eusa1 Posted February 23, 2011 Share #126 Posted February 23, 2011 i'm still sticking to my original thoughts about the failure and the cause. i wish you the best for coverage dave!! Link to comment Share on other sites More sharing options...
SC89Venture Posted February 23, 2011 Share #127 Posted February 23, 2011 Just my 2 cents worth, but it looks to me we have a problem with squareness / perpendicularity problem between the rod / crank / piston bore. This would indicate an out of position problem while parts are being machined / loaded on the fixtures / machine out of square problem. Link to comment Share on other sites More sharing options...
bigmo54 Posted February 23, 2011 Share #128 Posted February 23, 2011 Yamaha will have there own story but the piston looks to have had water in it for some time looking at the pits,hard to say with pics but this will be covered.The inside looks clean and over speed would streach rod bolts.The wrist pin is ok,they will or should replace or short block,if not lawyer up. Link to comment Share on other sites More sharing options...
Guest PlaneCrazy Posted February 23, 2011 Share #129 Posted February 23, 2011 Man... this thread is tense for all of us! Especially people who still are under warranty, like me (4.2 years left). Without the parts in hand, I can only speculate, but to me, it looks like what a hydro lock would look like. I've never seen it personally, but since the head of the piston doesn't show any impact damage and there's no signs of a seizure on the sides of the piston, I'm leaning towards theory that the piston hit a cylinder full of fuel/anti-freeze/whatever and then Pascal's law took over and BOOM! I have to say you are taking this remarkably well Dave77459. Where I work, I have seen some pretty catastrophic engine failures on large jet engines worth close to a million bucks each. We always get them into the shop and start digging into them to find out what went wrong and we all have the same thing on our minds ..."Please God, don't let them find a wrench with my initials on it sitting in the compressor section!" But this is your bike and may end up costing you a lot of money. I know that what I paid for my venture is probably the most money I have ever paid for any "toy" I ever owned. I'd be almost ill if I had to make payments for the next few years on a bike that was destroyed. I just hope that you have a favorable outcome with all the parties involved and you are back riding again soon. Link to comment Share on other sites More sharing options...
dingy Posted February 24, 2011 Share #130 Posted February 24, 2011 Just a random thought on the Hydro lock theory. How would a motor that is cruising along at maybe 3500 RPM, just all of a sudden, ingest enough water to cause the hydro lock to happen in the first place? It would not take a lot of water, granted. A blown head gasket could be an explanation. Blown head gaskets are not a rare occurrence, and they are not often attributed to this type of failure. If the piston did hydro lock, what would be the cause relationship factor that then cause the rod to snap. The rod snapping is likely due to what is referred to in engineering as an object in tension, meaning the part was being stretched. The hydro lock would have the opposite force applied, which is a compressive force. If this were to occur, I would expect that one of two things to occur. First the wrist pin junction point would fracture on the piston and it be driven up towards the top of the piston, or second the crankshaft would be torqued very badly. I do agree with the assessment that the piston does not appear to have contacted the valves though. There is apparent damage in one picture that appears the rod broke the skirt of the piston out. This possibly could be an indicator of why there is no valve contact evident. If the failure occurred at the point when the piston was being pulled down by the rod, thus the rod was in tension, the piston would continue downward until struck by the end of the broken rod as it started it upward movement. This impact broke out the side of the piston and caused enough deflection of the rod to cause it to go through the cylinder liner sleeve, then the block. Any bending that the rod now displays would very possibly be caused by it being driven through the cylinder sleeve at high velocity. If this happened around 3500 rpm, which by unchecked quick calculation equals 17.7 MPH of rod speed at mid stroke. Think of the damage that a car gets if it were to hit something at this speed. Now, how many times did the rod bang on the sidewall before breaking through. To me the slight twisting could be expected. This all is just speculation though. Gary Link to comment Share on other sites More sharing options...
ragtop69gs Posted February 24, 2011 Share #131 Posted February 24, 2011 Dave, If I may ask, how many miles were on your motor when it let go ? Link to comment Share on other sites More sharing options...
Dave77459 Posted February 24, 2011 Author Share #132 Posted February 24, 2011 Dave, If I may ask, how many miles were on your motor when it let go ? I may not know much, but I know this: the odometer read 55,802. Dave Link to comment Share on other sites More sharing options...
Yammer Dan Posted February 24, 2011 Share #133 Posted February 24, 2011 Water, yes. Antifreeze will form a black crust, and it takes Seafoam to remove it. Let's hope it was a bad casting on the rod, or a head/head gasket failure. I really believe in it but in this case I really don't think the Sea-Foam will help....:rotfl: I don't see why it is taking Yamaha so long to do what they should. REPLACE IT!! Link to comment Share on other sites More sharing options...
royalstar09 Posted February 24, 2011 Share #134 Posted February 24, 2011 (edited) 20 yrs of looking at engines, inside and out, broke and just wore out........I can tell you that one is broke..... I really hope that Yamaha steps up for your sake. Keep us informed on the progress please. I did reword this after realising with the help of another member it sort of sounded as though I may have pointed fingers. Never was my intentions for those who seen this before editing. Edited February 24, 2011 by royalstar09 Link to comment Share on other sites More sharing options...
ragtop69gs Posted February 24, 2011 Share #135 Posted February 24, 2011 I may not know much, but I know this: the odometer read 55,802. Dave That engine's internals look way to clean for this to be an issue of lack of proper maintainance. Hydro lock... no way and I see no evidence of detonation. It looks to me to be a materials failure. I have to wonder if maybe the piston skirt broke and wedged between the the piston and crank counterweight, causing the rod to fail. If you look at the last 2 pics posted, at the 7 O-clock position you'll see a small break where contact was made, that is what makes me have this suspicion. I think, Mama Yama will step up to the plate on this one. Link to comment Share on other sites More sharing options...
Redneck Posted February 24, 2011 Share #136 Posted February 24, 2011 I read the post before looking at the pics. It is hard to tell with the photos but it looks like the upper half of the rod is bent and it doesn't appear to have been hit after it broke. That leads me to believe the rod was probably bent before it broke. You said it would not start before the ride did it crank and not start or would it not crank? Link to comment Share on other sites More sharing options...
autopilot Posted February 25, 2011 Share #137 Posted February 25, 2011 My instinct is that they come back saying that you over-rev'd it repeatedly over time and fatigued the rod to failure. A. your statement that both yamaha & dealer theory would potentially cost you. B. The apparent lack of lubing issues with the piston sides (no seizure) and lower end bearing OK per dealer mechanic. Further, there are no impact indicators on the deck of the piston or any mention of bent/stuck valves due to improper oiling. C. The broken rod ends "look" like failure of a progressive old fracture...IE repetitive stress over time. hairline crack...to failure. D. the only hydraulic sort of failure at this point that I can see (since there was no mention of failed headgasket, etc.) or obvious presence of anti-freeze on the piston, would be from being flooded with fuel. I recall someone said something about bike not wanting to start earlier...pre-ride. If there is a carb leak over to that cylinder when it was stopped. that could easily do it...proving it would be a bear, however. Along this same line; they may say that carb sync. was off and cause a backfire which would potentially overstress the rod. then subsequent to that event it failed. AND, as additional fodder, they would likely throw in the old aftermarket oil & filter as a contributing factor........ Normally I wouldn't be so negative, but I had my upper teeth pulled and the plate is rubbing a little bit and the pain meds aren't helping so I'm a little out of sorts. It's a small wonder I'm making any sense at all! That's my 2 cents. FWIW. Link to comment Share on other sites More sharing options...
exrsa1 Posted March 4, 2011 Share #138 Posted March 4, 2011 Hello, any updates since the last post? Thanks Ex Link to comment Share on other sites More sharing options...
Kregerdoodle Posted March 4, 2011 Share #139 Posted March 4, 2011 Dave will probably post an up date, but yamamama is fixin it on their dime. Hello, any updates since the last post? Thanks Ex Link to comment Share on other sites More sharing options...
flb_78 Posted March 4, 2011 Share #140 Posted March 4, 2011 Dave will probably post an up date, but yamamama is fixin it on their dime. NICE!! Link to comment Share on other sites More sharing options...
Monty Posted March 4, 2011 Share #141 Posted March 4, 2011 I told ya it was Hydro-lock! Link to comment Share on other sites More sharing options...
Dave77459 Posted March 4, 2011 Author Share #142 Posted March 4, 2011 Dave will probably post an up date, but yamamama is fixin it on their dime. I've been conflicted on posting, because "it's complicated." When all the dust has settled and Yamaha has, in fact, paid the dealer, then I'll say why it is complicated. For now, the dealer has authorization for warranty repair. That is true. I was told it would take 3-4 weeks to marshal the parts and get it back in one piece. "The crankcases, crankshaft, rods, pistons, etc on the bottom end will be new. The cylinder heads will be reused as will a few other parts." Dave Link to comment Share on other sites More sharing options...
Kirby Posted March 4, 2011 Share #143 Posted March 4, 2011 Glad to hear the good news. Can't wait to hear the details. Keep us posted. Link to comment Share on other sites More sharing options...
Yammer Dan Posted March 4, 2011 Share #144 Posted March 4, 2011 I would tell them I don't trust rings that have been pulled. They will break. Link to comment Share on other sites More sharing options...
flb_78 Posted March 4, 2011 Share #145 Posted March 4, 2011 I would tell them I don't trust rings that have been pulled. They will break. I would assume that since they're putting new pistons and cases on it, they would probably replace the rings as well. Link to comment Share on other sites More sharing options...
Pam Posted March 4, 2011 Share #146 Posted March 4, 2011 I would try for new ring as well. The engine will be new with old rings,(55000 miles) and we all know what happens next. Oil burn Keep us up to speed Dave fsc Link to comment Share on other sites More sharing options...
Snaggletooth Posted March 4, 2011 Share #147 Posted March 4, 2011 Good news to hear. Glad they are rolling in the right direction for you. Mike Link to comment Share on other sites More sharing options...
cecdoo Posted March 4, 2011 Share #148 Posted March 4, 2011 Great news! Hope it all works out in the end:080402gudl_prv: Craig Link to comment Share on other sites More sharing options...
MiCarl Posted March 4, 2011 Share #149 Posted March 4, 2011 I would assume that since they're putting new pistons and cases on it, they would probably replace the rings as well. Link to comment Share on other sites More sharing options...
eusa1 Posted March 4, 2011 Share #150 Posted March 4, 2011 dave, you may consider having them to inspect the clutch friction plates that will be affected from this failure, or at least request them to put comments about them in your copy of the completed repair. mike Link to comment Share on other sites More sharing options...
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