VCCA Home Forums GENERAL DISCUSSION New User Forum 216 bolt torque and crank machining

My Motors manual says the main bolt torque is 100 foot lbs.I see that the rear brg housing has 4 smaller diameter bolts and some have stretched.Should these be also 100 foot lbs?
I am over hauling the engine ( meaning cleaning out the dirt and looking for better parts from our only scrapyard ).The machine shop hasn't seen a crank without any holes in and doesn't want to machine it.What size should he machine to? The manual says shims were fitted but what size did the factory machine to to add so many shims? Would size for size do and I add shims as required? I found a standard size second hand crank with the usual big end wear.

All of the main bearing bolts were to be tightened to 100 foot pounds. If the rear bolts were over tightened at one time and stretched I would advise replacing them. Other than that I would think 80 pounds would be sufficent.
The factory installed four shims on each side. As the crank or bearings wore down shims could be removed to adjust the bearing clearance. If the crank is turned to an undersize, undersized bearings must be used. They came in .010", .020" and .30" undersizes.
The above would depend on the year of the 216.

1937 - 1947 was Babbit bearings, 1948 - 1953? was insert bearings. Right Geno?

If you are refering to the main bearings ALL had babbit bearings. The babbit was thinner on the 1948 and up and in 1948 they used precision main earings which meant just one bearing could be replaced if necessary. Also the main bearings did not require line boring. After 1948 the 1947 and prior main bearings sold through parts were of the precision type and for an initial replacement all four had to be replaced.
The rods were alll babbited with the thicker babbit used through 1947 and the thin babbit used in 1948 and up. The 1948 and up rod journals were also slightly narrorer.
The trend to thinner babbit was tking place for alll engines in the '40's.

What was the final year for the 216" and babbits? I had heard once, that South of the Border down Mexico way, they were still using 216" well into the 50's

The 1953 engines, 216 and 235 still had the dippers and no rod inserts, babbit applied directly to the rod. The 1953 Power Glide engine and all 1954 engiines had the babbit applied to the insert and full pressure oiling.

Thanks so much for the background info, especially Chevgene.I think I am going to give up golf and stick to my old Chevs, much better value for money and you don't get lonely when you miss the hole.

Gene
How can I tell if the set of main bearings I am about to install ( NORS ) needs line bored or not?

May say "precision bearing" on the box. Precision bearings have a somewhat shiney surface, bearings that are made to be line bored have just a dull gray surface.
Where are the bearings from? What brand?
And what year is the 216?
The 216 engine from 1948 and up were "born" with precision bearings. After 1948 the main bearings sold by Chevrolet and all major bearing companies for 1947 and prior engines were of the precision type, did not require line boring, and had to be replaced in complete sets. After a set was installed just one or two bearings could be then replaced.