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Happened again must be deeper issue

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Discussion starter · #21 ·
jcs003 said:
I think its related to frame mounting. something might be tweaked on your frame or how you mounted it. for example; tightened up one of the motor mounts before getting the others snugged. mounting the engine should be done using the same methods for mounting the head or clutch springs. tightening a li, at a time in a criss-cross pattern in my opinion. it probably wont make a difference on a lower powered engine, but on a big bore its magnified.

john
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Not sure it's mounting as I been running big bore in this frame for the past 6 years started with pro-x 310, then 330, then 350. I know this is more powerful than them but can't be much more than my 350 kit and never had a problem. Also been running my oof drag pipe for over a year with out problem have it mount to peg with stock hangers and keep two springs on Manafold no solid mounts. I thought maybe its because I don't run headstay but Carlos said he has a number of these motor running without headstays. So really lost. Just glad BDT and Carlos are so good to work with, never expected so much help. Again thanks to Carlos and BDT.
 
#22 ·
etccb mentioned this first, but look at that pic real close, notice how the under side of the nut left marks imbeded on some of the cylinder casting & then on that front edge, it didnt touch at all.
Now I'm just guessing, that this is an on going thing same as with the Pro-x & ESR cylinders, at least those that my hands have touched over the years. That mountng area of the cylinder casting, needs to be machined square & flat so that the nut will have a straight pull on the stud instead of an angle.
What I'm saying, has no reflection what so ever, on the quality of work being done by BDT/Carlos/Rob & is just one of those thing we all hope that is not the problem.
I've thought for years, when looking at the Pro-x cylinders, the contact marks left on the cylinder casting from the nut. Maybe one out of 100s of casting, the nut might make full contact, but normally most all have only a small % of contact to the mounting area, so one would wonder how the studs have lasted as long as they have.

Next thing in order, would be some sort of machining tool invented to machine those areas of the casting to insure a solid square fit.

Let me ask this, is there a head stay in place ?.
I was told quite a few years ago, take that head stay off, says it will free the top end up & let the engine rev. Oh yes it will do that, but be ready to replace those case studs when you least expect it.
An old dog never gets to old to learn something new & since I been putting the head stay back in place, not broke a case stud since.
Neil
 
#23 ·
Im sure the failer is not from how it was mounted in the frame.not having a headstay only hurts the frame ,not the motor.The motor is used as part of the frame structure and not the other way round.As far as I know the cr 500 uses the same stud (A little longer than oem 250r)and it never has issues breaking from to much horsepower.These studs ,should be plenty strong to handle the load.we all know that there strength is in the pull and are not designed to carry loads in any other direction.the question is ,why is this stud be loaded unevenly
 
#25 ·
Looking at pictures can be misleading, some think the marks left in the cylinder stud/nut pockect earea are the nut not sitting flat, that is not correct. Notice the black out line of the nut base on the cylinder, it has been sitting flat, and the machined notch to clear the nut diameter is what we do to these cylinders prior to assembly; we machine the base flat and clear the nut diameter....that is what you are seeing.

Having dozens of these Sphynx 363Rs in the field, all with UCCR's around 14.5/1, and none have had this issue...this is a very important fact. Now, since we fully inspected Michael's engine the first time the stud broke and found nothing we could see or measure that would indicate a good reason why the stud broke, I am leaning towards a case or cylinder issue that is not visiable or measureable. The immidiate solution for the customer is to replace the engine outright, period.

The longer task for us is to examine, run, test, ect..this particular engine and see why it keeps breaking the same stud...till then; everything is pure speculation.

Carlos
 
#27 ·
wolvman99 said:
Carlos please let me know what you find out . We have a 330 pro x before now with a + 4 mm hot rods crank . It has a history of breaking the same stud periodically . Our cyl has the same marks that the OP has.
Click to expand...
Definitely...this will be a good post & thread to make. I intend on posting what we find, and the solution...might take us a few weeks or month as we are extremly busy & have a lot going on.

Carlos
 
#28 ·
i just replaced all 4 of my studs on a 330cc ProX, the stator side first vibrated the nut off the stud, then i replaced the nut and the stud stress fractured, when removing the jug to replace all 4 studs the right front stud was yielding at the same location. just under the nut. it was not broke yet but it wouldn't of taken long id say ill have to take some photos of it starting to yield.<br><br>ive heard from the previous owner this was not the first time its happened, the first stud fracture on me was about 80hours into the topend life.<br><br><br>
 
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#30 · (Edited)
acecarlos said:
Looking at pictures can be misleading, some think the marks left in the cylinder stud/nut pockect earea are the nut not sitting flat, that is not correct. Notice the black out line of the nut base on the cylinder, it has been sitting flat, and the machined notch to clear the nut diameter is what we do to these cylinders prior to assembly; we machine the base flat and clear the nut diameter....that is what you are seeing.
Carlos
Click to expand...
Could the black really be a sign that it maybe wasn't sitting flat? Maybe the flange was catching the edge of the cyl just a bit on the right in the photo? Just bouncing ideas around for the 250r family to learn and gain knowledge for future troubleshooting.
 
#31 ·
Those old Honda cases are taking a beating with all those bigbores out there
I'm pretty sure those 20 something year old cases weren't made for pumas,sabers or even the bigger proxs...haha
Don't get me wrong I love my 310 and my prox 370 that isn't built yet
 
#32 · (Edited)
I just looked at the photo again and I may be wrong but I feel stronger then ever that the washer or flange is riding on its edge in the left of the photo and wedged on the cyl on the right in the photo. If I am correct it is a simple fix and not really a product problem, just a mistake in assymbly. If I am not correct then I am not correct. The black should not be able to get under the washer or flange if it is seated correctly. Again, this is just what I am seeing from the photo as we all bs and discuss what the problem could be. Whatever the case may be it is being corrected and we will all learn something to watch for going forward.
 

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#33 · (Edited)
etccb said:
I just looked at the photo again and I may be wrong but I feel stronger then ever that the washer or flange is riding on its edge in the left of the photo and wedged on the cyl on the right in the photo. If I am correct it is a simple fix and not really a product problem, just a mistake in assymbly. If I am not correct then I am not correct. The black should not be able to get under the washer or flange was if seated correctly. Again, this is just what I am seeing from the photo as we all bs and discuss the problem. Whatever the case may be it is being corrected and we will all learn something to watch for going forward.
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You know you (we) can beat this horse to death etccb. As I stated earlier; this is all speculation until we receive the engine.

"The black should not be able to get under the washer or flange was if seated correctly"...you don't have a 'clue'to what you are saying etccb...FYI; the nuts are Oxide Black, the cylinder is polished aluminum...you get a Black ring everytime you tighten the nut to the cylinder and it has any amount of riding time, specially when the nut seats properly onto the cylinder, the 'Black Oxide' rubs onto the Polished aluminum cylinder. Plus, as I already stated; the nut pockets are machined flat, and the nut head is recessed to clear the nut shoulder...

The immediate 'fix' is Michael is getting a new engine ASAP, actually this week so he can keep his Memorial Day planned trip. If every other builder or manufacture treated their customers with this type of respect and service instead of passing the blame to the customer, and 'making it right' ASAP even when the cause of the failure has NOT been determined (could be our fault or it could be the customers) we would have much healthier 250R community...

Again; bottom line is once the engine arrives, then we can inspect it, and through testing, measuring, ect...determine why the same stud broke twice.

Carlos
 
#34 · (Edited)
Thats nice carlos. A "CLUE" ? I was not attacking or posting as you would post if this was a product or service that was provided by someone else. Not everyone has dirty little goals to their posts that they make. I find it strange that you would respond like that to me and what I posted but.. We all know that if this was from someone else that you would be pouring nitro on it bashing the product and builder badly and making sure that everyone got to read it 5000 times. I was not doing that or intending that type of thing. I believe that photo tells a lot even knowing that a black flange nut would leave its own black contact proof. I also believe based on looking at the photo that the black may not be residue from a black flange nut or washer at all. I do not "KNOW" that though. In the photo to the left of the stud it looks like a nice clean scratch size mark from the washer or flange riding on its edge and on the right the same type of clean scratch like force connection from the washer or flange against the cyl. This type of force could break a stud. Again, as I posted whatever the problem may be the 250r family will all learn about something to watch out for in the future.

I want whoever reads this to know that this is not what I was trying to do in the previous posts. I posted based on that photo as I would no matter where the item came from. Please look at the photo and read what I posted and every post that I have made in this thread before judging my intentions. I do not want to be percieved any differently.
Good day.
 
#37 ·
etccb said:
I just looked at the photo again and I may be wrong but I feel stronger then ever that the washer or flange is riding on its edge in the left of the photo and wedged on the cyl on the right in the photo. If I am correct it is a simple fix and not really a product problem, just a mistake in assymbly. If I am not correct then I am not correct. The black should not be able to get under the washer or flange if it is seated correctly. Again, this is just what I am seeing from the photo as we all bs and discuss what the problem could be. Whatever the case may be it is being corrected and we will all learn something to watch for going forward.
Click to expand...
etccb ,you are not alone.I see the same thing as you are seeing,but Im not part of the faithfull followers,so what do I know
 
Discussion starter · #38 ·
The reason choose BDT was because of how good the customer service, I always heard how good it was but I got to say it even better than advertised. Never heard of another builder replacing the whole engine so I won't have to deal with trying to trouble shoot the problem and just waste more money down the road. Plus making sure I should get the motor to me in time for my Merorial weekend. Can't ask for more than that. Thanks again to Carlos and the whole BDT team.
 
#40 ·
I work in the oilfields and sometimes we would have to break flanges on steam or oil piping and we would have to replace the bolts and nuts afterwards
The rule was too replace it with a bolt long enough to engage the whole nut thread ,nothing more ,nothing less
The reason I say that is a article came out about saying if there was too much bolt sticking out past the nut ,they would snap or loosen up and even fracture over time
And the pipes and flanges would go between heat and cold ranges all day
 
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acecarlos
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