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  1. #171
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    1. You were trying different things with the AAT. Depending on how much load you placed on your engine, you may have altered the fuel requirements.

    2. I don't think a slight indent of the piston is going to drop you 30 PSI. But all that carbon below your bottom piston ring might. How much time is on your pistons?

  2. #172
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    1. You may be right but my thought on that: I'm already running a slightly lighter pitch prop with a 3mm larger exit nozzle. Theoretically that should put a lighter load on the motor. Plus the rpm was still well over 7900. Maybe I'm missing something?

    If I was having fuel demand issues, I would think my rpm would be low and would be dropping when holding wot but that wasn't the case.

    Literally I came around a buoy, let off for a couple of seconds and then tried to get back on the throttle. That's when the bogging started...it was sudden and wasn't doing it all day.

    2. The pistons aren't that old, maybe two seasons..rings are brand new, replaced when I did the rebuild. The blow-by seems normal...? Or does it really look that excessive?

  3. #173
    rpa101's Avatar
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    It's the mag that's low? And it's the mag that looks washed in the pic of the head ? Is it possible the crank is out ? From water ingest?

  4. #174
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    Quote Originally Posted by rpa101 View Post
    It's the mag that's low? And it's the mag that looks washed in the pic of the head ? Is it possible the crank is out ? From water ingest?
    I suppose anything is possible at this point until it is ruled out. I do believe the MAG can't be knocked out of phase due to the way the crankshaft is constructed. The only way it could be is if the flywheel sheared the key or the stator got turned. I've checked the phase of the crank and it is still dead on so no spun crank.

  5. #175
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Quote Originally Posted by hyoctane23 View Post
    1. You may be right but my thought on that: I'm already running a slightly lighter pitch prop with a 3mm larger exit nozzle. Theoretically that should put a lighter load on the motor. Plus the rpm was still well over 7900. Maybe I'm missing something?

    If I was having fuel demand issues, I would think my rpm would be low and would be dropping when holding wot but that wasn't the case.

    Literally I came around a buoy, let off for a couple of seconds and then tried to get back on the throttle. That's when the bogging started...it was sudden and wasn't doing it all day.

    2. The pistons aren't that old, maybe two seasons..rings are brand new, replaced when I did the rebuild. The blow-by seems normal...? Or does it really look that excessive?
    1. Were you running a shuttle in the AAT? That adds load.

    2. It's possible to burn down a piston during part throttle. Actually more likely. You're not getting as much fuel as WOT, and the ignition timing is more advanced.

    3. Tough to say if they are 2 seasons old. If they were new and i saw that much blow bye, I'd look into that for sure.

    Try pouring a little oil around the piston and try doing another compression reading. If your reading comes up to normal, that's prob your low compression.

  6. #176
    Rasta Mon Condoms We Be Jammin!!!!! TxVirageTx's Avatar
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    maybe another water leak?at the head gasket?explains the lower compression and the clean dome

  7. #177
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    The thing is that the clean dome is actually normal and the other two that are black are the odd balls! So far I have not found the "smoking gun" with this issue:

    -I have torn two of the three carbs down and they all didn't have anything wrong with them...still have to do one more.
    -The stator ohmed out within spec.
    -The stator didn't rotate out of alignment with the crank case split.
    -The flywheel didn't shear the woodruff key.
    -The crankshaft didn't twist and is still in phase.

    So far the only thing I can think of is maybe the CDI took a crap? I have another one from my other ski that I will try if I get the same issue.

    Maybe I got some bad fuel? I won't be using the fuel that was left in the tank nor any that I bought from that station.

    The inline fuel filter seemed to have a bit of resistance to it. I'll change that out too...

    Since I have the pipes out, I'll also be doing a leakdown test to be sure I didn't get an air leak somewhere.

  8. #178
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Someone suggested to me about your low compression. Did you ever heat up the engine when you were having the triple pipe overheat issue? It was suggested that Nikasil will glaze from the heat. If that happens, you're not going to get good ring seal.

    If you're saying the oily mess is not normal, that looks like excess fuel/oil that mixes with water to me. Looks like the gunk inside the waterbox if you're running too rich.

    1. What oil are you running?

    2. Do you torque your head bolts in the proper sequence and in "steps"? (9 lbs, 14 lbs, 18lbs)

    3. Do you ever recheck your bolts?

    You can try a different CDI and see what you get, that's an easy swap.

  9. #179
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    Quote Originally Posted by xlint89 View Post
    Someone suggested to me about your low compression. Did you ever heat up the engine when you were having the triple pipe overheat issue? It was suggested that Nikasil will glaze from the heat. If that happens, you're not going to get good ring seal.

    If you're saying the oily mess is not normal, that looks like excess fuel/oil that mixes with water to me. Looks like the gunk inside the waterbox if you're running too rich.

    1. What oil are you running?

    2. Do you torque your head bolts in the proper sequence and in "steps"? (9 lbs, 14 lbs, 18lbs)

    3. Do you ever recheck your bolts?

    You can try a different CDI and see what you get, that's an easy swap.
    The oil on the domes is straight up oil, doesn't appear to have any water mixed in with it.

    The cylinder that had the pipe heating issue was the PTO, which still had great compression before I pulled the engine apart. Admittedly, I should have poured a bit of oil in the MAG cylinder to check to see if the compression came up indicating a ring issue but I didn't think about that at the time.

    I'm running the stock oil injection system with Amsoil Dominator oil.

    I always torque the head in the sequence as shown in the manual. In fact, I have written the sequence on top of the head in marker to ensure I go in the proper order...and with the 3 steps as indicated in the manual.

    I don't check the bolts once they're torqued. I will remove the bolts in a reverse sequence. I honestly don't remove them in a stepped torque sequence. All bolts were still tight when I removed the head.


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