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auskip07 said:
So whats the easiest way? install bearings on each half and then the shaft 1 side at a time?
Click to expand...
Installing crankshaft bearings in a pro split case saw is fairly easy if you know the secret. Once you get the crank, seals and old bearings out the re-assembly is actually easier. Take your new bearings and the crankshaft put them in a plastic bag and toss them in the freezer for a few hours, even better if overnight. This freezing them contracts them, makes them smaller. Cold = contract, heat = expand. When your ready to install the new bearings heat up the crankcase half your doing first to 280 degrees. Once you reach that temp on the case half have the ice cold bearing for that half near by and it will drop right into place. Do the same for the other half. Now you let them sit. The case halves cool off and the frozen bearings heat up. You get a nice tight fit, bearing job is done. The frozen crankshaft will slip fairly easy into the bearings to a point, tap the rest of the way in with a mallet. Don't forget the crankcase gasket when putting the halves together. Once its all back together check the tightness of the crank rotation. Should turn freely, if not tight tap the end of the crank with a mallet until you can spin it easy. Job done, time taken, maybe 30 minutes at most. I taught this lesson to Fish before he passed away from the site, wink!!!
 
Common sense that we all know.......that you try to throw a monkey wrench in to try to discredit those that actually know more than you......i give you interference fit from the NMB website oh wait from uh.......all the other ball bearing websites dude! They dont say anything about taper or keys.
When a ball bearing is used, it is not used alone. It is likely to be used on a shaft or in a housing bore by an Interference Fit. The Interference Fit is described as a value of tightness between the shaft and bearing bore or the housing bore and bearing outside diameter. The three main types of interference fits are distinguished as Loose Fit, Light Interference Fit and Interference Fit. As subject of the Fit, the purpose is to prevent creeping. Once creeping occurs, the temperature will be abnormally generated by the slipping abrasion. Creeping is associated with the slipping between fitted surfaces. It will be a cause of premature life failure or that the abrasion particles will enter the bearing and cause it to become noisy and eventually burn up. Typically a large interference fit prevents creeping, but it is necessary to select the interference fit by giving attention to the reduction of radial clearance (negative clearance), the temperature distribution during the bearing operation (the change of the interference fit by temperature) and the influence to the raceways. More details about what interference fits are, how creeping works, and how interference fits and creeping are related are provided below. The following formula sets up a standard to calculate how much radial clearance is reduced when a bearing is pressed onto a shaft or into a housing.
 
Text book from my power transmission class. I am in an apprenticeship program to become a journeyman general mechanic
 
jughead500 said:
Common sense that we all know.......that you try to throw a monkey wrench in to try to discredit those that actually know more than you......i give you interference fit from the NMB website oh wait from uh.......all the other ball bearing websites dude! They dont say anything about taper or keys.
When a ball bearing is used, it is not used alone. It is likely to be used on a shaft or in a housing bore by an Interference Fit. The Interference Fit is described as a value of tightness between the shaft and bearing bore or the housing bore and bearing outside diameter. The three main types of interference fits are distinguished as Loose Fit, Light Interference Fit and Interference Fit. As subject of the Fit, the purpose is to prevent creeping. Once creeping occurs, the temperature will be abnormally generated by the slipping abrasion. Creeping is associated with the slipping between fitted surfaces. It will be a cause of premature life failure or that the abrasion particles will enter the bearing and cause it to become noisy and eventually burn up. Typically a large interference fit prevents creeping, but it is necessary to select the interference fit by giving attention to the reduction of radial clearance (negative clearance), the temperature distribution during the bearing operation (the change of the interference fit by temperature) and the influence to the raceways. More details about what interference fits are, how creeping works, and how interference fits and creeping are related are provided below. The following formula sets up a standard to calculate how much radial clearance is reduced when a bearing is pressed onto a shaft or into a housing.
Click to expand...
Ok
HarleyT said:
Bull **** Tommy!!!! You going to let these kids bring us both back, are you????? You double bar nut!!!!
Click to expand...
Dude I know what you are trying to do . Ruin the site because you have a beef .
 
HarleyT said:
Bull **** Tommy!!!! You going to let these kids bring us both back, are you????? You double bar nut!!!!
Click to expand...
Who be you there stranger? Double bar nut isn't the best way to replace the bar stud BUT it can be done, I got a va diddy o to prove it somewhere. This talk of crank bearing misery is silly, its actually easy if you got a freezer in the shop where you keep your Pepsi's nice and cold in the bottom and your ice cream in the freezer department when you must take a break 10-15 times a day like I do, oppps, I mean some do,hehe
 
Actually if installing bearings in the cases you want you bearings at room temperature. I've found that if heating the case at 275 degrees and dropping the bearing in it cools the case down before the bearing has a chance to get all of the way down to where it needs to be.room temperature does better for me.
Hardlyt 3..2...1
 
Any moron knows about tapping cold bearings into place. No one said much about the taper, or whatever, but who give a ****...

You have to promise to stick around here, you knothead!!!!!! Hell, Llamabert is back, this site is in some serious need for
some action!!!!!!
 
jughead500 said:
Actually if installing bearings in the cases you want you bearings at room temperature. I've found that if heating the case at 275 degrees and dropping the bearing in it cools the case down before the bearing has a chance to get all of the way down to where it needs to be.room temperature does better for me.
Hardlyt 3..2...1
Click to expand...
Never had that problem but you make a valid point there. All the ones I've installed bottom out, they fall in place but your correct, the cold bearing would cool the case half faster. Room temp with a hot case half would probably work too. I've seen people pound bearings in and it always worried me the case half might crack but low and behold I've yet to see one crack..
 

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