Sanding/scotch brite to increase bearing clearance?
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Re: Sanding/scotch brite to increase bearing clearance?
Can't you just pour some lapping compound on the halves, drop in the crank, torque the mains and spin the crank a few times? Clearance Clarence!
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Re: Sanding/scotch brite to increase bearing clearance?
You have to make sure the line bore is within .000002" and size the lapping granules as some may be a bit large. Then grab a cold one as the drill turns the crank then come back when the cold ones ware off and make sure you did not go .020"mystic1582 wrote: Can't you just pour some lapping compound on the halves, drop in the crank, torque the mains and spin the crank a few times? Clearance Clarence!
I love the internet!!! You guys crack me up!! I know you were joking by the way.....
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Re: Sanding/scotch brite to increase bearing clearance?
my local machine shop owner told me to scotch brite the bearings in my ford 2300 4 cyl. with a fine grit pad. I did and ran the engine for two years and the bearings look good when I tore down the bootm end. i ran a high pressure oil pump(90 cold-60 hot) 5 qts Castrol 20w-50 plus a quart of lucas oil treatment. Changed oil every two weeks. I could have used the bearings again they looked that good! So scotch briteing does work.
I thought I was wrong once but I was mistaken...
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Re: Sanding/scotch brite to increase bearing clearance?
af2 wrote:You have to make sure the line bore is within .000002" and size the lapping granules as some may be a bit large. Then grab a cold one as the drill turns the crank then come back when the cold ones ware off and make sure you did not go .020"mystic1582 wrote: Can't you just pour some lapping compound on the halves, drop in the crank, torque the mains and spin the crank a few times? Clearance Clarence!
I love the internet!!! You guys crack me up!! I know you were joking by the way.....
Re: Sanding/scotch brite to increase bearing clearance?
You know it cracks me up. The manufacturer of the bearings spend millions of dollars in research to find the best surface for the bearing. Some hack decides he is going to out wit them and do some bearing suface conditioning...
Bill McNight (clevite) in his bearing seminars says it's ok to hit the surface with newspaper and thats it.
Keith
Bill McNight (clevite) in his bearing seminars says it's ok to hit the surface with newspaper and thats it.
Keith
“If I hit you with this you’re going to be numb, that’s why they call them numb-chucks “Si Robertson
Re: Sanding/scotch brite to increase bearing clearance?
Just install these. No need to check anything, they'll take care of themselves.
"These Sealed Power A-Series rod bearings can actually polish the journals on your crankshaft. That's because there is a small percentage of silicon mixed in with the aluminum and tin that make up the bearing-surface alloy. The silicon is there for wear resistance, but its toughness actually smoothes the journals of a crank with a surface that hasn't been optimized! This special surface alloy is laid over a high-strength 1010 steel backing and delivers improved seizure and corrosion resistance, as well as better wall variance control. It also helps to minimize debris embedding, which can score the crank's surface."
"These Sealed Power A-Series rod bearings can actually polish the journals on your crankshaft. That's because there is a small percentage of silicon mixed in with the aluminum and tin that make up the bearing-surface alloy. The silicon is there for wear resistance, but its toughness actually smoothes the journals of a crank with a surface that hasn't been optimized! This special surface alloy is laid over a high-strength 1010 steel backing and delivers improved seizure and corrosion resistance, as well as better wall variance control. It also helps to minimize debris embedding, which can score the crank's surface."
Re: Sanding/scotch brite to increase bearing clearance?
robert1 wrote:Just install these. No need to check anything, they'll take care of themselves.
"These Sealed Power A-Series rod bearings can actually polish the journals on your crankshaft. That's because there is a small percentage of silicon mixed in with the aluminum and tin that make up the bearing-surface alloy. The silicon is there for wear resistance, but its toughness actually smoothes the journals of a crank with a surface that hasn't been optimized! This special surface alloy is laid over a high-strength 1010 steel backing and delivers improved seizure and corrosion resistance, as well as better wall variance control. It also helps to minimize debris embedding, which can score the crank's surface."
This is Sarcasm, right???
“If I hit you with this you’re going to be numb, that’s why they call them numb-chucks “Si Robertson
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Re: Sanding/scotch brite to increase bearing clearance?
Greenlight wrote:You can try:
Option 1:
Bring the crank to a local crank grinder and have them polish the journals. They can remove from 0.0001" to 0.0015" from the journals. If you let them know how much smaller you want the journals they can usually get the crank within 0.0003" or so of what you want. Then you can use standard bearings and get the required clearance.
I've done both.
You will never polish a crank to the proper size and have the jounal flat.
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Re: Sanding/scotch brite to increase bearing clearance?
k-star wrote:robert1 wrote:Just install these. No need to check anything, they'll take care of themselves.
"These Sealed Power A-Series rod bearings can actually polish the journals on your crankshaft. That's because there is a small percentage of silicon mixed in with the aluminum and tin that make up the bearing-surface alloy. The silicon is there for wear resistance, but its toughness actually smoothes the journals of a crank with a surface that hasn't been optimized! This special surface alloy is laid over a high-strength 1010 steel backing and delivers improved seizure and corrosion resistance, as well as better wall variance control. It also helps to minimize debris embedding, which can score the crank's surface."
This is Sarcasm, right???
I can't believe they advertise and sell these. That is a direct quote.
Re: Sanding/scotch brite to increase bearing clearance?
CNC BLOCKS wrote:Greenlight wrote:You can try:
Option 1:
Bring the crank to a local crank grinder and have them polish the journals. They can remove from 0.0001" to 0.0015" from the journals. If you let them know how much smaller you want the journals they can usually get the crank within 0.0003" or so of what you want. Then you can use standard bearings and get the required clearance.
I've done both.
You will never polish a crank to the proper size and have the jounal flat.
X2 X2 X2
Gov
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Re: Sanding/scotch brite to increase bearing clearance?
Happy news story or sad news story? The gritty news is hard on the journal, a nice 'girl saves a duck in the park' story gives a nicer crank finish..k-star wrote:You know it cracks me up. The manufacturer of the bearings spend millions of dollars in research to find the best surface for the bearing. Some hack decides he is going to out wit them and do some bearing suface conditioning...
Bill McNight (clevite) in his bearing seminars says it's ok to hit the surface with newspaper and thats it.
Keith
Grind the crank or change the bearings, It works really well.!!
Craig.
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Re: Sanding/scotch brite to increase bearing clearance?
Your first sentence is pretty much verbatim of what I wrote in my letter to the editor of Popular Hot Rodding.k-star wrote:You know it cracks me up. The manufacturer of the bearings spend millions of dollars in research to find the best surface for the bearing. Some hack decides he is going to out wit them and do some bearing surface conditioning...
Bill McNight (clevite) in his bearing seminars says it's ok to hit the surface with newspaper and thats it.
Keith
tom
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We used to speak to tell things , now they tell things to speak.
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Re: Sanding/scotch brite to increase bearing clearance?
C'mon guys , just put a fine sandpaper stripe between the crank journal and bearing....turn it a couple times while tighten the caps in 1lbs increments.
Works flawlesly, everytime.
Works flawlesly, everytime.
'71 Z28 street strip car
Pump gas All motor SBC 427
3308 lbs-29x10.5 Hoosiers
NEW BEST ET
1.38 60' / 4.05 330' / 6.32@111.25mph
https://www.youtube.com/watch?v=99p13UK ... ture=share
Pump gas All motor SBC 427
3308 lbs-29x10.5 Hoosiers
NEW BEST ET
1.38 60' / 4.05 330' / 6.32@111.25mph
https://www.youtube.com/watch?v=99p13UK ... ture=share
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Re: Sanding/scotch brite to increase bearing clearance?
Here is my thoughts on crank grinding, I grind to the desired size and only polish for appearance and looks. You can't polish to remove material and expect to keep the journal profile simple as that. Try balance an eagle crank and keep the belt in the middle of the main, tough deal because they usually have the heck polished outa them and the middle of the journal is smaller than the sides.
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Re: Sanding/scotch brite to increase bearing clearance?
BrazilianZ28Camaro wrote:C'mon guys , just put a fine sandpaper stripe between the crank journal and bearing....turn it a couple times while tighten the caps in 1lbs increments.
Works flawlesly, everytime.
now thats what I call custom fitting !!
Craig.