15 hp johnson crankshaft ball bearing

[mekkamaz]

Hello friends! A little question here.........The ball bearing of the crankshaft seems ok, but as this is an older motor ('82), I?m thinking in replace it with a new one. Before I order one, I have in my hand a *** 6204 TB P6 C3, that is a polyamide cage fiberglass reinforced. The original bearing has the numbers faded, but I know it is also a 6204 something..anyone can say if this is the same bearing?? or it is other cage material??


J15RCNC...

thanks !!

 

[orbanp]

Re: 15 hp johnson crankshaft ball bearing

That bearing is fine for you, go ahead and use it.

- The number is the same, the diameters are the same.
- TB means machined textile laminated phenolic cage, guidance by the inner ring. These cages are used for high speed operation, so it should be fine for you. Above 120 C degrees phenolic cages usually age faster. The temperature in the crankcase is around 60 - 80 C degrees.
- P6 is a higher accuracy class bearing. Bearings have about five or six accuracy classes, this one is the second from the bottom.
- C3 bearings have a looser internal clearance and are usually specified for hot running devices. C3 bearings have additional internal radial clearances to allow for expansion in high speed / temperature environments. Typically suited to hot and high speed environments (fans, high speed motors etc). They can feel loose until at running temperature and speed.

In short, this is a more expensive bearing, but should work fine for your application.

Peter

 

[mekkamaz]

Re: 15 hp johnson crankshaft ball bearing

Thank you very much, Peter. _I ?ve searched the web and only find that bearing marked as a competition for bikes.....but thanks again for the excellent info. You?ve made my day!!! also I?m very thankful to you for sharing all this info.
Oscar.