great questions!
yes you generally check dimensions on the crank recess and outer bearing carefully first then use a drive tool and oil the bearing , and seat it with a couple good whacks on the tool,there should be a .001-.003 interference fit, pack the bearing in DRY ICE for 30 minutes, before installing it and use some graphite lube powder on its outer surface before driving it into place and it usually goes in easily.
Pilot bushing clearance to trans input shaft should be .001 to .004
...with .002-.003 being considered about ideal,and the common brass pilot bearing
should be greased on install, but manufacturers parts vary and .005-.006 clearance to account for a bit of bell housing miss alignment and heat expansion is common.
to remove a pilot bearing you pack grease thru the center hole until the grease is flush with the bearings upper surface and insert a dowel into the center hole thats a loose sliding fit but will slide into the bearings inner diam. a good hard whack, on the dowel will hydraulically force the bearing out as the grease expands under the bearing, as the dowel compresses the grease as the grease can,t be compressed, and the hydraulic pressure forces the bearing up and out of the crank.
crank pilot bushings are usually removed with grease, being packed into the recess inside and behind the bearing, and having the bearing hydraulically forced out by driving in a wood or aluminum dowel to compress the grease, the grease forced to move away from the dowel, forcing the bearing out
http://www.autobarn.net/lis55500.html
THE PILOT TOOL CAN BE USED WITH GREASE AND A MALLET TO REMOVE THE OLD WORN BEARING, AS IT FITS EXACTLY
THERE ARE TOOLS TO REMOVE PILOT BEARINGS BUT THE HYDRAULIC GREASE METHOD WORKS IF YOU DON,T HAVE ONE
a bearing or seal driver , with interchangeable spacer rings ,that matches the outside diam. of the pilot bearing is usually used, to drive the new bearing into place
but IVE seen guys use a SOCKET and a hammer successfully
http://www.harborfreight.com/cpi/ctaf/d ... mber=35555
http://www.harborfreight.com/cpi/ctaf/d ... mber=95853
http://www.dormanproducts.com/p-11019-690-014.aspx
BTW its been my experience that a properly installed and lubed sintered bronze pilot bearing works better and lasts longer than the roller bearing designs, and once the recess in the cranks clean, simply packing the bronze bearing in dry ice for 30 minutes then quickly moving it with pliers and placing it in the recess and a good smack with a plastic hammer seats it easily
http://www.lislecorp.com/divisions/prod ... roduct=351
55600
Clutch Pilot Bushing Remover
Uses Hydraulic Pressure to Remove Brass and Bronze Bushings.
Screw the self-tapping tip 2-3 threads into the brass or bronze bushing. Then pump out the bushing with a grease gun. Fits brass or bronze bushings from 1/2" to 3/4" I.D. Not for use on steel bearings. Made of case hardened steel.
ok first ID point out that not all cranks are finish machined to accept a pilot bushing for a manual transmission, so its time to get out your digital calipers and check both the inside crank mounting hole diam. and the outside of the pilot bushing diam.
there are ROLLER PILOT BEARINGS, but they have a mixed reputation for durability
http://www.summitracing.com/parts/SUM-G1700/
and
SINTERED BRONZE PILOT BEARINGS
http://www.summitracing.com/parts/RAM-BU656/
now Id also point out that theres different inner pilot bearing diameters available because not all transmission spline are configured the same..bronze bushings were the standard for decades,rather than needle bearings for the transmission input shaft. Tolerances were pretty loose on this older stuff and no one disputes that the bronze bushing , if correctly installed and greased,worked fine.
you can bevel the bronze style bearings to ease installation,BUT NOT the ROLLER STYLE for what should be rather obvious reasons
the three reasons for needle bearing failure (the "new" information) seem to be 1) damaged during bearing installation, 2) damaged during transmission installation, probably due to a failure to meet contemporary bell housing run-out specs, and 3) materials incompatibility with older transmissions. Apparently modern needle bearings are bad ju-ju with 1960's transmissions regardless of tolerances. So, knowing the failure modes and avoiding them, it's probably not very risky to use a needle bearing.
http://www.harborfreight.com/blind-hole ... 95987.html
some related info here
http://forum.grumpysperformance.com/viewtopic.php?f=71&t=447&hilit=+pilot
http://chevellestuff.net/qd/crank/crank.htm
http://www.chevyhiperformance.com/t...rain/0707ch_main_bearing_clearance/index.html
viewtopic.php?f=71&t=584&p=757&hilit=+bellhousing#p757