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  • #16
    Re: Break-in oil

    The table spoon of oil down the carb throat is mainly for the crank bearings. When I build a motor I use my finger to coat the cylinder walls with the 2 stroke oil if you didn't apply any oil to cylinder walls that might be what caused it to lock up.

    I would use the starter with no plugs and crank the motor like 10 seconds then wait 60 then crank again 10 seconds maybee 8 times and put 2 tablespoons of oil down carb throat to make darn sure the crank is lubricated. Starting it would be your call I certainly wouldn't rev it just idle it for about 15 seconds and listen for noise. Also the pre-mix is 40:1 for break in I went back and fixed my post.

    Also I see where you are from VA I use to live in VA Beach and did a lot of jet sking there.


    Good luck,

    Joe
    Last edited by Joe Snuffy; 05-09-2005, 10:52 PM.

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    • #17
      Re: Break-in oil

      Im with Joe take it down rather than risk more if any damage. Also yes you need to run 40:1 on top of injection.

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      • #18
        Re: Break-in oil

        I am running 40:1 premix on top of the oil pump. Since there is no signs of top end damage, do you really think i need to tear it down again? It turns by hand, and i took the plugs out and cranked it over, evrything sounds fine. I don't mind tearing it down again, i just don't want to tear it down for nothing.

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        • #19
          Re: Break-in oil

          I would first remove the pump and see if that makes a difference in the way it cranks over, thus eliminating it as a problem. If it then cranks over better, I'd be looking at the pump as the culprit. If not, remove the intake rotary valve cover and crank it over. If it makes a difference, figure out what was wrong with that.
          If it still cranks over too hard to crank with the sparkplugs in the head, I'd be eliminating the starter motor and cables and battery as the possible culprits.
          If all else fails, return the motor to SBT and use your warranty.
          Bill O'Neal <br>
          WCM
          <a href="http://www.watercraftmagic.com"

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          • #20
            Re: Break-in oil

            Bill,


            I already eliminated the pump, it has a new starter and battery. Could i have just overheated it causing the pistons to expand and seize temporarily? And this is not an SBT top end.

            Thanks

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            • #21
              Re: Break-in oil

              It is not an SBT motor, sorry, I thought it was.

              Maybe you did not bore it out far enough for the pistons you installed? What is your clyinder wall to piston clearances ?

              Still could be the RV cover if you had removed it and re-installed it? Pinched oring maybe? Too much sealant?
              Bill O'Neal <br>
              WCM
              <a href="http://www.watercraftmagic.com"

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              • #22
                Re: Break-in oil

                No need to apologize.

                Anyways, i never removed the RV cover to do the top end, the lower half is also new, but i blew the top end last year. I never had a problem with the RV cover or valve(valve is new), and i didn't use sealant.....i was told the oring was good enough, was i steered wrong? I'm just looking for answers before i start tearing this thing apart again. The piston to cylinder clearance i am not sure of, i had a local shop do it, they said they would match the piston and rings to the bore.

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                • #23
                  Re: Break-in oil

                  In that case I would go with the tight piston theory....... Try holding the rods in your hands and cranking the motor over with the starter to see if you even need to tear the crankcase apart.

                  Other possible causes I can think of would be a rusty magneto flywheel causing the magnets to expand towards the stator and dragging on the stator, or the ring gear on the flywheel is coming loose and moving back towards the engine cases and dragging on the cases. You can check all of that by removing the magneto flywheel.
                  Bill O'Neal <br>
                  WCM
                  <a href="http://www.watercraftmagic.com"

                  Comment


                  • #24
                    Re: Break-in oil

                    Thanks Bill,

                    I will check the magneto flywheel first, i would much rather tear the front cover off than tear the cylinders back off. If that's not the problem i guess the cylinders come off again.

                    Thanks for the help, keep ya posted.

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                    • #25
                      Re: Break-in oil

                      alright,

                      Here's the thing now. I charged the battery back up and it spun good and acted like it wanted to fire, but would not. I checked the magneto, all looks good. Plugs were oil soaked.
                      Should i yank the starter and see if i have a crap one(again)? It never locked up again, but when i spun it by hand via the driveshaft, it made a weird noise, like maybe the bendix was hanging up in the flywheel. What do you guys think? It just will not turn over unless i play with it on a fully charged battery, then even whe it will spin for a few, it hesitates and don't want to fire up. I have good spark, bad starter?

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                      • #26
                        Re: Break-in oil

                        crap, i think i founf the problem.....ideas please.


                        My manual says the limit is 82.50 mm, my pistons are 84.00 mm ( my clearance is .0050 in.(.127mm). My piston box says it replaces a 661P8(that's wiseco). Says it's for a seadoo xpx 785 rave. I have a 787

                        Wisco part# iss 779MO8400

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                        • #27
                          Re: Break-in oil

                          BTW, i poured oil on top of the cylinders when i had the head off, from what i could see, not much passed by.

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                          • #28
                            Re: Break-in oil

                            the engine part is right but if you are that far out and it is tight you may have to reduce your pistons or have them bored more.

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                            • #29
                              Re: Break-in oil

                              I would inspect the starter. It might need lubricating/cleaning where the bendix engages the flywheel. You should try turning the bendix with your hand and simulate its going toward the flywheel and see if it is in a bind before cleaning and lubricating to see if that might be your problem. I have seen them become corroded and not engage properly which on my own ski made the engine seem locked up but it was actually the starter bendix hung up against the flywheel. I turned the pto back and forth a couple of times and it freed up the bendix which might get you out of trouble on the water but then I still cleaned and lubricated it. I would also clean and inspect all the battery cables on both ends. I use a sand paper to clean the cables making the copper shinny/new again. I would also clean where it grounds to the motor with sandpaper. Normally with those clean and a fresh charged battery the starter should work if it doesn't it might need a new starter but I think your on to something.

                              Joe

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                              • #30
                                Re: Break-in oil

                                well, i did have a crap starter, thank god it was warrantied.....it starts now, but still have the mystery of the engine locking up. Should i just take the few weekends and couple hundred for a gasket kit and tear the whole engine apart(everything sounds fine though)? I ran it at idle for 10 miniutes on the hose, then backed it in the lake and let it run for 15. Don't be shy, if you pros think i should tear it down i will.

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