30 minutes of initial use.

      Once a belt has burnished, it should be replaced. Avoid running the engine when the belts are slipping if possible. Reducing engine RPM until you can fix the problem usually saves the belt.

      Here’s a link to a belt tensioning tool. I find this to be the best way to tension my belts.
      http://www.fastenal.com/web/products/detail.ex?sku=0454182

      I have dual-belts on my installation but a much larger alternator. I still must retention my belts every now and then. The tool above makes it easy.

      Rich


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    • #78734
      madsailor
      Moderator

      Thanks, Rich, for all the info – the tensioning tool will be a big help.
      I’d like to know how you mounted a bigger alternator so you could use the
      two belts and still have that ridiculously expensive water pump on its own
      belt.

      I’ll look into the truck belts – the regular and ‘gold’ gateway belts don’t
      last that long as you’ve found out.

      Once again, thanks!

      Bob

      On Wed, Sep 5, 2012 at 8:47 AM, wrote:

      Quote:
      Bob,
      I assume that you have the proper belt size for your pulley arrangement.
      A single belt should be able to handle a 60A alternator. You might check
      to see that you are using a heavy-duty truck belt. These stretch less than
      normal belts. Any good automotive parts store can special order these.

      http://www.daycoproducts.com/daycoweb.nsf/8264754109ad09a3862571b000513980/76f8220aaa855780862571b00066aed1!OpenDocument

      You can expect any belt to stretch when first installed. You should
      retention after 30 minutes of initial use.

      Once a belt has burnished, it should be replaced. Avoid running the
      engine when the belts are slipping if possible. Reducing engine RPM until
      you can fix the problem usually saves the belt.

      Here’s a link to a belt tensioning tool. I find this to be the best way
      to tension my belts.
      http://www.fastenal.com/web/products/detail.ex?sku=0454182

      I have dual-belts on my installation but a much larger alternator. I
      still must retention my belts every now and then. The tool above makes it
      easy.

      Rich


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    • #78735
      quent
      Participant

      Hi Bob-
      Rich makes good points. Perhaps there are a couple other considerations.
      We have two 100 amp alternators on a W-58. One is in place of the original with two 1/2″ belts, the other on a bracket on starboard side originally intended for the refrigeration compressor, also two belts.
      My experience is that the capacity of the alternator is less important than the load. Your 60 amp alternator if maxed out is a pretty big load for one belt. The max we see is about 150 amps split between two alternators. This only happens for a short time, but we still have to adjust the belts infrequently.
      There is a tradeoff between belt contact area and belt tension so for the same load, a single belt will have to be tighter than two belts. The problem is that the belt also drives the water pump and if you make it too tight, the excessive side loading might damage the pump.
      For dual belts, you will need a double sheave water pump pulley. You can either buy one from Westerbeke ($$$!) or have a sheave added from another pulley by a machine shop.
      Quent
      Clairebuoyant, #132

    • #78736
      Anonymous

      Rich,

      Forgive the mechanically challenged among us. How does that Fastenal
      belt tensioning tool work? What do you do with it? To tighten an
      alternator belt, I’ve always losened the appropriate nuts and jacked the
      alternator tighter with a tire iron. Would love to know a better way.

      Tor


      Silverheels, P-424 #17
      http://www.silverheels.us


      Quote:

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    • #78737
      madsailor
      Moderator

      Hi Quent,

      I have a double pulley on the engine – one for raw water pump, one for
      alternator and water pump – I make sure I don’t over-tighten the belts. I
      do have a spare water pump from Rich, I think, but don’t want to replace
      it, that’s for sure. I also have a 4 belt extension on the crankshaft.
      The boat originally had two alternators that were hooked up in parallel
      which you can’t do – at least not if you want your batteries to fully
      charge. So I went to one and everything’s been fine except until the belt
      warms up, the tach doesn’t work so I have to tighten it. Then all is fine
      for a few hours. But the point is, a 65 amp alternator will try to dump as
      much power into the batteries as possible after a couple of days at
      anchor. That’s when the belt is marginal. Two belts would do a better job.

      The problem I have is how to use the other accessory pulleys on the shaft –
      they stick too far out for normal alternators. That’s why I want to see
      pictures of how others have done it.

      Bob

      On Wed, Sep 5, 2012 at 9:46 AM, quent wrote:

      Hi Bob-
      Rich makes good points. Perhaps there are a couple other considerations.
      We have two 100 amp alternators on a W-58. One is in place of the
      original with two 1/2″ belts, the other on a bracket on starboard side
      originally intended for the refrigeration compressor, also two belts.
      My experience is that the capacity of the alternator is less important
      than the load. Your 60 amp alternator if maxed out is a pretty big load
      for one belt. The max we see is about 150 amps split between two
      alternators. This only happens for a short time, but we still have to
      adjust the belts infrequently.
      There is a tradeoff between belt contact area and belt tension so for the
      same load, a single belt will have to be tighter than two belts. The
      problem is that the belt also drives the water pump and if you make it too
      tight, the excessive side loading might damage the pump.
      For dual belts, you will need a double sheave water pump pulley. You can
      either buy one from Westerbeke ($$$!) or have a sheave added from another
      pulley by a machine shop.
      Quent
      Clairebuoyant, #132

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      —
      Bob Fine
      s/v Pelican
      Pearson 424 Hull #8
      http://thesailinglife.blogspot.com
      _______________________________________________
      maillist mailing list

      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

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    • #78738
      madsailor
      Moderator

      Well, Tor, I use a mahogany stick so I don’t damage the alternator or thing
      I pry on. The belt tensioner screws together like a turnbuckle and the two
      saddles rest on the opposite pulleys of the belt. By extending the tool
      against the pulleys, you push on the right place on the shafts (effort in
      line with load) to tension belt. It’s a lot like those shoe or pants
      stretchers except stronger.

      Bob

      On Wed, Sep 5, 2012 at 9:50 AM, Silverheels wrote:

      Quote:
      Rich,

      Forgive the mechanically challenged among us. How does that Fastenal
      belt tensioning tool work? What do you do with it? To tighten an
      alternator belt, I’ve always losened the appropriate nuts and jacked the
      alternator tighter with a tire iron. Would love to know a better way.

      Tor


      Silverheels, P-424 #17
      http://www.silverheels.us


      Quote:

      Original Message


      Post generated from Pearson424 Forum using Mail2Forum

    • #78739
      petedd
      Participant

      When I had a W58, I ran a 140 amp alternator on double A belts. No
      problems at all.

      When you say you are have trouble keeping in belts, what is the pattern
      of the failures? Are they edge worn? Double check that the pulleys are
      co-planar and that the belts are not bottoming out in the pulleys (wrong
      width of belt).

      Good luck,

      Pete

      On 9/5/2012 6:04 AM, Robert Fine wrote:

      Hi All,

      I have a Westerbeke 58 and I’m having a devil of a time keeping in belts
      for the alternator (65 amp). I think I need either two belts (and a bigger
      alternator) or a wide serpentine belt – has anyone done that? How do you
      lot put 100 amp alternators on without belt slippage? I have the extension
      pulley on the crankshaft, but it’s so far away from the engine I’d have to
      build a new bracket to use it for anything.

      All suggestions helpful and desirable!

      Thanks,

      Bob

      _______________________________________________
      maillist mailing list

      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

      Post generated from Pearson424 Forum using Mail2Forum

    • #78740
      RichCarter
      Participant

      Bob
      My original W-60 came with an optional high-capacity alternator. The engine was fitted with four extra pulleys. One belt ran the water pump only. Two ran the refrigeration compressor and two ran the alternator. All brackets were fabricated by Pearson or Westerbeke when the boat was built. I had to replace the original high-capacity alternator at one point in time. I found a local supplier who matched the mounting dimensions. The replacement however was a much bigger unit. I had trouble getting the belts tight enough until I found the tool I mentioned.

      When I repowered, I had two extra pulleys added to my new Yanmar. The engine comes with just a single 3/8″ belt to drive the stock alternator and water pump. There’s no way that a single belt can drive a 160A alternator. I have a refrigeration compressor too which can at times present as big a load as the alternator. I had to get creative. I fabricated a custom mount for the compressor and alternator. It was a bit of work. Both accessories run using the same pair of belts. The original belt still drives the original alternator and water pump but nothing else.
      http://www.richardcarter.net/repower/AccessoryMount.html

      You must be careful to avoid excessive side-loads on a crankshaft. The more pulleys you add, the farther off the end of the shaft you’re center of effort will be. A pulley 12″ from the engine face will load the shaft twice as much as one 6″ out. Excessive side-loads can break your crank-shaft. How much side-load is acceptable is hard to determine. Yanmar publishes a complicated formula in their PTO specs. I checked with Yanmar before designing my brackets to make sure that I wouldn’t void my warranty. When tightening belts, its best to remember to get them tight enough but don’t go nuts with a pry-bar.

      If all you have is a 60A alternator and water pump, I think you’ll be OK if you get a good belt and properly tension it. Let us know how this works out please.

      Regards
      Rich


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    • #78741
      Anonymous

      Hi Bob,

      I upgraded from a 55 amp to a 104, then a 134 the largest
      rating I could get in the same form factor. Both the 104 and 134 chewed
      up single belts. When I upgraded to a double belts on the alternator,
      that problem went away.

      Steve

      On 05.09.2012 05:04, Robert Fine
      wrote:

      Hi All,

      I have a Westerbeke 58 and I’m having a devil of

      a time keeping in belts

      for the alternator (65 amp). I think I need

      either two belts (and a bigger

      alternator) or a wide serpentine belt –

      has anyone done that? How do you

      lot put 100 amp alternators on

      without belt slippage? I have the extension

      pulley on the crankshaft,

      but it’s so far away from the engine I’d have to

      build a new bracket

      to use it for anything.

      All suggestions helpful and desirable!

      Thanks,

      Bob

      _______________________________________________
      maillist mailing list

      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

      Post generated from Pearson424 Forum using Mail2Forum

    • #78742
      quent
      Participant

      I think Rich is correct regarding the problem with side loading. If you can configure the second alternator as close as possible to 180 degrees from the original, much of the side load will cancel out.
      We drive both alternators from one Balmar 612 regulator. The regulator sees it as one 200 amp alternator, with four belt drive, minimal side loading as they are about 150 degrees apart, and considerably less cost than a 200 amp unit.
      One downside for us, the second alternator, mounted outboard to starboard on the old refrigeration compressor bracket, was not quite rigid enough. On the long motor trip up and back to Florida, the boltholes in the alternator wore considerably, as did the bolt. Now looking for a replacement front case for a Balmar 100 amp alternator.
      Quent

    • #78746
      Anonymous

      Ah,so. Thanks.

      Tor


      Silverheels, P-424 #17
      http://www.silverheels.us



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