Maine,
Was wondering if you did the serpentine upgrade yet? No one has come out with a set up for Universals, as far as I know they’re still working on it. There is a lot available for Yanmar, Westerbeke and even Perkins engines. No standardization and every install is slightly different which makes it hard for them to market one. I began machining my own pulleys after an extensive search for prefabricated ones came up empty. I have the alternator (Ø2.25) & water pump (Ø3.00) done. Everything looks good so far. They fit and there isn't any interference. I got all the info needed from Gates Engineering and the Machinist Handbook. I decided to use a 6 groove K belt because the 10 groove J belt is a bit wider and I wasn’t sure either would fit. I now think a 10J would work. I've had a hard time tracking down the water pump max RPM. Torreson Marine told me 3000 rpm which makes no sense seeing the top end of the M25XP is 3300 and the pulley ratio is 5" to 3". Because I can't put a RPM on the pump I've decided to make the pulley diameters the same size as the original ones. I will be removing the crankcase pulley to make one to match. I will machine them from aluminum and have them anodized. I'm not sure if I'll do a type II or Type III (hardcoat). I think the hard coat will wear and stand up to a marine environment much better. I will post sketched drawings when I'm done if anyone is interested. Did/does your upgrade require removing the crankcase pulley or does the new one slip over it? I ask because if it slips over like their Yanmar video then the water pump pulley has to be bigger to maintain the same ratio. That crankcase pulleys look machined verses the Universal's are cast and don't lend themselves to a slip over style. The face doesn’t look too flat. Correct me if I’m wrong but the use of TefGel is for ease of removal later. I’m feeling a little better than when I started that this will work out.
Was wondering if you did the serpentine upgrade yet? No one has come out with a set up for Universals, as far as I know they’re still working on it. There is a lot available for Yanmar, Westerbeke and even Perkins engines. No standardization and every install is slightly different which makes it hard for them to market one. I began machining my own pulleys after an extensive search for prefabricated ones came up empty. I have the alternator (Ø2.25) & water pump (Ø3.00) done. Everything looks good so far. They fit and there isn't any interference. I got all the info needed from Gates Engineering and the Machinist Handbook. I decided to use a 6 groove K belt because the 10 groove J belt is a bit wider and I wasn’t sure either would fit. I now think a 10J would work. I've had a hard time tracking down the water pump max RPM. Torreson Marine told me 3000 rpm which makes no sense seeing the top end of the M25XP is 3300 and the pulley ratio is 5" to 3". Because I can't put a RPM on the pump I've decided to make the pulley diameters the same size as the original ones. I will be removing the crankcase pulley to make one to match. I will machine them from aluminum and have them anodized. I'm not sure if I'll do a type II or Type III (hardcoat). I think the hard coat will wear and stand up to a marine environment much better. I will post sketched drawings when I'm done if anyone is interested. Did/does your upgrade require removing the crankcase pulley or does the new one slip over it? I ask because if it slips over like their Yanmar video then the water pump pulley has to be bigger to maintain the same ratio. That crankcase pulleys look machined verses the Universal's are cast and don't lend themselves to a slip over style. The face doesn’t look too flat. Correct me if I’m wrong but the use of TefGel is for ease of removal later. I’m feeling a little better than when I started that this will work out.
