Actually yes, many of the oversize bearings out there use an oversize thrust.
(This is the logical way to deal with a crank with a worn thrust surface,
right?)
If the bearings are correct in every other way (just like the old one's,
correct diameter, oil holes in the right spot, etc)-they are probably
correct. Check with your vendor.
Some manufacturer's thrust surface looks identical to the bearing surface
(not copper color). The center bearing does have 2 integral thrust surfaces,
(not separate thrust bearings) yes?
Assuming they are correct, you need to place the thrust in the journal,
measure the face-face dimension and have the crank surface machined
for correct clearance. (.001-0035 off the top of my head.)
Jim Tyler
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From: Mark Ruffcorn[SMTP:mruffcorn@ksni.net]
Sent: Saturday, April 24, 1999 11:54 PM
To: datsun-roadsters@autox.team.net
Subject: Fw: Boy am I "cranky"!
Looking for some insight tonight!
I was putting my motor back together tonight (U20)and hit a snag right off.
While sliding in the crank, the thrust bearing was to wide to fit between
the journals. The bearings are .030 over (.75) and the crank has been
machined to the same specs. Also the thrust bearings did not have babbet on
the sides. Is this normal for the U20?
I spec'ed it out with the micrometer and found there is NO clearance!? Do
they normally grind the crank for side clearance on the thrust bearing
journal on these engines? I purchased the parts from one of the lists
"prefered" suppliers(NDC is the brand name of the bearings). Did I get a
defective part?
This is my vacation week and was to be devoted solely to getting this and
other roadster related tasks accomplished. :-( Help! Any expertise in
the near future would be GREATLY appreciated. (Still hoping to get it back
together later in the week if I can determine and fix the problem)
Thanks
Nathan (In dire need)
69 2000 probabaly run ok for a WHILE without the thrust bearing RIGHT? :-)
70 1600 (still installing the top this week-especialy with all the
"spare" time I'll have waiting on parts or machine shop!)
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