It's time to drill a pilot shaft hole in the forged crank from my 67 330. Engine is out of the car, runs good with no leaks so I do not want to remove the crank. What kind of bit did you guys use, I have a heavy duty 1/2 inch drill and lots of 3 in 1 oil. Thanks.

 

The shaft rides in a bearing not the crank itself. This is something for a machine shop. You'll have to remove the crankshaft.
Doing it your way will only friction weld the two together.

 

I understand what you are saying, I am only drilling for clearance on the end of the pilot shaft, I don't want to chop off the end of the shaft. Thanks

 

You have to have a hole drilled in the crank, then install a bearing into that hole which is where the tranny shaft will fit into. Machine shop.

 

Phone around .. you can find a shop that'll drill it without taking the crank out.

 

Start small and work your way up to a bit slightly larger that input shaft on trans. Its tough drilling but can be done. yes you are only drilling for clearance not for the bearing or adapter bushing.

 

Obviously you must already have a bearing/bushing that will fit the existing counter bore in the end of the crankshaft... If so, as long as that bearing supports a portion of the pilot shaft to prevent it from wobbling, the necessary clearance can be drilled in almost any manner... However, I would remove as little material as possible since you are attempting to do it by hand, and in the off chance you will want to have it redone by a shop...

 

The nose of the shaft is .590" on a Muncie. Something bigger like 5/8" or 11/16" would work.

 

You must insure that the hole that is drilled is perfectly on center and parallel to the crank. You stand the chance of a terrible rattle in the shifter as well as potentially destroying the bearings in the transmission if it is mis-drilled.

 

Thanks, I read a previous post where a Dorman 690-023 bushing would work well with the pilot shaft. I was planning to use a 11/16 bit and I was wondering what brand of bit you guys thought would work the best? Thanks again.

 

Does your block have the BOSS for Z bar pivot???

Johnny

 

You can do what you want however you will surely end up with an off center hole, that will also be out of round and not suitable for locating a bearing. This is not a hand held operation. The drill bit will walk. Never use a drill bit to open a prior drilled hole because a drill bit needs to be touching at the center of the work. My opinion after Forty years of cutting tools application speaking. Good luck.
Wayne

 

Yes the block has the boss for Z bar. Thanks for the advice Wayne.

 

i used a 3/4 bit i think..i gotta look at it..cant remeber..but believe it was 3/4...i got the engine up on a table and took my time i used a 1/2 drill as slow as it would go, and it drilled like butter...theres a divit to start the bit..i didnt start with anything smaller..i made sure it was level and centered..and no issues..


it was around 3/8 inch deeper, that i needed...so i felt good about it...i mocked it 5 or 6 times, and used clay to make sure after the drill..i wanted 1/8 inch more than i needed, for heat growth etc....and its strictly clearance..car is together and driving with no issues or worries, and i dont even think about it anymore unless i read something like this

i read all over the net how hard the crank was etc, and it was really soft..really soft..id never do it with the engine in the car...no way...

i used a brand new bit i bought off the snap on tool truck...no harbor freight stuff...worked for me..i felt i had enough experience to tackle the job and know how to use a drill...i bought a drill at a yard sale..it takes 2 people to hold it..lol...its quite the monster and came from an iron worker....but has a variable switch/built in rheostat and can turn really slow..some oil and it pushed like butter..worked for me...id do it again...its a totally stock low mile smogger 455 that never spins high....

 

Just to up date, I used a titanium (sp) 5/8 bit from Home Depot and drilled 3/4 inch deep hole with no problem at all. Lots of WD 40 and slow speed. Thanks to everone.