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  1. #1
    raiderteen's Avatar
    Join Date
    Nov 2007
    Marion, Illinois

    Old School Gurus - Pump Conversion Question

    Hey guys,

    Been a long time member due to ownership of a raider 1100 since 2005. Well I recently picked up a LS2000 jetboat equipped with twin 1200 Non-PV motors. I am in early planning stages of a 4 stroke conversion and have a pump question...

    The 1100/1200 pumps used the completely removable pump including the duct as opposed to the newer 1200PV and 4 strokes having the pump duct space glassed in and the rest of the pump bolting up. Also, the newer 4 strokes use a larger diameter driveshaft and larger couplers as well.

    I think I have four options listed in order of best to worst.

    1st: Modifying a newer 155mm stator to work with my existing pump setup. Which if I am correct would allow me to use the larger driveshafts seen on the 4 strokes due to the bearings being of the larger center diameter. The only issue here is if the larger driveshaft would fit through the driveshaft tube? I would obviously have to upgrade to the newer midshaft/intermediate bearing carrier as well.

    2nd: A custom or modified midshaft coupler allowing me to use my complete existing pump setup. My only worry here is strength of the smaller diameter driveshaft. But maybe it wont be a issue. This is a boat so I have to remember its not going to get thrashed on as much as jetskis do.

    3rd: A custom driveshaft or modified 4 stroke drive shaft that would allow me to thread the larger 4 stroke coupler in place while using my existing pump setup. This would be expensive potentially. And might not even work due to the bigger end for the coupler not fitting through the driveshaft tube.

    EDIT 4th: Retap the original motor couplers to fit the larger threads of the 4 stroke crankshafts. Allowing me to use all of the existing pump setup. I consider this the best option at this point. Thanks TimeBandit for the suggestion (from another thread)...sometimes the easiest options get ignored when overthinking things.

    Which option is most feasible? I know the stator can be converted to 2005 style. In theory I would use the stock 05 bearings for use with the larger driveshaft...if it would fit through the tube. Addicted has done this here but swapped the bearings to the 1100/1200 size bearings.

    I wish I had a larger driveshaft laying around for mock up as I have one of the pumps removed from the boat currently for a impeller housing replacement...
    Last edited by raiderteen; 03-21-2019 at 10:06 AM.

  2. #2
    raiderteen's Avatar
    Join Date
    Nov 2007
    Marion, Illinois
    Edited first post to add 4th option...

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