16-03-2018, 09:17 AM
The experts will doubtless disagree but personally I would be very wary of preloaded ac races. I have done but car had an all steel housing inserted. Preload would seem to stress the lip. Bearing manuals for applications with bending, as gearbox mainshafts and semi floating hubs often recommend wide tolerance bearings.
It is difficult to establish working clearance of worn rollers. The housings are seldom truly circular. Whilst many other engines run rolling bearings the Seven seems especially sensitive to any clearance. In the 1940s/50s with “classic” oils of the time and short runs my meticulous father replaced the rear main every 2 or 3 years, 10,000 miles or less! He reckoned he could detect the difference between new one spot and two spot bearings!
Any cracks are unlikely to be obvious by eye. The last rear radius to flywheel is a major suspect. Any crank with evidence of heating there to build up is dubious. All radii should be uniform and unridged. If genuinely uncracked may be worth tidying the inner radii, even if means slight undercutting.
Loctite can hugely complicate disassembly. Brute force leads to broken lips. Thousands of Sevens went millions of miles reliably without it.
It is difficult to establish working clearance of worn rollers. The housings are seldom truly circular. Whilst many other engines run rolling bearings the Seven seems especially sensitive to any clearance. In the 1940s/50s with “classic” oils of the time and short runs my meticulous father replaced the rear main every 2 or 3 years, 10,000 miles or less! He reckoned he could detect the difference between new one spot and two spot bearings!
Any cracks are unlikely to be obvious by eye. The last rear radius to flywheel is a major suspect. Any crank with evidence of heating there to build up is dubious. All radii should be uniform and unridged. If genuinely uncracked may be worth tidying the inner radii, even if means slight undercutting.
Loctite can hugely complicate disassembly. Brute force leads to broken lips. Thousands of Sevens went millions of miles reliably without it.