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Discussion Starter · #1 ·
I have a 94 vmax that has always bogged midrange loading you would say it is piped so I made surethe jetting is correct the belt is new with the right amount of freeplay. now the midrange bog disappeared but the thing was only pulling 7000 rpm I thought was running rich cause it was so warm out. I ran out of gas, whn I restarted the snowmobile it was running on one cylinder. I limped it home, pulled the spark plugs. One spark plug had no gap in it due to impact. Piston is okay, found a tiny metal, looks like a ball bearing, stuck in the spark plug. I assume it's the reason for spark plug damage. i regapped the spark plug, the engine runs on two cylinders, but the cylinder with the plug damage appears to be pushing oil out the exhaust right at the manifold. Is this ball bearing looking part out of the oil injection? I'm guessing the overoiling of this cylinder is the high end bog issue. Am I on the right track? The other cylinder spark plug is nice chocolate brown like it should be. Any ideas?
 

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not to spoil your day but i would suggest pulling that side apart. your ball bearing looking thing is more likely something more significant like part of a ring or part of a needle bearing, or worse yet, a crank bearing.

the oil is injected into the fuel pump on that sled, i believe, so the chance of any part of the oil pump coming through would be quite slim.

worn rings or stuck rings would cause excess oil out the exhaust. i would be right on figuring out what pinched the plug before causing more catastrophic damage.
 

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Discussion Starter · #3 ·
argh

not to spoil your day but i would suggest pulling that side apart. your ball bearing looking thing is more likely something more significant like part of a ring or part of a needle bearing, or worse yet, a crank bearing.

the oil is injected into the fuel pump on that sled, i believe, so the chance of any part of the oil pump coming through would be quite slim.

worn rings or stuck rings would cause excess oil out the exhaust. i would be right on figuring out what pinched the plug before causing more catastrophic damage.
mission accomplished you wrecked my day i'll tear it down and look thanks
 

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Discussion Starter · #4 ·
rings maybe?

thought for the fun of it should do a compression check running 100 psi both sides is that to low for this machine has to be getting pretty bad right? thinking rings and check for cylinder wear? any thoughts
 

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your numbers would depend on how you did the comp test and the quality of the compression tester. i would say it to be a bit low.

for a quick partial view of the pistons, pull the pipe and the exhaust manifold off. rotate the crank slowly and you will be able to see the lower portion of the pistons.

you can also shine a penlight into the sparkplug hole and look at the top of the piston. i would bet the one with the closed sparkplug has some serious hammer marks on top.
 

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Discussion Starter · #6 ·
i shone a light down the spark plug hole already and I can't see any marks at all if fact it looks just like the other side i'll pull the pipe off and look into it a little more closely one other thing could that piece have come through the transfer port and possibly be out of the bottom end? just a thought....
 

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Discussion Starter · #8 ·
before I tore anything apart i looked at everything as best I could and all appears to be normal so I put fresh plugs in it and fired her up seems to be running smoothly i used my mechanics stethescope to listen to the enigne and I can't hear anything that would make me think bearing the side that pinched the plug sounds no different than the other side now I'm wondering if it just ingested something through the airbox we were riding pretty hard and I had tipped it over pretty good a few times that night I really don't want to tear it apart just to find out i'm paranoid seeing as my son's bravo is already down for repairs (it needs crank bearings) how's that old saying go "the lord hates a coward and the partsman love the brave" or something like that:)
 
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