The Stovebolt Site Forums The Shop Area Engine Shop 1948 216 Main bearing shims are too thick and too few-

Geez the books I have are calling for 4x .002" shims under each side of the main bearing caps to start off with. Then start the adjustment procedure... What I received from EGGE Machine and from everyone that I've contacted by phone they just send you one set of one thickness shims (too thick) I believe they are .006" and that's it. They DO NOT peel apart to make thinner ones. Does anyone have a source to purchase shims from that are closer to being correct? I can't be the only one that's dealt with this and there is no way that everyone just put this one size shim set on and called it good. Did you folks just make your own from .002" shim stock? Thank you all as always -freezerburn

I think I got mine from the Filling Station but I see Chevs of the 40s has them listed. Bearing Shims Mine looked like one piece .006" shims made by Federal Mogul. I sent one to Pre68dave and he managed to peel them. I then took a utility knife and scraped down at the corner and they peeled.

Try soaking one stack in a cap with Power Blaster.

After a while hold the stack by one end and slide the other end across a course file. Then look closely at the end, you will be able to separate them.

I don't know a lot about manufacturing but I would guess that the shims are stamped from a stack of sheets and thus they look and act like one piece.

I used a knife but a file might even work better.

Been there myself. Swore up and down and at those shims. They will seperate

if the main bores in the block are correct and the crankshaft is ground to the correct dimensions, you won't need shims. I could never figure out why you would need them. The block and crankshaft are (supposed to be anyway) held to +/- .0005" tolerance. Do the math from there. Although '48 is the pivotal year, '49 and beyond don't require them, at least Egge doesn't provide them with bearings sets after '48. My suspicion is the precision insert bearings weren't quite as precision in the era these engines were built, as they are today.

All 216's and 235's came from the factory with shims on the mains until mid 1955. At that point they also changed to bearings with tangs.

Well s**t I'm still swearing, lol.
I have a small butane soldering iron and if worst comes to worst I'll give that a whirl too.
I have a line on an nos set and will have to wait until Monday for the call.
I have to agree with 'Dave on the necessity of shims- especially if you want a good seal on the rear main.
Thanks folks I'll keep trying to separate what I have until Monday anyway ahaha
And of course I'll post up what works and how -freezerburn

just try it without the shims, you shouldn't need any, unless you have purposely ground the crankshaft too large. I really see no connection between shims and the crankshaft seal? Yes from the factory in original installations they did come with shims, but in present times, when you are replacing them with modern present day insert bearings, I don't see it. Except for the bit about it being a '48, for present day replacement bearing sets from Egge at least, up to '48 they provide shims, '49 and beyond they don't provide shims. That may just be Egge. I don't know what the criteria they are using for this discrepancy (difference?) Being that yours is a '48, I don't know? You can always just measure the ID, and the OD and subtract to get the difference, or simply set it in place, and being very careful, slowly tighten down the caps making sure the crank continues to turn freely , if it does, then you can use plastigage. Unless of course you are enjoying the battle with the shims.

Unless you have the crank ground special you still need shims on all the mid 1955 and earlier engines. At least all I have worked on.

I ended up using the .006" shims as templates and made a set out of .002" brass shim stock. Scissors for the perimeters and exacto knife for the bolt holes. Worked well. I started with the 4x shims per side of caps and ended up using 2x per to get .002" clearance. Adjusted as the book says 'by feel' then double checked with plastiguage at the end.
When I called around for shims all that were available or known had 10 pieces. Thanks and good luck folks, freezerburn