3,2,1...meltdown!

bluelightning

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Nov 15, 2005
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bristol CT
hey all, posted a topic a few weeks ago on my perilous journey up to pittsburg NH, followed by my sled dying within 20 minutes of arrival. finally got inside the old girl, and here are some pics of my misfortune for your amusement



these are pics of the mag side cylinder, which i was suprised to see was NOT stock, but the other 2 are. what you dont see is all the nickle built up in the exhaust port. cylinder is fried. found a replated for 225 plus shipping and all that nonsense, so i just went with a new one for 315. i was pleasantly surprised to find out that the parts weren't as costly as i was expecting...only about 850 all together. Gonna do it right, which apparently the first owner did not do. all oem, doing all 3 pistons. not just throwning some junk piston in without even honing the cylinder.

now any ideas of what i should be looking for that caused the meltdown? PS bottom end looks fine

PPS at least this lack-of-snow has given me time to fix the old girl....if there was snow i'd be kicking myself in the morning when i woke up
 

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i would check your jetting. clean the carbs. especially that carb for that cylinder. not sure if you can hone nicasil though. yep, OEM is the best way to go
 
Woah, I also had a burndown down on the mag side at the snodeo last year, my piston looked almost exactly like yours. The top ring was broken just like yours, and had a hole in the same place too, looked like someone shot it with a .22.
;):D I also had a bunch of pieces of the rings and piston in my muffler. :Moon:
 
too lean for one reason or another. Make sure jets are rich enough, not that they are a few sizes leaner than stock. Make sure the jets are all CLEAN! And as waterfoul said make sure the crank seals aren't leaking.
 
What year is the motor? I believe (correct me if I'm wrong) that in '98 and '99 the big jet is on the mag side and on '00 and up it's on the PTO side. Even if the sled is an '00/'02 I'd still check the year of the motor. If that's an older motor then you'll jet it wrong every time, and you already know the end result.



:die:
 
Also, take a look at the jets, as it is easy for someone to have put a Keihn jet in place of a Mikuni.
 
got all the parts from a local dealer, did some pricing out online and it ended up being about the same with shipping. and plus this place has been good to me, they took great care of me with all my gear so i didnt mind giving them the business. thats my next step, pulling the jets and posting what i turn up with.

still scratching my head over why that piston was already replaced though.....


and another thing, am i doing the right thing by replacing all 3 pistons? i mean, i'm already in there, i figured why not if i have the $ right? but is it overkill?
 
bluelightning said:
and another thing, am i doing the right thing by replacing all 3 pistons? i mean, i'm already in there, i figured why not if i have the $ right? but is it overkill?

Depends on how many miles are on it, but if it has over 3 or 4,000 miles i would replace the pistons while you are in there.
 
If your other 2 pistons are stock and are ok i see no real reason to change them if anything i'd just put new rings on them while you're in there might as well that way all three cylinders would have stock pistons with brand new rings can't go wrong there. Good luck to you those motors are pretty simple to rebuild done a few of them and can be done in a night pretty easily. Hope everything works out and she runs like a champ.
 
who was the dealer, if you dont mind me asking. I am the same way, my dealer has helped me out a lot, so I ended up paying a little more to get my simmons from him. and here comes the shamless plug.........Pittsburg Motorsports. Pittsburg NH, Vince and his brother Kevin Judd. great place to do business :)
 
bluelightning said:
hey all, posted a topic a few weeks ago on my perilous journey up to pittsburg NH, followed by my sled dying within 20 minutes of arrival. finally got inside the old girl, and here are some pics of my misfortune for your amusement

Nice intro!
 
yamaholic, odometer says 2700 but speedo was broken when i bought it, so could very well be much more. figured might as well just spend the extra 150 and have the piece of mind knowing that the top end is pretty much brand new.

viperguy, dealer is land 'n sea down here in waterbury. been a 'doo and cat dealer for some time, but just started up with yamaha's. i had some experience with pittsburg motorsports on my trip when this happened....and i have to say my experience wasn't as pleasant as yours was. but then again, i was pretty bitter about my sled at the time

and bischof, it seems as if i suceeded lol
 
really? suprised you had a bad experience, and sorry about it :( first interaction was when my grip pulled off my old 97 600sx. went there to ask them if they had glue and what to use. they sold me some nice stuff made for th ejob and asked if I had a warm place to put it on. I was renting a cabin up there so the answer was no :( they said, tell ya what. drop it off here at closing time. we will put it in over night and in the morning first thing, with the sled warm, we can put it on for you. did it free of charge. been great ever since. got me out of a LOT of jambs over the years, and always right away. couldnt be happier :) always nice to have a dealer that treats you right, no matter the brand!
 
i was staying up at robin's cabins, right off of back lake (where i began having problems). my group decided on my behalf that it was a good idea to limp it to pittsburg motorsports to see if there was perhaps something simple i was overlooking? got there, no one wanted to help me out. had to practically beg to get a tech to come outside and just glance at it for me. he just listened to it run and said i was f*cked, and then waited around with his hand out!!! like i said, maybe it was because i was bitter about the confirmation of what i tought the problem was, but on the same hand it was very unprofesional and i would have loved to have them service it if the tech wasn't such a deuche
 
lol! never had ANY problems like that, but I know they have been getting jerked around by people this year, so might have just caught them on a bad day :(
 
just an update everyone......crank seal bad on mag side.....guessing this caused the meltdown and the lean idle i had before anything else happened?
 
bluelightning said:
just an update everyone......crank seal bad on mag side.....guessing this caused the meltdown and the lean idle i had before anything else happened?

At least you found the problem. Sucks to get a used sled and then have problems like this. Hope it hasn't put you off the sled too much.
:die: bad mag seal!
 


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