trannmission?
- Thread starter 2006 blaster
- Start date
ahh that sucks. so u need a new piston and to get it bored. the shop to bore it will tell you the size. btw i think the reason why it overheated is because the oil injection failed. i would take that POS out of there, plug up the nipple on the carb so its air tight, and Premix that Motha!!!! haha
no..it over heated i think..it was pumping oil..i had just filled he tank and there was the right amount gone after i got it home...and i was in sand and it was hot out..
Yeah, sand puts a huge load on things, especially at low speeds with no airflow.
We load test our bikes in a big sandpit to check if everything is working.
If everything is right, jetting, air leaks, oil etc, it should be able to play all day in a hot sand bowl. Something is wrong.
Listen to Blaaster. Good advice.
We load test our bikes in a big sandpit to check if everything is working.
If everything is right, jetting, air leaks, oil etc, it should be able to play all day in a hot sand bowl. Something is wrong.
Listen to Blaaster. Good advice.
ok so i called the dealer and they said they only service junky polaris wheelers..so i took off the top end and my bore looks good...my pistion has half of the skirt broken off and all of that is in the bottom end..sooo i got a small hose into the bottom end and vacuumed all the shavings out and a couple big chuncks off the pistion..what caused the pistion to break??..was there to much it pistion slap?
more than likely a combonation of high heat and piston to cylinder clearence beyond the spec limit
(piston slap) you didn't hear it ???
you'll need a new piston and bore, plus split those cases to "try" and flush all the shrapnel from the bottom end.
your vaccuum method did not even get close to removing all the shrapnel
my experience has been...if that piston shattered into a million tiny pieces, chances are very good that you "will not" be able to get them all out, no matter how much you flush those bearings
and reassembling the bottom end without getting the bottom end rod bearing (crank rebuild) and main bearings replaced, it will eventually go bad from the very tiny missed pieces of piston you did not get out of all the bearings, which will take out the new top end when it goes, costing you more money in the end
ask me how i know this ?
if it were me, i'd do a full rebuild
if you cannot find a local shop to do this,
you know my suggestion....KOR I:I
the phone number is in my sig below
Man if that piston has dropped its guts into the crankcase it is going to need more than a good suck from a vacuum cleaner.
No amount of flushing will remove all the debris that the piston shed.
The cases need to be split and either new bearings fitted, or a really good clean of the old ones. I prefer to use new bearings and seals.
You will need to inspect the cases thoroughly as it has been known that a chunk of piston may have forced itself between the crank and the case, doing damage to it.
Broken piston skirts are usually caused by the piston being worn and/or by a sloppy bore.
Overheating can also cause piston skirt failure
You need to get the bore measured to make sure it is servicable.
No amount of flushing will remove all the debris that the piston shed.
The cases need to be split and either new bearings fitted, or a really good clean of the old ones. I prefer to use new bearings and seals.
You will need to inspect the cases thoroughly as it has been known that a chunk of piston may have forced itself between the crank and the case, doing damage to it.
Broken piston skirts are usually caused by the piston being worn and/or by a sloppy bore.
Overheating can also cause piston skirt failure
You need to get the bore measured to make sure it is servicable.
Yes and no, too much piston slap and too much rpm and too many hours on the piston are the usual causes of breaking a skirt. Broken skirts are the Blaster's only real weakness. The proper fix is to split the cases, but I have gotten away with a topend only many times. Besides cleaning out the bottom end, you have to check for cracks. The crank will jam the skirt against the case and crack or break the case at the bottom or into the gearbox side. Using Varsol or kerosene will to clean out the bits and check for leaks. Leak testing before you took it apart would have been a good idea, to know if you have a crack into the gearbox or if you need new seals.
Check for cracks, flush bottom end, measure bore, new piston to fit, you're good.
Edit; These other 2 replies came in while I was typing, and I totally agree with them.
I do my own work and know the work and risk involved. I can get in there, flip the case over and clean with a vigour knowing the consequences of any bits left in there. I can take the risk, but can you? After the cost of a new piston, fitting it, the gaskets, and the time involved, can you afford to have the piston scuffed up or the crank going bad from bits left in the bottom end?
There is never enough time or money to do the job right the first time,
but there is always time and money to do it over.
Check for cracks, flush bottom end, measure bore, new piston to fit, you're good.
Edit; These other 2 replies came in while I was typing, and I totally agree with them.
I do my own work and know the work and risk involved. I can get in there, flip the case over and clean with a vigour knowing the consequences of any bits left in there. I can take the risk, but can you? After the cost of a new piston, fitting it, the gaskets, and the time involved, can you afford to have the piston scuffed up or the crank going bad from bits left in the bottom end?
There is never enough time or money to do the job right the first time,
but there is always time and money to do it over.
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I am really not in favour of just flushing the bottom end, in my opinion the cases must be split and everything fully cleaned, preferably replaced.
I have seen way too many "flush fixes" come back to bite the person who did them.
It only takes a small grain of unflushed piston, to wreck a motor.
Flush and refit a top end if you choose to, but really, consider it carefully, is it worth the chance.
I have seen way too many "flush fixes" come back to bite the person who did them.
It only takes a small grain of unflushed piston, to wreck a motor.
Flush and refit a top end if you choose to, but really, consider it carefully, is it worth the chance.
thanks for the help..the jug really does look good soo i dont really think it need to be bored over.. but idk what to do on the bottom end..ive ordered new gaskets and a pistion and rings..126 dollars..i really dont want to put soo much money into it..how much are new bottom end bearings and seals?
you really needed to measure that bore before ordering a piston.
be sure to check the new piston to the bore size and be absolute certain it is within specs, or you'll be headed down the same road again real soon
usually when it is out of spec and causes a skirt breakage, the bore is worn beyond the service limit and should be bored to the next available size
main bearings aren't expensive, $50 or so, but can you do a bottom end yourself ???
the bottom end rod bearing(crank rebuild) will need done by a professional
i don't believe there is anyone on here doing DIY crank rebuilds
In one of the sections there's a thread stickied on " cheap crank rebuilds " if I remember correctly they claim it costs $100 shipped for blasterforum members.
i measured my bore and it was 66mm exactly..and the pistion should be here any time..we flushed it out and dosent get hung up at all any more and i turned it over forever..thanks for the help
Hey, I have been there.
Little money and not wanting this thing to get complicated and take more time or money.
I have pulled the motor out of the frame or even flipped the frame over, sloshed it out with some sort of solvent, heck, even soapy water and the pressure washer followed by kerosene or varsol or what have you, and got by. It has bit me on occasion, had a crank go soon after or scored a piston with a little chunk I didn't get.
Hillbilly mechanics at its best. Not the right way to do things, but sometimes we do.
I've looked at a $400 machine and said "I'll toss in another $100 and some effort,
if it goes, it goes, if it blows, it blows". Sometimes you win, sometimes you lose.
Maybe I shouldn't talk about it because it may encourage others to think it is an easier way?
About the bore.
Why did the skirt break off in the first place?
One likely cause is too much bore clearance.
You say "measured my bore and it was 66mm exactly".
The problem is, there is no such thing as "66mm exactly".
Was it 66.00mm or 66.09mm or 66.15mm because all of these measurements will cause more problems.
I sense your rush. I have been there before too.
Better would have been to get the piston fitted properly to the bore, even if it was to the next oversize.
Yeah i see where you are coming from. But couldnt over heating of caused the skirt to break? idk..I just think that since this wheeeler had like no miles on when i bought it i was thinking this had to be self inflicted since these engines go a long time if rode right???
Dunno about anyone else I love to win.
There is no way that I would fit a new top end to a motor that could have only one grain of piston lurking in a bearing.
The risk is far too great.
Lt me correct this statement.
These engines go a long time if JETTED right!
Change the breathing, the elevation, the temperature, the conditions and some other variables and you must change the jetting to suit.
yeah..im not wooried about jetting at all..i dont have any preformance parts exept boyesen super stock reeds..and they are like the stock ones ..just cheaper and last longer..my blaster came from a dealer from around here..so elavation should be good..
I remember thinking like this when I was younger.
Logically deducing things instead of physically checking them with my own eyes.
Please do not take this as a personal criticize.
We all seem to do it until we find that all the logic and figuring in the world does not make up for what is solid and real.
Example in point: why did the skirt break? "couldnt over heating of caused the skirt to break?"
Yes, but did it? And if it did, why did it over heat? Jetting?
You can argue "im not wooried about jetting - stock - came from a dealer- -should be good"
but that won't cut it when it blows up again.
You put it back together the exact same but expect different results.
You could take a guess and just go buy a richer than stock main jet. Would that solve it?
Who knows for sure? Not you or I or anyone, it was a guess, not based on evidence.
Not likely to fix it, the problem could have been a dozen other possibilities.
You have to check.
What is your bore size, exactly?
Does the original piston show signs of overheating?
What is your main jet size? Your needle and where?
Did you check for air leaks before or after?
Any signs of detonation? Timing OK? What do the piston and head look like.
(the piston will show signs of proper jetting in the black on the top.)
The step from logically thinking something out to rationalizing doing less work can be a small one, but often leads to bad falls.
You can argue and debate like a lawyer, but it doesn't make it real.
