Denny
1954 (
and in at least 1955-2nd series) engines
used shims for adjusting main bearing clearance. However,
shims were not used to adjust rod bearing clearance on 1954 (and 1955-1st) engines.
The 1956 Truck Shop Manual states (sect. 6.2,):
MAIN BEARINGS
.
.
The adjustment of shims formerly used between the bearing cap and cylinder block have [sic]
also been discontinued.
.
.The statements above (and in my earlier post) are from Chevrolet Truck Shop Manuals. I have no doubt that many shops used shims even when a Shop Manual stated they were not necessary. Many shops also filed bearing caps, even though the Ship Manuals clearly warn against doing this.
The engine in question at the start of this post is a 1958 or later engine.
