Rear oil leak and knock

[newshirt]

Originally Posted by Tom Wesenberg

"In the old days, they babbitted the rod bearings for side thrust but then learned that it wasn't necessary."

What would contol the side play if they didn't have babbit on the sides of the rods? Without the side babbit that would leave a lot of distance for the rod to float back and forth.

Dan said there is no piston rod side play, not like they thought there would be. But as you can tell, I'm no expert, and probably perverted what he tried to tell me -- which is that the babbit can flake off the sides. (I saw several like that.) Sorry... just trying to get through the territory without getting scalped...

Don't worry; It won't be long until those caps are pulled.

[James Rogers]

Originally Posted by newshirt

Dan said there is no piston rod side play, not like they thought there would be. But as you can tell, I'm no expert, and probably perverted what he tried to tell me -- which is that the babbit can flake off the sides. (I saw several like that.) Sorry... just trying to get through the territory without getting scalped...

Don't worry; It won't be long until those caps are pulled.

I don't know what "Dan" is talking about? All the stock rods I use and all I have ever seen have the thrusts on the sides. If and when I ever start pouring my own rods I will make sure the thrusts are there. This is one of the "modern improvements" that cost owners and make more work and money for unscrupulous builders. If the thrust is broken and partly gone it means the job was never done correctly in the first place. If you don't think there is no movement side to side in the rods just look at the amount of room at each side of the wrist pin between the rod and the piston sides. The thrust is the only thing controlling this and the only way to do that without the babbitt is to weld the sides and machine them to the correct size. This would effectively create a steel thrust. I have seen this done and would not recommend it, the ones I have seen done this way have been failures from seizing and breaking the rod. Your motor, do as you please but, this is one way to empty your wallet in a hurry.

[pat in Santa Cruz]

Originally Posted by Ed in Maine

On my car, the engine builder crimped the end of the tube and then dropped a ball bearing down the tube before the tube was threaded on to the rear main bearing. This restricted the draining capability in an attempt to flood the rear main bearing with oil. All this did was make a big mess on my garage floor!

Ed

Ford made such an oil tube for grain trucks. When those trucks were lifted at the elevator to dump the grain, the ball was supposed to prevent backflow. It also prevented outflow, as you discovered.