Stray Bearing Shim
 

Oh Crap! Cleaning the block gasket surface so I can re-install the pan and I look on the floor under the engine and there is a connecting rod bearing shim lying on the floor!!! It just showed up! Now I have to figure out where it came from! It is .004" thickness and is in perfect shape. I have not done anything with the bearings. WTF!!!

Re: Stray Bearing Shim
 

If it fell out the rod nut should be loose,

Re: Stray Bearing Shim
 

Ditto this. Check the rod nuts. If they are all snug, then my guess is that whoever built your engine let a stray shim fall into the oil pan, and it's been there all along until you dropped the pan to clean it. If you find a loose rod cap, you know where to replace the the shim.

Re: Stray Bearing Shim
 

All the nuts seem to be tight with cotter pins installed very nicely. I guess I should remove the cotter pins and put a socket on the rod nuts to be sure.
What are the rod nut torque specs?

Re: Stray Bearing Shim
 

If one fell out check all four rod caps.One more reason why cotterpins were all they had,but not good for this application,they dont hold torque.

35 pounds..I would plastgage and reset all rod bearings

Re: Stray Bearing Shim
 

Sorry, wouldn't delete

Re: Stray Bearing Shim
 

Perhaps a "friend" put it there to confuse you.

Re: Stray Bearing Shim
 

I know a guy that would do just that! And then sit there and watch you check all your rod clearances.

I can't see a shim just "falling" out. If that is the case, what happens when the engine is running?

Re: Stray Bearing Shim
 

No one else has been around. That would be sorry!

Re: Stray Bearing Shim
 

The same guy who knocks on the engine block when you first start it...that guy

Re: Stray Bearing Shim
 

I would test the rods for loose side to side motion, If they are all the same I wouldn't disturb the rod nuts other than to check for 35# torque, unless it is time to check bearing clearances. That shim could have been stuck on the pan flange or block surface after the last time the bearings were tightened, or as a joke that some people might play.

Re: Stray Bearing Shim
 

I really don't see any way a shim could fall out but I am going to check things out just to be sure.

Re: Stray Bearing Shim
 

Working on a fiends Model T , the #4 rod cap was not seated but was torqued tight. It had a slight knock. Reset it and lightly tapped all rod caps for the same sound. T runs great.
Good Luck

Re: Stray Bearing Shim
 

I'd check the tension on all of the big end bolts. Any loose one would be the culprit (if there is one). Once you have done that, try turning the engine over with the crank handle. If a shim has fallen out, that big end would be so tight after tightening it that you would not be able to turn the crank.

Re: Stray Bearing Shim
 

Re: Stray Bearing Shim
 

all the shims i used had a hole drilled in them so they would slide down over the bolt! no way they could come out

Re: Stray Bearing Shim
 

When you picked up the shim, was it oily or dry?

Re: Stray Bearing Shim
 

Not sure but it seems like it was dry.

Re: Stray Bearing Shim
 

Different from what I have experienced in that the shims I have seen were slotted for the cap bolt.

John

Re: Stray Bearing Shim
 

Can you post a picture of the shim