Pilot shaft diameter

[circlepilot]

Question: The pilot shaft of my A833 is measuring .750, however I can insert a .825 (.075 difference) piece of bar stock in the pilot shaft hole in the crankshaft. The crank was originally used with a 904. I had the crankshaft register modified to accept a larger torque converter, (I was going to go back with a 904 set up but elected to go manual) the pilot hole for a manual transmission wasn't touched. This is a 1965 slant 6 build. Do I need a bushing? or am I reading too much into it. A bushing to reduce the pilot hole from .825 to .750 would be an awfully thin bushing.
Norm

 

[AJ/FormS]

Yes you need a bushing and up here NAPA stores carry it.
It's kindof an adapter bushing, as, to do this right, your crank would need to be drilled and resized to fit the factory bushing.
After the bushing is in, you kindof need to "degree the crank" to make sure the centerlines of the crank, and of the trans, are on the same line.

Having said that, Since you have already resized the convertor register, just go get a BB to fit both the crank and the input, do not install any bushing, and measure the depth in the back of the crank. Usually, but not always, when this swap is done, the trans input shaft will be too long, and a portion of it will need to be sawn off. But, you gotta leave enough to be supported by the BB.
Alternatively, you can just go to the Dodge truck dealer, and get the BB from an early Dakota, for same application. I got me one of those in 1999, and it's still going strong.

As you are doing this swap, maybe keep track of all the parts you had to get to make it work. guys are always asking.

Btw
you know that there is a different clutch pedal for the slanty clutch than for a V8 clutch right?

 

[Professor Fate]

Question: The pilot shaft of my A833 is measuring .750, however I can insert a .825 (.075 difference) piece of bar stock in the pilot shaft hole in the crankshaft. The crank was originally used with a 904. I had the crankshaft register modified to accept a larger torque converter, (I was going to go back with a 904 set up but elected to go manual) the pilot hole for a manual transmission wasn't touched. This is a 1965 slant 6 build. Do I need a bushing? or am I reading too much into it. A bushing to reduce the pilot hole from .825 to .750 would be an awfully thin bushing.
Norm

Many times the pilot bore is not finished to final size on engines that were originally equipped with an automatic transmission, and it sounds like yours isn't. A bushing like you describe would have a wall thickness of .0375- I doubt you would even be able to install it without deforming or distorting the bushing.
Since you have already had the crank pocket enlarged to later LA dimensions, I would do as AJ recommended and use the later Dakota bearing which installs into the convertor pocket.
More Information for TIMKEN FC69907
Confirm the depth of the pilot hole, though. Even though it won't be used for a bushing, it still needs to be deep enough to clear the transmission input shaft. It's easy enough to drill it a little deeper if needed, since it's no longer being used to center a bushing it becomes a non-critical dimension- you can even do it with a hand drill if you have an assembled motor. I've never been a fan of sawing off the input shaft, even though it's a relatively common quick fix.