A question about rod bearing dimensions
09-05-2009, 08:24 PM
#1
Nordschleife Master
Thread Starter
A question about rod bearing dimensions
Does anyone have the standard rod bearing dimensions?
Here's what I "know" from the WSM: The crankshaft rod journal diameter is 51.971 mm - 51.990 mm. Radial play between journal and bearing is 0.034 mm - 0.092 mm, although it seems that this may vary from model year to model year. And the way I do tolerance math is that the bearing ID would have to be 52.024 mm - 52.063mm for the 51.971 mm - 51.990 mm cranks always to produce 0.034 mm - 0.092 mm. But that's just a conjecture.
What I don't know are the basic dimensions of the standard size rod bearing.
(1) How wide (some people would call this overall length) is the bearing? I can't find this on FM/Glyco web site, anywhere else on the web, or in the WSM. It's very basic number and I think it could just be measured if someone has a bearing at hand.
(2) What are the min/max ID of the standard rod bearing? Basically, I am looking for the spec, not a measurement. Again, no luck with the WSM or with google.
(3) Can someone please confirm that the big end bore diameter where the bearing is seated is 54.991 mm, which is presumably the crushed bearing OD as well? I am assuming that this is measured with the rod bolts torqued to spec. Also, what's the manufacturing tolerance there?
Even partial answers appreciated.
Here's what I "know" from the WSM: The crankshaft rod journal diameter is 51.971 mm - 51.990 mm. Radial play between journal and bearing is 0.034 mm - 0.092 mm, although it seems that this may vary from model year to model year. And the way I do tolerance math is that the bearing ID would have to be 52.024 mm - 52.063mm for the 51.971 mm - 51.990 mm cranks always to produce 0.034 mm - 0.092 mm. But that's just a conjecture.
What I don't know are the basic dimensions of the standard size rod bearing.
(1) How wide (some people would call this overall length) is the bearing? I can't find this on FM/Glyco web site, anywhere else on the web, or in the WSM. It's very basic number and I think it could just be measured if someone has a bearing at hand.
(2) What are the min/max ID of the standard rod bearing? Basically, I am looking for the spec, not a measurement. Again, no luck with the WSM or with google.
(3) Can someone please confirm that the big end bore diameter where the bearing is seated is 54.991 mm, which is presumably the crushed bearing OD as well? I am assuming that this is measured with the rod bolts torqued to spec. Also, what's the manufacturing tolerance there?
Even partial answers appreciated.
