MTFCA Forum

Hey guys, I wanted to replace my pan gasket as it was leaking in a few spots. I figured since I was under there, I may as well pull the connecting rod caps and check the bearing surfaces. I know what Good looks like, problem is, I have no clue if what I'm looking at is Ok or No good. What do you guys think? Is it worth pulling main caps to look at those?

Here are the journal pics.

Were there any shims when you took them off?

Looks one cap looks good to me but the rest of this seems rather sad. If it was mine, it would be coming apart and getting freshened up. Time to mic the crank to ensure the journals as straight and round. If the crank is good and if there were shims, it might be possible to use TimeSaver to clean up the surfaces I guess it depends a bit on how much you really expect out of the car. An occasional run for coffee or ice cream requires a lot less than real touring. Somewhere the budget may have an impact as well.

There were shims on most of the bolts.

Looks like you made a good decision to check the bearings. The second picture shows the babbitt is worn thru to the steel cap. So that rod needs to come out and be rebabbited or exchanged for one of the correct diameter. I would look at the babbitt on the upper half of the rod bearings as well. The newer good looking cap doesn't appear to have a chamfer at the inside edges to catch and hold oil...
I agree with walber on measuring the crank journals and at least freshening up the engine bearings... so you can be confident driving it. You have a little work ahead of you before the summer driving season. Bill

John, I would not pull the main caps at this time, you have seen what you need to see. The rod bearings look tired and it is probably a good indication of the overall health of the engine. If it were mine, I would pull the engine and go through it top to bottom. In earlier times some people kept their model T's running with sawdust in rear ends, rice in the radiator, and leather belts as replacement for rod babbit, although that may work for a time, I would not recommend it. Continued use in its current condition will likely make your crankshaft unserviceable.

I disagree your rods look nearly new.
Your second picture shoes an oversized rod fit tight on an undersized journal heat caused the smear.
All of your pictures Indicate the same to me.
Give me a call 319 331 828five.

What is that blue on the shaft? Unless you were using prussian blue to determine the wear pattern that would be an indication of heat. Heat would occur if the bearing were too tight and/or there was not enough oil. Did the engine knock before you opened it up? If it were mine, I would look at side of the bearing in the rod, and if it looks as bad as the caps, I would for sure replace the babbit. If the upper side looks good, and the crank is not out of round, I might experiment with scraping the caps and re-fitting them. If any steel is exposed on the caps, I would re babbit them for sure.
Norm

Top three caps shot. Tin Babbitt.

Bottom cap, Rod, is lead babbitt, must have been replaced by it's self, one time.

The shaft Blue looks like Prussian Blue to me, that was not taken off when fitting. If the shaft got that hot to turn it Blue, all the rods would have melted out.

Normally, the babbitt melts out, and doesn't effect the color of the shaft.

Herm.

Is it just me, or does the second crank journal photo seem to show a crack running diagonally across the journal surface?