Originally Posted by Kohnke Rebabbitting
Ford used 86-7-7, in his Model T's, A's, and Model B's. If any one has lead in there motor, it has been replaced. During the war, the government had most of the Tin, so bearing builders had to use lead.
If Plastigage does not work for you, its not being used correctly.
Just about all Bearing Manufactures in the U.S. used Grade No.11, Grade 2, and Fords are all right, But Fords is dirty to machine, because of the amount of Antimony used.
Ford said, a 1 inch square of there Babbitt compressed to 14,000 pounds, would only compress, 2%, and that is way over what is needed. The proper clearance for a Model A shaft is .001-60 to not over .002-10
When a bearing has been adjusted down .006 thousandths, it is about time for new Babbitt any way, as the time gears are closer, and after you scrape, is even worse. The rear main will leak more, as the clearance up and down may be right, but the sides will always be standard, or what ever the hole size was when the new Babbitt was put in.
I built 3 engines for a Howard Kittleson in Mn. in the 80's some time. Two Model t's, and one Model A. His 1927 T Roadster went on the AK. tour. There is a lot to tell, but I will make it as short as I can. When he got back, he had 18,000 miles on it and wanted the main and rods checked. I pulled a.001 shim out of each rod, and stuck the engine, so I had to put them back. Done the same with the mains. He run the car wide open all the time. I told him to use 30 Wt., but he said he used 10-30 Wt., What could I say, NOTHING.
If you have Babbitt that is wearing, better check, and see why. The shaft should not be touching the shaft, it should be setting on oil molecule.
I have a few pictures of failed main cap, and showing what happened. I will put the first set on of what a original Ford Babbitt job looks like. The failed caps are of builders, we all know, and love.
Herm.
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