1911 Ford Model T Restoration: A long day at Mike Bender's shop

In a previous blog entry I mentioned that the engine block needed some repairs that required brazing. Properly doing that required the block to be preheated in an oven, which unfortunately melted the crankshaft bearings in the block.

Normally we think of bearings being made up of a series of steel balls or cylinders that allow a shaft to rotate freely. However, the Model T crankshaft, and many cars during the first few decades of automobiles, did not use a traditional bearing. Instead the bearing was a metal called Babbitt, made up of an alloy of mostly tin, copper and antimony. This material lined the surface of the block and bearing caps that come in contact with the three crankshaft journals of the Model T engine.

Putting new Babbitt bearings into a Model T block requires molds and the ability to carefully line bore the resulting bearings to ensure that the three bearings are in a straight line, and have a clearance of 0.002" with the crankshaft. 0.002" is a really small clearance; 1/500 of an inch!

There are only a few places in the U.S. that have the equipment and experience to do the job. Mike Bender in Tulsa, OK is one of those experts. Mike rebuilt the engine for our 1915 Model T runabout in 2019, and offered to repour and drill the bearings for the engine block for our 1911 car.

So in June of 2022, I made the three hour drive to Mike's shop to "help" Mike do the Babbitt work on the engine block. It was an enjoyable, but long day as Mike poured the new oversized crankshaft journals and then carefully line bored the journals for the desired clearance. The bearing journals were fine tuned by using a material called "Timesaver", which is an abrasive paste that is applied between the crankshaft and journals that finely cuts the Babbitt until there is a clearance of 0.002". Pretty cool stuff, and much quicker than the original method of scraping the bearings with a special knife to remove small amounts of material.

We finished up around dinner time, and drove home after a long but productive day. The block was now ready to go to a machine shop to have the cylinders bored for some oversized pistons and to have the valve seats reworked.