Quote:
Originally Posted by Flathead
Herm, what is your opinion of the original thrust faces on the rear main, they always seem to be worn out and or broken.
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In My Opinion:
Ford Factory bearings never had problems, T's, A's, or B's, and including the Babbitted Ford V-8's. Even the ones that raced with stock motors, and overheads. Sure, if you abuse an engine, anything is possible.
My brother-in-law told me he bought a 1934 Sedan, that was in, 1946 from on a farm sale cheap, only bidder. I don't remember the miles, but a lot. Never had a wrench on it. He said the car ran very well, he drove it hard for 3 years, but always took care of his stuff. He said it was one of the fastest cars he ever owned, and was always dependable.
So what made that Babbitt last, and many of the new pours don't.
It always comes back to the peening. Some Guys do peen, but not good enough or correct. Either Babbitt to cold, Babbitt Jig not filled out. Shaft area peened, but thrust not peened. Shaft area peened to much, or hard, and the Babbitt will push the Babbitt away from the block even more, as it makes the shaft area longer then you have block.
Many Guys use Kwik-Way Align Bores. They are slow, but are as good of a Align Bore as you can buy. I used one that was New Old Stock, many years ago. and I think I had about 15 of them at one time. But, you have to set them up correctly. The two middle bar bearings have to have the right amount of tension from a spring compressed by a collar. It has been a lot of years, but I think you pushed the spring down 1/2 inch, and tightened a bolt by hand, to hold the tension. If you do not do this, you get bar sag, and a bad bore job, so this keeps everything straight.
So, if your Align Bore has sag in the middle, you are going to have a lot of whip in the middle bearing that will eat at the Babbitt, until it opens it self up more then you would like.
So, Mr. Flathead, what does this have to do with the rear thrust! Not a Dam thing, so I will get back to that. LOL
Many of new Babbitt jobs that went bad, was because of the lack of Peening, but the rest of the machine work was so bad, it would have went bad anyway. On these jobs, what was noticed, was way to much end play. I remember one as .040 thousandths, less then a 100 miles. Although I cant say which went first, but that much clearance would have been beating the heck out of it, and pumping oil out the rear main.
The worst thing you can do is set the main clearance to tight. What happens is the first .010 thousandths will be come plastic from the friction, it can't help its self, so it wiggles its self free. So the first .010 of Babbitt has lost a lot of its strength, and good wearing surface.
Thanks
Herm.
Here are some Babbitt jobs that went bad in a very short time, I saved the caps, from the Guys I have heard of. for show and tell.
All well known Babbitters.
The first picture is good old Fords.
The 3 in the 3rd row, I don't know how they keeping away with this kind of work.
Fourth row, first two pictures is what caps looks like when your heating the cap to pour with a cutting torch, burnt tin spots, Babbitt can't stick.