Horrible ATS experience

This is the factory Cummins bolt. It has the slot on the male end.
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My question still stands.
How long is the shortest period of time for the "fatigue" Beach marks tour develop?
Could all of them have happened in less than 1 second?
I'm asking this for obvious reasons.
And feel the need to add to the metallurgy subject.
 
It's late and your right about unknown bolt quality.
I iirc this was a shouldered bolt with built in washer if you will.
Does anyone know what grade of bolt the factory Cummins tensioner bolt is?
I have a cheap grade 5 bolt in there now but do want to change it Because it's a Panama hardware
store bolt which are usually low quality.
 
The b.s. and "expert opine" is super deep in this thread. Sorry for your luck, kit looks a bit sub-standard eh?
 
kawgomoo said:
The b.s. and "expert opine" is super deep in this thread. Sorry for your luck, kit looks a bit sub-standard eh?
Click to expand...
I'm curious just which parts of this thread you take exception to. I don't recall anyone declaring their expertise in the matter. If anything, the discussion has given the OP the ability accurately portray what has happened, rather than make a nearly baseless allegation like so many (idiots) on here do, and lessened the ability for anyone to refute his claim.

If it were me, and the assembly allowed, I would modify the threaded area to allow the grip of the bolt to sink in, relieving some of the sheer stress from the threads of the bolt.

Ask your metallurgical confidant if the bolt being under torqued could have initiated the failure.
 
waywardtravel said:
It's late and your right about unknown bolt quality.
I iirc this was a shouldered bolt with built in washer if you will.
Does anyone know what grade of bolt the factory Cummins tensioner bolt is?
I have a cheap grade 5 bolt in there now but do want to change it Because it's a Panama hardware
store bolt which are usually low quality.
Click to expand...

I will ask some guys at Caterpillar what they think for a timeline on fatigue fractured bolt, as I don't have an answer.

Send me the bolt if you like, we have a microscope at work that can take a detailed pic of the fracture that I can post up.

X2 on the under torque. If the joint is allowed to move it can flex the bolt at it's weakest point, the threads and initiate a fatigue crack.
 
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To ALL the people who have stated this is a "FATIGUE FRACTURE" and insinuating that this happened over a period of time somehow insinuating that the bolt was the problem or cause of this event.

Could this (EVERYTHING IN YOUR ANLYSIS OF THIS BOLT) have happened AFTER THE BELT JUMPED A PULLEY?
I mean AS A RESULT of tensioner contact, belt jumping pulley, the only final pulley that can't jump is the tensioner pulley which is now under the force of the crank pulley and still wrapped around the fan drive pulley?

This is critical to anyone understanding your definition of fatigue fracture and how to identify it.

Or you could answer this direct question which I have asked many times,
Could everything displayed in the picture have happened in less than 1 second?
 
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My opinion on what you are asking is this: the bolt you have shown us cycled until it failed. This is not consistent with a high speed, singular event. From what I'm gathering, the bolt was not over tightened, and th fracture doesn't display signs of overly long run time with damage. What was previously stated could hold true, after initiation, the void might not have been permitted to close (tension from side loading) so polishing isn't evident.
My feeling is that the bolt already had a stress riser where it failed, reassembling it with higher load finished it. I don't have access to data to dictate how long it took, but it was not a singular explosive event.

I did have a great example of a ductile fracture but I think I turned it in to our training dept.
The head of #2 main bolt popped off, the crankshaft fractured but was still running.
I can post some examples tomorrow if you would like to reference them.
 
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waywardtravel said:
To ALL the people who have stated this is a "FATIGUE FRACTURE" and insinuating that this happened over a period of time somehow insinuating that the bolt was the problem or cause of this event.

Could this (EVERYTHING IN YOUR ANLYSIS OF THIS BOLT) have happened AFTER THE BELT JUMPED A PULLEY?
I mean AS A RESULT of tensioner contact, belt jumping pulley, the only final pulley that can't jump is the tensioner pulley which is now under the force of the crank pulley and still wrapped around the fan drive pulley?

This is critical to anyone understanding your definition of fatigue fracture and how to identify it.

Or you could answer this direct question which I have asked many times,
Could everything displayed in the picture have happened in less than 1 second?
Click to expand...

:Edit: Never mind good luck
 
I see deflection to the direct question which doesn't validate your opinion much.

I'm not debating cycles. I'm specifically asking about TIME FRAME.
There is many different possible scenarios that could cause stress cycles in this failure.

What is "high speed"

Please answer in fraction of seconds, seconds, minutes, hours, days, months, etc.

For me to put any weight at all into your theory or analysis based off the two photo's you have to state you belief clearly.

TIME FRAME hypotheticals. Minimum and maximum if you prefer.

Everyone is using science to say something and exactly nothing at the same time.
 
And thank you for the offer to send the bolt but I'm a bit far for that and have 100% confidence in the buddy connection. They build 100,000hp + engines and he does have access to all tools, machinery, and chemicals necessary to evaluate.

It's how far he can go or wants to go for basically "fun"
 
waywardtravel said:
And thank you for the offer to send the bolt but I'm a bit far for that and have 100% confidence in the buddy connection. They build 100,000hp + engines and he does have access to all tools, machinery, and chemicals necessary to evaluate.

It's how far he can go or wants to go for basically "fun"
Click to expand...

then stfu already .
 
By all means have your buddies at Caterpillar look at the photo if you see relevant.

Bottom line.
I don't suspect the bolt being the root cause but a few of you do.
If you can factually say that the bolt photo'd couldn't have started fracture and finished (parted) within the 1/4 mile run then it's really not relevant information.

If you can say that this (slow) fracture MUST have taken days or months then it applies in my head.
 
I'm done with your challenges. Provide the analysis and root cause from your man in the shadows. The fact that you don't have a distinct time line means your account of events holds no more merit than ours.
 
I agree it's not smart to point at the bolt being the cause unless you know something that's all.
I didn't start any challenges but respect opinion for what they are.
A few people insinuated fatigue fracture which happens over time but haven't ever said a fatigue fracture could happen in seconds or less. That needs to be pointed out to retain creditability.
The same if I'm saying something wrong.
I do know the ATS pump pulley is misaligned.
I do know the tensioner bolt broke between the 1/4 mile point and shutdown 1/8th mile max later.
I do know many people have a very tight belt on this ATS kit,
Mine put's the tensioner pulley and AC pulley very close together running and "probably" makes contact on rapid decel. That part is not proven yet.
 
I want to try and use a new ATS CP3 bracket before modifying.
They told me last Thursday it should ship tonight.
On Friday when I called for tracking they said backordered.
Then it should ship Monday but I haven't heard anything yet.

I have the twin pumps on right now. I'll install the new controller they sent tonight and see if it fixes the cold start issue. then go back to single for weekend races.

Right when I get a partial sponsor my truck get's slower. I only have +100hp's according to Harvey so we'll see how well I might be able to keep up It did ok on 50hp BMS's, held 23,500 anyways on 25,000 commanded at the end.
 
Is there a part number,or any remedy to the bracket flexing,on the 2nd cp3,from this ATS kit? I had this kit on my truck(05 Dodge 2500),and the belt came off,on a high rpm run,on the highway. I've had the kit on for about 3 years. The bracket has alot of flex in it,and under high rpm,the load,put on the top cp3 pulls the pulley out of alignment. I would think there has to be a remedy by now,right?

Sent from my SM-G925V using Tapatalk
 
The mightyQuinn said:
Is there a part number,or any remedy to the bracket flexing,on the 2nd cp3,from this ATS kit? I had this kit on my truck(05 Dodge 2500),and the belt came off,on a high rpm run,on the highway. I've had the kit on for about 3 years. The bracket has alot of flex in it,and under high rpm,the load,put on the top cp3 pulls the pulley out of alignment. I would think there has to be a remedy by now,right?

Sent from my SM-G925V using Tapatalk
Click to expand...

This thread is 4 years old, I would just call ATS.
 
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