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O.S. 120 FS Surpass (1) ?, Pump....... converting from pump to non pump....

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O.S. 120 FS Surpass (1) ?, Pump....... converting from pump to non pump....

Old 09-06-2016, 07:29 AM
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Richard39
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Default O.S. 120 FS Surpass (1) ?, Pump....... converting from pump to non pump....

Is this difficult and what parts do I need....? I have a parts engine, Magnum 120 FS, can I use some of the parts from that engine.... I understand that parts are not available for the early O.S. FS Surpass (a model 1, I believe...)
Old 09-06-2016, 10:19 AM
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Bax
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To convert from a pumped version to a non-pumped version, you'll need a new crankshaft, new rear cover, new intake pipe, and a new carburetor. If you can carefully grind off the drive pin from the end of the crank, then you won't have to get one of those. Almost all of the parts for the non-pumped engine are still available, or on backorder. Just look for the parts for the FS-120 Surpass-E.
Old 09-06-2016, 03:21 PM
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Richard39
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Thanks... Is that the drive pin on the crankshaft that turns the pump....? Appreciate your help.... Richard
Old 09-07-2016, 10:50 AM
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Bax
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Yes, the drive pin on the crankshaft drives the pump. If it's left on, the non-pump rear cover won't fit, and you need the non-pump rear cover because it has the proper mounting for the non-pump carburetor.
Old 09-07-2016, 01:36 PM
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Richard39
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OK, I understand.... Thanks... Richard
Old 05-13-2017, 08:11 PM
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Bax,
I just converted an FS-120 to non-pumped operation and would like confirm the cam breather tube needs to be connected to the intake pipe.

thanks
george
Old 05-15-2017, 07:23 AM
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It's not necessary. Just plug the nipples.

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