No shims in my connecting rods

50Trucking

Member
Bought a 30 2door sedan and dropped the pan to clean it out and inspect the bearings before running it. I was surprised that there are no shims in the connecting rods. The rods look good but no shims. Has anyone ran into this and what do you do to tighten the rods. I am using plastiguage and the first one is in specs.
 
As some may have pointed out already. No shims typically end of life is near for that rod or main cap. If it specs out ok then there is more life in the part in question. Personally if is already apart I would fix it before moving on.
 
The caps can be 'filed' using any very flat plate, glass works well. Put a sheet of 220 or so emery paper on the glass, then move the cap over it in a figure 8 pattern, this insures the cap will remain flat.
 
Hello, my 31 is in the same condition, when you have the rods off the crankshaft, check the diameter of the journals and surfaces.Not too unusual have crankshaft reground, causing oversized bearings.
 
Rod are smaller surfaces. Therefor, the rule of thumb is that the rods wear about twice as fast as the mains. Since you are at this critical stage; 1) oil changes are important, even if you drive only a few hundred miles per season, 2) excessive speed for long periods of time is hard on babbit. If you drive the car around town on errands you will be able to go a long time on what you have.
 
Rod are smaller surfaces. Therefor, the rule of thumb is that the rods wear about twice as fast as the mains. Since you are at this critical stage; 1) oil changes are important, even if you drive only a few hundred miles per season, 2) excessive speed for long periods of time is hard on babbit. If you drive the car around town on errands you will be able to go a long time on what you have.

I have found that the mains wear faster than the rod bearings. One of my engines has about 65,000 hard miles on it and I've replaced the main bearing inserts once but not the rod bearings. Maybe Ford made the rod journals smaller because he could and they don't wear as fast.
 
The stores that sell granite counter tops usually have small pieces left over that they will give you. You can glue emery paper to them and use them to take some material off your bearing caps. If you go too far you can add some shims. This is a one way street and when you eventually have the engine re Babbetted, you will have to replace the caps.
 
A problem with “no shims” is the bearing can only take about .006” shim removal, and then it becomes egg shaped. Easy to see if rods are out of the car, not sure how to tell if still in?
 
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