#2 bearing on stroker motor
02-26-2014, 03:09 PM
#1
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#2 bearing on stroker motor
Does the #2 bearing suffer the same fate with a 3.0l crank compared to the 2.5l? Was wondering if maybe the more modern design 3.0l crank helped in this matter.
Cheers,
Dwane
Cheers,
Dwane
02-26-2014, 09:36 PM
#2
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02-28-2014, 01:20 PM
#4
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The 3L crank design is not much different than the 2.5L crank, except for the stroke.
When the 3L crank is used in the 2.5L block to create a 2.8L stroker, then the #2 bearing is more of a problem.
The longer stroke there is more air (than a 2.5L shorter stroke) is being pushed behind the piston toward the crankcase when the piston is traveling to BDC.
At the same time, the adjacent piston is creating more vacuum on its way to TDC.
This process (windage) creates additional oil problems in the crankcase which does not help the #2 rod bearing failure. (There are other contributing factors).
The windage issue was addressed by the factory in the 3L block. The 3L block has windage holes at the bottom of the cylinders, between #1 & #2 and #3 and #4. These holes tend to somewhat equalize the air movement between the cylinders before they reach the crankcase.
Of course, the 3L block can and does suffer from #3 bearing failures..
BTW #2 is the most failed rod bearing, but other cylinders can have a problem as well, just not as frequent.
When the 3L crank is used in the 2.5L block to create a 2.8L stroker, then the #2 bearing is more of a problem.
The longer stroke there is more air (than a 2.5L shorter stroke) is being pushed behind the piston toward the crankcase when the piston is traveling to BDC.
At the same time, the adjacent piston is creating more vacuum on its way to TDC.
This process (windage) creates additional oil problems in the crankcase which does not help the #2 rod bearing failure. (There are other contributing factors).
The windage issue was addressed by the factory in the 3L block. The 3L block has windage holes at the bottom of the cylinders, between #1 & #2 and #3 and #4. These holes tend to somewhat equalize the air movement between the cylinders before they reach the crankcase.
Of course, the 3L block can and does suffer from #3 bearing failures..
BTW #2 is the most failed rod bearing, but other cylinders can have a problem as well, just not as frequent.
02-28-2014, 01:24 PM
#5
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The 3L crank design is not much different than the 2.5L crank, except for the stroke.
When the 3L crank is used in the 2.5L block to create a 2.8L stroker, then the #2 bearing is more of a problem.
The longer stroke there is more air (than a 2.5L shorter stroke) is being pushed behind the piston toward the crankcase when the piston is traveling to BDC.
At the same time, the adjacent piston is creating more vacuum on its way to TDC.
This process (windage) creates additional oil problems in the crankcase which does not help the #2 rod bearing failure. (There are other contributing factors).
The windage issue was addressed by the factory in the 3L block. The 3L block has windage holes at the bottom of the cylinders, between #1 & #2 and #3 and #4. These holes tend to somewhat equalize the air movement between the cylinders before they reach the crankcase.
Of course, the 3L block can and does suffer from #3 bearing failures..
BTW #2 is the most failed rod bearing, but other cylinders can have a problem as well, just not as frequent.
When the 3L crank is used in the 2.5L block to create a 2.8L stroker, then the #2 bearing is more of a problem.
The longer stroke there is more air (than a 2.5L shorter stroke) is being pushed behind the piston toward the crankcase when the piston is traveling to BDC.
At the same time, the adjacent piston is creating more vacuum on its way to TDC.
This process (windage) creates additional oil problems in the crankcase which does not help the #2 rod bearing failure. (There are other contributing factors).
The windage issue was addressed by the factory in the 3L block. The 3L block has windage holes at the bottom of the cylinders, between #1 & #2 and #3 and #4. These holes tend to somewhat equalize the air movement between the cylinders before they reach the crankcase.
Of course, the 3L block can and does suffer from #3 bearing failures..
BTW #2 is the most failed rod bearing, but other cylinders can have a problem as well, just not as frequent.
02-28-2014, 01:39 PM
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02-28-2014, 02:11 PM
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