Belt question~

Discussion in '1947-1954' started by Zig, Jul 22, 2015.

  1. Zig

    Zig Member

    Joined:
    Oct 14, 2006
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    4,860
    Location:
    Pittsburg KS
    So my 228 has the wide 5/8" belt.
    The alternator I will be getting someday soon has a pulley for the narrow 1/2" belt.
    Any problem with just switching to a 1/2 belt instead of swapping out pulleys?
    Thanks!
     
  2. Bill Hanlon

    Bill Hanlon Member

    Joined:
    Jun 4, 2002
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    Location:
    Klein TX
    If only it were that easy Zig.

    Your 1/2" belt is probably 3/8" or 10 mm. Your crankshaft and water pump pulleys are likely 5/8". The 3/8" and/or 10 mm belts will ride on the bottom of your crank and water pump pulley which can cause slippage and early wear of the belt.

    That said, I'm running a Gates 13A1155 belt on my 5/8" pulleys. The 13 in the Gates number supposedly is the measurement in millimeters across the top of the V of the belt. If it were 13 mm, the belt should measure 0.512" and would probably ride OK in the 5/8" pulleys. My 13 mm belt measures 0.490" (12.44 mm). I checked another 13xxxx Gates belt at FLAPS and it was the same. I put some marking paint in the bottom of the crank and pulley and turned the engine over. The bottom of the V of the belt wiped the paint, so it is definitely touching the bottom.

    My belt squeals for just a second when I turn on the A/C compressor with the engine revved up some. So it slips a bit under heavy load.

    Below in a drawing of my belt situation. The blue belt is the 13A1155. The crank and water pump pulleys are 5/8". The front pulley sheave on the A/C compressor has the 13A1155 belt which rides about 1/8" high in the 3/8" sheave. The red belt is a 3/8" belt that takes power from the rear pulley sheave on the A/C compressor to the alternator.

    I'd advise to either find a 5/8" alternator pulley (I may have one, I'll look in the next couple of days, or check with these guys who have alternator pulleys from 3/8" through 3/4") or get a 13 mm belt, which isn't perfect, but would be better than the 3/8".
     

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  3. Zig

    Zig Member

    Joined:
    Oct 14, 2006
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    4,860
    Location:
    Pittsburg KS
    Thanks, Bill!

    I have my original (generator) pulley that I installed on the old alternator.
    I'll go ahead and pull the new pulley and install my old pulley.

    Mine is painted gold to go with the paint scheme of the engine compartment. The new pulley is shiny gold one...
    If anyone would like the new pulley, give me your address.
     

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