Blown motors, Rod Bearing failure S65 Registry.

ssabripo wrote

I just heard pressure cookers will be banned....

Wow....speechless. You really have no heart what-so-ever.

I have pointed out what I think is the issue with the S65 "bearings" in a few threads now, but unfortunately someone at M3 post deleted posts as the discussions continued.

There is no major bearing issue with the S65. What the S65 has is oil clearances on the Main and Rod bearings that are in my opinion way too tight. For most engines there will most likely never be an issue, but, with clearances of around 0.001 there is not much room for error on assembly/during machining of the main bearing bores in the block. Basically what I am saying is that on an engine where the alignment of the main bearing bores is out even slightly or a rod has a big end that is even minutely oval shaped (either from manufacturing or by being stretched from an over-rev), there is no room for error at all. If the engine had say 0.002 which is a number that I feel should be a minimum, or even 0.0025 which the number I would like to see (TWS 10W60 is ideal to take advantage of this larger clearance since the viscosity of 60 at operating temp would lend you to believe it could handle a large oil clearance and oil pressure should not suffer) issues with the S65 main and rod "bearings" would be non existent.

So to all of you folks that think that the S65 has a rod bearing issue, that is not in any way shape of form the case, the S65 has a oil clearance issue and unless that is addressed no bearing you put into this engine will solve the problem unless the machine work is done to set the clearances to an acceptable number!

ssabripo wrote  

I just heard pressure cookers will be banned....

You're a fucking tool.

jacobe92 wrote  

BMRLVR wrote  

I have pointed out what I think is the issue with the S65 "bearings" in a few threads now, but unfortunately someone at M3 post deleted posts as the discussions continued.

There is no major bearing issue with the S65. What the S65 has is oil clearances on the Main and Rod bearings that are in my opinion way too tight. For most engines there will most likely never be an issue, but, with clearances of around 0.001 there is not much room for error on assembly/during machining of the main bearing bores in the block. Basically what I am saying is that on an engine where the alignment of the main bearing bores is out even slightly or a rod has a big end that is even minutely oval shaped (either from manufacturing or by being stretched from an over-rev), there is no room for error at all. If the engine had say 0.002 which is a number that I feel should be a minimum, or even 0.0025 which the number I would like to see (TWS 10W60 is ideal to take advantage of this larger clearance since the viscosity of 60 at operating temp would lend you to believe it could handle a large oil clearance and oil pressure should not suffer) issues with the S65 main and rod "bearings" would be non existent.

So to all of you folks that think that the S65 has a rod bearing issue, that is not in any way shape of form the case, the S65 has a oil clearance issue and unless that is addressed no bearing you put into this engine will solve the problem unless the machine work is done to set the clearances to an acceptable number!

I read your last post and it makes a whole lot of sense. I blew my 2011 M3 engine last month and I just got it back last week. Going forward I'm extremely paranoid now and is seriously considering giving up my hobby of tracking. What would you suggest I should do to my engine to prevent this from happening all over again.
Best
Roy

Was your engine replace under warranty? If it was, there is basically nothing you can do to prevent it happening again without opening up the new engine and measuring the bottom end and setting your clearances to a proper spec. This will of course void your warranty anyhow.

Your new engine may be fine and you may never have any trouble..... Only time will tell. If you want to see how the new engine is doing, take oil samples at every oil change and if there is a clearance issue, bearing material will show up on the UOA!

One thing of note to everyone, DO NOT, under any circumstances, put any excessive load on the engine until the engine oil is at operating temperature. With only about 0.001" of oil clearance and 10w60 in the crankcase, lubrication is going to be compromised until it is at operating temperature!

BMRLVR wrote

Was your engine replace under warranty? If it was, there is basically nothing you can do to prevent it happening again without opening up the new engine and measuring the bottom end and setting your clearances to a proper spec. This will of course void your warranty anyhow.

Your new engine may be fine and you may never have any trouble..... Only time will tell. If you want to see how the new engine is doing, take oil samples at every oil change and if there is a clearance issue, bearing material will show up on the UOA!

One thing of note to everyone, DO NOT, under any circumstances, put any excessive load on the engine until the engine oil is at operating temperature. With only about 0.001" of oil clearance and 10w60 in the crankcase, lubrication is going to be compromised until it is at operating temperature!

I try to be super careful with keeping the RPM's low when the oil is cold, especially with this car. Thanks for the insight.

I know you are probably under warranty, but may I ask how you feel about running other oil weights? Not to start an oil thread or anything, but would love to hear your opinion. Thanks.

W/// wrote

I try to be super careful with keeping the RPM's low when the oil is cold, especially with this car. Thanks for the insight.

I know you are probably under warranty, but may I ask how you feel about running other oil weights? Not to start an oil thread or anything, but would love to hear your opinion. Thanks.

I am toying with using a 0w40 or 5w40 after warranty........ If I do I will let the forum know beforehand!

Thx Jamie.

How low a load do you keep. I winter drive mine so I let it warm a bit but not for 10 min then I drive it.

I certainly don't drive it hard but it is prob normal acceleration.

Any way you can quantify things a bit?

sparkyg wrote  

Thx Jamie.

How low a load do you keep. I winter drive mine so I let it warm a bit but not for 10 min then I drive it.

I certainly don't drive it hard but it is prob normal acceleration.

Any way you can quantify things a bit?

I try to shift at 3k when oil is still cold

BMRLVR wrote

Was your engine replace under warranty? If it was, there is basically nothing you can do to prevent it happening again without opening up the new engine and measuring the bottom end and setting your clearances to a proper spec. This will of course void your warranty anyhow.

Your new engine may be fine and you may never have any trouble..... Only time will tell. If you want to see how the new engine is doing, take oil samples at every oil change and if there is a clearance issue, bearing material will show up on the UOA!

One thing of note to everyone, DO NOT, under any circumstances, put any excessive load on the engine until the engine oil is at operating temperature. With only about 0.001" of oil clearance and 10w60 in the crankcase, lubrication is going to be compromised until it is at operating temperature!

I am extremely careful when the engine is cold and try and stay below 3k rpm just for the peace of mind. Also with BPM Stage I incorporating 4k rpm limit when cold the chances of any damage is somewhat minimized at the hand of an idiot workshop boy at the stealership.

But given all these issues, surely BMW should build in some tolerance in this area given after all everyone one is human and can overlook this unintentionally.

I sometimes wonder if the BMW engine was really designed with a thinner grade oil from the start with the tight tolerance that BMRLVR pointed out. Then another BMW department decided to market and use the 10-60w for the prolonged 15k oil change interval. Would really like to know about the use of thinner oil, especially for some of us that change the oil at 5k or 7.5k.

W/// wrote

I try to shift at 3k when oil is still cold

Have been doing that for a few years man,I'm at 82,000 miles and running great.no engine malfunctions

sparkyg wrote

Thx Jamie.

How low a load do you keep. I winter drive mine so I let it warm a bit but not for 10 min then I drive it.

I certainly don't drive it hard but it is prob normal acceleration.

Any way you can quantify things a bit?

W/// wrote

I try to shift at 3k when oil is still cold

It is less about the RPM you shift at than the percentage of throttle opening! I try to never use more than 25% throttle until the engine is at operating temperature. 50% - 100% throttle, but still shifting at low RPM's will hurt the engine just as much as spinning it 7 or 8K cold at low throttle openings. I too keep RPMs below 3-4K but I mainly concentrate on not applying too much throttle till the oil is up to temp!

e92zero wrote

I sometimes wonder if the BMW engine was really designed with a thinner grade oil from the start with the tight tolerance that BMRLVR pointed out. Then another BMW department decided to market and use the 10-60w for the prolonged 15k oil change interval. Would really like to know about the use of thinner oil, especially for some of us that change the oil at 5k or 7.5k.

The Grade of oil means less to the OCI than the base oil stability and the additive pack. With that being said, I think they use this oil to protect engines at HIGH temperatures, read track usage. For mainly street driven cars this 10W60 is overkill IMO. The 10W60 shines at oil temps above 120C (250F) not going to get groceries or cruising down the highway at 100KM/h (65MPH) where the oil temp never makes 100C (212F).

BMRLVR wrote

It is less about the RPM you shift at than the percentage of throttle opening! I try to never use more than 25% throttle until the engine is at operating temperature. 50% - 100% throttle, but still shifting at low RPM's will hurt the engine just as much as spinning it 7 or 8K cold at low throttle openings.

Why is the throttle position that important at low RPM when the engine isn't spinning quickly and the stress levels are low?

BMRLVR wrote

The Grade of oil means less to the OCI than the base oil stability and the additive pack. With that being said, I think they use this oil to protect engines at HIGH temperatures, read track usage. For mainly street driven cars this 10W60 is overkill IMO. The 10W60 shines at oil temps above 120C (250F) not going to get groceries or cruising down the highway at 100KM/h (65MPH) where the oil temp never makes 100C (212F).

Thanks.

So back to the topic "bearing failure S65 registry". How many have registered with failures here in this 7 pages?

Dodge2Dub wrote  

BMRLVR wrote

It is less about the RPM you shift at than the percentage of throttle opening! I try to never use more than 25% throttle until the engine is at operating temperature. 50% - 100% throttle, but still shifting at low RPM's will hurt the engine just as much as spinning it 7 or 8K cold at low throttle openings.

Why is the throttle position that important at low RPM when the engine isn't spinning quickly and the stress levels are low?

Engine speed is an issue, but load is also an issue. High load puts more stress on the bearings since higher throttle openings cause the engine to make more torque. More torque = higher BMEP. Higher BMEP = more force exerted on the pistons, rods, crank and ultimately the bearings. When the engine is not at operating temperature the hydrodynamic lubrication in the bearing is not fully developed so you can have metal on metal contact!

BMRLVR wrote

Engine speed is an issue, but load is also an issue. High load puts more stress on the bearings since higher throttle openings cause the engine to make more torque. More torque = higher BMEP. Higher BMEP = more force exerted on the pistons, rods, crank and ultimately the bearings. When the engine is not at operating temperature the hydrodynamic lubrication in the bearing is not fully developed so you can have metal on metal contact!

Thx jamie.

Sorry it was OT.

On again with bearing failures....

BMRLVR wrote

Engine speed is an issue, but load is also an issue. High load puts more stress on the bearings since higher throttle openings cause the engine to make more torque. More torque = higher BMEP. Higher BMEP = more force exerted on the pistons, rods, crank and ultimately the bearings. When the engine is not at operating temperature the hydrodynamic lubrication in the bearing is not fully developed so you can have metal on metal contact!

Thanks for the reply...I learn something every day!

1MtoM3 wrote

I cant wait to SC this bad boy and have it blow its engine in two or three or never years , and then lose three months of sleep afterwards wondering if it was the build quality, the SC or Jesus !!!!
You only live once . It's a pile of nuts and bolts like a plane or a lawnmower,both of witch will fail eventually.

lol

If the oil clearance is set to .002 what modifications to the oil system would you recommend? The pressure stock is typicaly 40psi at idle and jumps to 80 psi at 2000 rpm. When the clearances are set to .002 it changes to 20-25 psi up to 2000 rpm then to 60 psi. Just curious how this would affect the daily driver type that will see below 2000 rpm frequently. I do appreciate your input.

BMRLVR wrote

I am toying with using a 0w40 or 5w40 after warranty........ If I do I will let the forum know beforehand!

VCMpower wrote

If the oil clearance is set to .002 what modifications to the oil system would you recommend? The pressure stock is typicaly 40psi at idle and jumps to 80 psi at 2000 rpm. When the clearances are set to .002 it changes to 20-25 psi up to 2000 rpm then to 60 psi. Just curious how this would affect the daily driver type that will see below 2000 rpm frequently. I do appreciate your input.

Generally speaking, oil pressure does drop as oil clearance increases hence the reason why engines lose oil pressure if main and/or rod bearings are worn excessively.

20-25 PSI is lots of oil pressure at idle (40 PSI actually a fairly high number at idle) if that is even the number that the S65 engine would have at .002". I have never seen anyone test the oil pressure on an S65 with .002" main bearing clearance but would look forward to the numbers. As for your maximum pressure, that is going to be set by the system relief valve......... if the relief is at 80 PSI, once the pump makes enough flow to go over relief it will still achieve that same 80 PSI that you state, it may just take a few more RPM to get there........ the principles of hydraulics are universal pressure is the resistance to flow and more flow equals more pressure. Flow increases as the oil pump RPM increases(oil pump speed is tied directly to engine RPM) which is why there has to be a system relief to protect the system from overpressure since the oiling system on the S65 uses a positive displacement pump.

FYI: Dinan sets the main bearings to .0019" and the rods to .0025" on their strokers....... I obtained this information while shopping for a stroker! Obviously they see an issue with the tight OEM clearances and they don't see an oil pressure issue with adding a bit of clearance to the Mains and Rods since they use an OEM oil pump!

Thanks. I do know of a LC motor that has been set to .002 and those are real specs I gave you. So you have a little more info if you wish to take it. It does not reach above 60 psi at that clearance. This is why I was curious if you were thinking a dry sump setup where you can achive different pressure/flow. Taking another S65 apart on Monday so I will let ya know what clearances are there and condition of bearings. It is a 2008. That is quite amazing if that is all Dinan is doing and maintaing pressure. If I remember correct BMW provided thinner shells for the S54 and a larger volume oil pump.

BMRLVR wrote

Generally speaking, oil clearance does drop as oil clearance increases hence that is the reason why engines lose oil pressure if main and/or rod bearings are worn excessively.

20-25 PSI is lots of oil pressure at idle (40 PSI actually a fairly high number at idle) if that is even the number that the S65 engine would have at .002". I have never seen anyone test the oil pressure on an S65 with .002" main bearing clearance but would look forward to the numbers. As for your maximum pressure, that is going to be set by the system relief valve......... if the relief is at 80 PSI, once the pump makes enough flow to go over relief it will still achieve that same 80 PSI that you state, it may just take a few more RPM to get there........ the principles of hydraulics are universal pressure is the resistance to flow and more flow equals more pressure. Flow increases as the oil pump RPM increases(oil pump speed is tied directly to engine RPM) which is why there has to be a system relief to protect the system from overpressure since the oiling system on the S65 uses a positive displacement pump.

FYI: Dinan sets the main bearings to .0019" and the rods to .0025" on their strokers....... I obtained this information while shopping for a stroker! Obviously they see an issue with the tight OEM clearances and they don't see an oil pressure issue with adding a bit of clearance to the Mains and Rods since they use an OEM oil pump!