Official Thread: Report Here if you Spun your Crank Timing Gear Hub.

[rr006rbc]

Originally Posted by sA x sKy

This HAS happened to a bone stock car. And why should it matter if BMW fixes the car modified or not? That isn't your problem.

You're a funny guy. Ask someone with this type of failure with tune and downpipes to ask his/her dealership if they'll cover his catastrophic engine failure. Please.

[Taimur]

If it's a design flaw then adding mild mods is irrelevant here.

[sA x sKy]

Originally Posted by rr006rbc

You're a funny guy. Ask someone with this type of failure with tune and downpipes to ask his/her dealership if they'll cover his catastrophic engine failure. Please.

As Taimur said, if this happens on stock cars to begin with, a tune and downpipes are irrelevant. Even the bearing problem on E9x M3's happen on stock cars. Plus, if you're getting warranty work to begin with, I would hope you take out the tune and downpipes before going into the dealer. You must not be very smart if you're going to go into the dealer with mods.

[Reid]

Originally Posted by sA x sKy

Plus, if you're getting warranty work to begin with, I would hope you take out the tune and downpipes before going into the dealer.

Even if removed, the tune leaves a bread crumb trail. Should anything catastrophic happen, the dealership will find that the car had a tune on it. This has already happened to a forum member who detonated on map 7. He removed the tune and tried to get his engine fixed under warranty. His car was red flagged.

Originally Posted by sA x sKy

You must not be very smart if you're going to go into the dealer with mods.

Since the dealership will find out anyway, it's just more honest to leave the mods on the car when it goes in for service. Don't forget that when you modify a car, you're on the hook for any damages that your modifications may cause.

Originally Posted by Taimur

If it's a design flaw then adding mild mods is irrelevant here.

Unfortunately, the people who have the early failures will commonly find the blame placed on their modifications. It's not until BMW recognizes the problem and issues a fix will this be universally covered under warranty. The first E46 M3 owners with spun rod bearings had to pay out of pocket for repairs.

[sA x sKy]

Originally Posted by Reid

Even if removed, the tune leaves a bread crumb trail. Should anything catastrophic happen, the dealership will find that the car had a tune on it. This has already happened to a forum member who detonated on map 7. He removed the tune and tried to get his engine fixed under warranty. His car was red flagged.

Since the dealership will find out anyway, it's just more honest to leave the mods on the car when it goes in for service. Don't forget that when you modify a car, you're on the hook for any damages that your modifications may cause.

That point is moot because you can remove all shadow codes with rheingold which anyone can download.

[hotrod2448]

Originally Posted by rr006rbc

Wait, what?

BMW should be fixing this car? Why do you think it should fall on BMW to foot the bill when the original horsepower and torque rating for the engine has been increased by around 60-70HP?

I would love to see a customer tow that car into the dealership demonstrating the failure with the tune and downpipes installed on it. Do please.

However, if the car is bone stock and hasn't been tampered with then of course BMW should warranty it. But it's not usually the case for people on these types of forums; catastrophic failures are mostly due to aftermarket modifications.

If it were a blown turbo, cracked ring lands, burnt piston/valves, etc... I'd totally agree with you as those are failures that could easily be attributed to tampering with the tune but, I really can't see how this failure has anything to do with power output and the mods on the car don't alter this assembly in any way shape or form. It would be akin to them trying to argue your anti-corrosion warranty is void for installing painted reflectors. This appears to be a flawed design and should be addressed by the manufacturer.

Unfortunately as Reid alluded to, I think we all know that won't stop BMWNA from trying to make the argument that it's related to the mods or abuse initially but, if stock cars start/continue to experience this issue in any significant numbers BMW will have to address it.

[CaryTheLabelGuy]

Originally Posted by hotrod2448

If it were a blown turbo, cracked ring lands, burnt piston/valves, etc... I'd totally agree with you as those are failures that could easily be attributed to tampering with the tune but, I really can't see how this failure has anything to do with power output and the mods on the car don't alter this assembly in any way shape or form. It would be akin to them trying to argue your anti-corrosion warranty is void for installing painted reflectors. This appears to be a flawed design and should be addressed by the manufacturer.

Unfortunately as Reid alluded to, I think we all know that won't stop BMWNA from trying to make the argument that it's related to the mods or abuse initially but, if stock cars start/continue to experience this issue in any significant numbers BMW will have to address it.

EXACTLY.

To my knowledge, there have been several cases of bone-stock S55s that have had this failure. Power output has little to do with this failure. It is a design flaw, plain and simple. I don't really know of any manufacturer that doesn't use a keyed or otherwise locked crank/timing gear. The reason is simple, if it slips, things will break (on an interference engine, such as most modern internal combustion engines).

BMW needs to address this. They would have a really hard time not proving they made a mistake in the design of this crank hub in a class action suit. They are basically going against industry standards by not using a keyed hub.

[M4 CSL]

Originally Posted by Reid

Even if removed, the tune leaves a bread crumb trail. Should anything catastrophic happen, the dealership will find that the car had a tune on it. This has already happened to a forum member who detonated on map 7. He removed the tune and tried to get his engine fixed under warranty. His car was red flagged.


Since the dealership will find out anyway, it's just more honest to leave the mods on the car when it goes in for service. Don't forget that when you modify a car, you're on the hook for any damages that your modifications may cause.

I thought there were no issues at all with JB4? The truth always eventually comes out. That's why.....

Honesty is always the best policy.

[hotrod2448]

Originally Posted by CaryTheLabelGuy

EXACTLY.

To my knowledge, there have been several cases of bone-stock S55s that have had this failure. Power output has little to do with this failure. It is a design flaw, plain and simple. I don't really know of any manufacturer that doesn't use a keyed or otherwise locked crank/timing gear. The reason is simple, if it slips, things will break (on an interference engine, such as most modern internal combustion engines).

BMW needs to address this. They would have a really hard time not proving they made a mistake in the design of this crank hub in a class action suit. They are basically going against industry standards by not using a keyed hub.

I'm having a hard time finding any reason for this design other than cost cutting. At first I thought it might possibly allow them to really accurately dial in the engine timing by allowing rotation of the sprocket as it's pressed onto the crank and not being locked into wherever the keyway sets it but, if you machine the parts accurately enough with a keyway style sprocket/crank and have good QC I can't see why you would need that.

[larryn]

Originally Posted by hotrod2448

I'm having a hard time finding any reason for this design other than cost cutting.

There is no cost to this at all. Indexing a part costs nothing to a supplier and to BMW. I think that if this really is a problem, that it is a design flaw on unexpected additional torque.

[hotrod2448]

Originally Posted by larryn

There is no cost to this at all. Indexing a part costs nothing to a supplier and to BMW. I think that if this really is a problem, that it is a design flaw on unexpected additional torque.

I wouldn't say no cost at all, to accurately index and add a keyway to the sprocket and crank require additional machining and qc processes. This of course adds cost, probably only a few dollars per car if that. For something as important as controlling the timing of the rotating assembly in an extremely expensive engine I would think it's worth it.

I'm guessing they thought it was a good way to simplify the parts/assembly and save a few bucks in an area no one would even care about... until they started jumping time.

[CaryTheLabelGuy]

Originally Posted by larryn

There is no cost to this at all. Indexing a part costs nothing to a supplier and to BMW. I think that if this really is a problem, that it is a design flaw on unexpected additional torque.

When you say "additional torque", what do you mean exactly? If by saying "additional torque", you're referring to a modded S55, this issue has happened on some stock S55s. The stock S55 already makes a good amount of torque. Enough to warrant a keyed crank hub. Engines with far less torque have keyed or locked timing gears. It's just common fucking sense. Otherwise, it is a ticking time bomb.

[sA x sKy]

Originally Posted by M4 CSL

I thought there were no issues at all with JB4? The truth always eventually comes out. That's why.....

Honesty is always the best policy.

Lol why the hell do you feel to sarcastically instigate? If said person detonated on map 7, most likely it was because said person did not have the fueling requirements necessary for said map.

One person detonated with the JB4 compared to how many? Go back to your corner where you came from before you try to stir up some more shit. This is about the crank hub problem, not the JB4.

[Mike@N54Tuning.com]

Originally Posted by CaryTheLabelGuy

When you say "additional torque", what do you mean exactly? If by saying "additional torque", you're referring to a modded S55, this issue has happened on some stock S55s. The stock S55 already makes a good amount of torque. Enough to warrant a keyed crank hub. Engines with far less torque have keyed or locked timing gears. It's just common fucking sense. Otherwise, it is a ticking time bomb.

Seems to me this would be related to engine acceleration not torque output and the lower the gear the faster the engine accelerates.

Mike

[hotrod2448]

Originally Posted by CaryTheLabelGuy

When you say "additional torque", what do you mean exactly? If by saying "additional torque", you're referring to a modded S55, this issue has happened on some stock S55s. The stock S55 already makes a good amount of torque. Enough to warrant a keyed crank hub. Engines with far less torque have keyed or locked timing gears. It's just common fucking sense. Otherwise, it is a ticking time bomb.

Besides that, and someone feel free to correct me if I'm wrong, the main force this sprocket sees is the torque required to drive the valve train.

So regardless of the power the engine is making as long as you aren't doing things like altering cam profiles, valve spring rate, increasing the red line or to a lesser extent possibly altering cam timing or VANOS (which I don't believe any tunes currently do) there should be no real changes in the forces seen here from stock to tuned.

[CaryTheLabelGuy]

Originally Posted by Mike@N54Tuning.com

Seems to me this would be related to engine acceleration not torque output and the lower the gear the faster the engine accelerates.

Mike

Certainly. I was just making a point. Torque has really nothing to do with this issue.

You can't make the engine rev faster in gear than you can in park or neutral. The timing gear would see more forces from a out of gear rev than an in-gear pull.

[CaryTheLabelGuy]

Originally Posted by hotrod2448

Besides that, and someone feel free to correct me if I'm wrong, the main force this sprocket sees is the torque required to drive the valve train.

So regardless of the power the engine is making as long as you aren't doing things like altering cam profiles, valve spring rate, increasing the red line or to a lesser extent possibly altering cam timing or VANOS (which I don't believe any tunes currently do) there should be no real changes in the forces seen here from stock to tuned.

You are correct. Torque has really nothing to do with this issue. See my reply above.

[TPG Tuning]

Does anyone think of load having a force on the gear? Rather than a calculated torque number based on dyno output, what is the load placed on this gear during a 4th or 5th gear dyno pull.

[TPG Tuning]

For instance , why does a clutch slip at higher tq numbers ? The force put on the gear is greater than than the torque applied from the bolt.

[CaryTheLabelGuy]

Originally Posted by TPG Tuning

For instance , why does a clutch slip at higher tq numbers ? The force put on the gear is greater than than the torque applied from the bolt.

Maybe I'm misunderstanding the point you're trying to make, but............

The force applied to the gear is greater than the clamping force from torque applied from the bolt. This is obvious. But this has nothing to do with the amount of torque the engine is exerting on a clutch.

The crankshaft is what is driving the crank hub, which has the timing gear pressed on to it, held together in place by the torque of the crank hub bolt. The timing gear drives the cam shafts via a chain. The torque from the engine IS overcoming the torque applied to the crank hub via the bolt. But what I'm saying is, the force applied to this timing gear would be just as great or greater in a neutral rev where the acceleration is much greater. The camshafts aren't providing much resistance to that timing gear, unlike the amount of resistance the drivetrain is exerting on the clutch, that the engine torque must overcome to cause the clutch to slip.

With the engine directly tied to the drivetrain (in gear pull), the crankshaft is directly connected to the wheels (as long as the clutch isn't slipping). The acceleration would be much slower on the crank hub assembly than a free rev (neutral) and thus, in mind, the forces exerted on that hub assembly would be lower.

[M4 CSL]

Originally Posted by sA x sKy

Lol why the hell do you feel to sarcastically instigate? If said person detonated on map 7, most likely it was because said person did not have the fueling requirements necessary for said map.

One person detonated with the JB4 compared to how many? Go back to your corner where you came from before you try to stir up some more shit. This is about the crank hub problem, not the JB4.

Not stirring up shit, uncovering the truth. I never made any claims about them at all. Just quoting others.

Why, because I think JB4 is at the heart of most of these issues. Where ever an issue is, you seem to find a removed JB4. Just noticing.

[Mandi90TT]

Some people you just learn to ignore.