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  1. #1

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120

    1050 build question

    I am building my 1050 AGAIN, seems my front crank seal leaned out the mag cylinder, got the new piston, my question is...... Why does this piston have a hole machined in it just under the ring grooves???

    Also, when i go back with the new crank, do i loctite the bearings, or will the cases hold them sufficiantly? It looks like the old crank bearings may have spun a little??
    none of the bearings are seized up, but they sure make noise when spun (surface rust)!


  2. #2

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120
    Also, is there only the one seal beind the stator?? if so, it sure seems cheesy!!

  3. #3

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120
    anyone?

  4. #4
    Banned User
    Join Date
    Jun 2010
    Location
    Milwaukee WI
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    16,708
    +1
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    Cases should hold the bearings. Yes there is only one seal on the mag end.

  5. #5

    Seals

    I will be the first to tell you that if you ride in salt water.....the real seal will hold up for a little but then it will swell and want to push out on its on with the compression.

    Get 2 genuine polaris seals and convert it to the 1200 engine configuration. It seals up great and you have double protection.

    Invest in this upgrade!!!!! $30.00 for both.

    The front seal shouldnt push out as it is pressed in from the back side of the stator cover..unless you hammered it in crooked, it should hold up very well. i have only seen and read of these seals being damaged by heat (removal of flywheel with torch) and improper install. The rubber lips on them do wear and when they go, you will not know unless you find oil in your stator cover. If the stator cover isnt sealed well, prepare for water leaks, and a wicked air leak that will lean that mofo out.

    also if the crank bearings spun, you might have caused damage to the cases. There is a small margin for error when it comes to the bearing and case clearance. If the line bore on the cases are damaged, the bearings will not be retained by the cases. There are pins in the case as well as a snap ring that will hold the crank in place but the line bore is the key.

    just my two cents...

  6. #6

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120
    how is the 1200 set up?

  7. #7
    Tony's Avatar
    Join Date
    May 2007
    Location
    North Carolina
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    1,760
    +1
    38
    Use alot of sealant between the cases and stator housing.

  8. #8

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120
    i destroyed 2 mag pistons in an hours ride time. Pulled the motor, tore it compleley down, did not see any oil in the stator cover at all, nice and dry.
    carbs are 100% clean, and built with kiehn parts, 138 mains, all i could figure was the mag crank seal was leaking, but i did not see any sign of leaking?
    i did notice i had nice brown gritty bearings, so i bought a crank from a board member.

  9. #9

    Join Date
    Dec 2009
    Location
    Alvin,TX.
    Posts
    120
    i also need ANOTHER dome for this motor!

  10. #10
    Quote Originally Posted by gregr1971 View Post
    how is the 1200 set up?
    in the 1050, you have 2 snaps rings. in the 1200 you only have one. You will install the snap ring on the Mag side of the engine in the groove. On the PTO side, you will take the 1200 style oem seals and install them. If i recall, there was a snap ring in the pto end that must be removed so you can use the ring groove as the seat for the first 1200 seal. Then you will place the second one in the outer groove.

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