PN for HD ball roller main on timing side

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Looking for a PN for the so called heavy duty version. What exactly makes it "heavy duty" compared to the stock, steel cage factory one?
 
What engine are you asking about? The timing and drive side of commando engines take the "SuperBlend Roller Bearings", 06.4118. Or are you not asking about an engine?
 
Looking for a PN for the so called heavy duty version. What exactly makes it "heavy duty" compared to the stock, steel cage factory one?
Chris,

if I recall correctly, it was called a "max load" bearing, and the heavy duty part was that it had one more ball than the stock bearing. I think it had a notch in the side of the races that let them add another ball during assembly. But that was decades ago, and my memory isn't as reliable as it used to be. I'll look through my notes at the time, and see if I wrote anything down.

Ken
 
Ken,
Yes, I am talking about that one. The improved replacement for the 8 ball, steel cage R&M MJ30 bearing which was installed in just about every pre'72 engine on the timing side.
 
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I found some of my old notes. The replacement I used was a 10 ball unit. I don't recall which brand I used, but a current part number would be a Timpken 306W. The visual difference with the normal and max load bearings is the presence of a loading slot in the races of the max load type that allows inserting an extra (or sometimes two extra) ball for higher load capacity.

Ken
 
Thank you all for the info & links. It was good, rainy-day reading for such weather as we had yesterday, and we don't get those here too often.

I do prefer the timing side ball bearing because of the axial side loading from the crank nut torque pulling the crankshaft tight, and the oil pump. I did not really see this mentioned in the links but maybe I missed it.

But I do not like having to heat the case to get the crank out on teardown, and the chance for the ball bearing to bind when coming out if the case if the timing side case isn't supported 100% straight vertical.

I have many FAG roller bearings here, new, used, NOS, India, Germany etc. All inner races seem good and tight on the early cranks which I see were machined different than later cranks.

I have written off most of JM Leadbeater's beloved R&M rollers because I believe FAG Schaeffler to be a higher-quality manufacturer.
 
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