Railguy

I've been thinking about changing my auto trans to a manual.Than I happen to read Most Olds cranks aren't machined to accept the manual trans.I have two other cranks I looked and sure enough no pilot bearing hole. In other words if it came with an auto trans then a manual will not fit with out reworking the crank.Also very few Olds' had manual trans.Just wondered if every one was aware of this or if I was the only that didn't know! Or may I'm wrong.
railguy

2blu442

If you do a search you'll find a few threads discussing this. Last year I had an early 400 crank cut for a pilot bushing and it wasn't difficult for my machine shop to do it. The only downside is you need to pull the engine, then crank to have it done. John

Railguy

Wouldn't it be possible to machine an adapter that bolted to the fly wheel to house the pilot bushing.Than shorten the input shaft the appropriate amount with a new pilot shaft machined on.The machine shop could use the center of the fly wheel to make the adapter.As long as it stays out of the way of the pressure plate it should work.I mean if my engine was already out I would deffanitly rework the crank,but it seems simple for some one with that kind of ability.My mondello book has the measurements for the pilot hole in the crank so if you take those and figure in the position of the adaptor it should be easy to figure how much to take off the in put shaft.
railguy

2blu442

There is an aftermarket bearing made for cranks that are not drilled that requires cutting a piece of the input shaft off. Here's some old links for you to read through discussing this topic:

https://classicoldsmobile.com/forums...ans-crank.html

https://classicoldsmobile.com/forums...put-shaft.html

https://classicoldsmobile.com/forums...hine-shop.html


John

citcapp

You don't have to cut the shaft of the transmission when using the adapter bearing. You can hand drill the recess for the shaft with a 1/2" drill motor and a secession of drill bit sizes with cutting oil. Takes time but can be done

Railguy

You don't have to cut the shaft of the transmission when using the adapter bearing. You can hand drill the recess for the shaft with a 1/2" drill motor and a secession of drill bit sizes with cuttingoil. Takes time but can be done


I can't see how thats possible with a hand drill.The 2 spare cranks I have,have nothing just casting marks,absolutely no machining.
railguy

2blu442

That sounds like a better idea Pat. I do know a local guy who drilled one out that was still in the car. He must have done something along this line. John

Railguy, I'm thinking with a small drill bit start at the bottom of the hole and slowly drill your depth. Go with progressively larger drill bits until you have the diameter large enough. Yes, there is a risk if you get it off center you may make your crank out of balance.

MX442

Someone should write an article on this and make it a sticky.

Railguy

I know my limitations And believe me the hole would be more than a little off.On the light side how about this get a buddy to hold the engine at 5000RPM then crawl underneath and hold a drill bit with a pair of vice grips.My new nick name.......................Lefty!
railguy

2blu442

Yes, this is one of those common topics that come up on a regular basis.

John

DeltaPace77

I'm curious of this, as never knew it was a problem. Sold a guy the 403 engine out of my 77', which now resides under the hood of his 67' Cutlass post car with a 4 speed. Know he didn't pull the motor apart, so I'm gonna try finding out what he did.

citcapp

Sometimes you find a 455 with a drilled crank. The 455 John sold me came out of a Toro and it has a drilled crank so I didn't have to do a thing.

All of the cranks i have seen have a tampered hole just not deep enough. I believe Richard drilled out his crank maybe he can chime in. Others on this site have done it as well. I believe the only way to do do this with the engine out of the car. I just couldn't bring myself to cut the shaft on a transmission. Just my two cents

My442

I tried the adapter bearing method first. Steve Minore has a fixture that bolts to the flywheel. Using a huge drill motor and an expensive drill bit, I drilled out the back of the crank for clearance.

The crank is SUPER HARD, and it took ten minutes to go into the crank about 1/2". Hardest material I have ever worked on.

The adapter bearing in then put into the recess in the crank for the torque converter snout. I used a center punch, and made a series of raised dimples on the I.D. Then, I added some blue loc-tite to the O.D. of the bearing, and knocked in in with a 2 pound hammer and a suitable socket.

I used all GM parts for the conversion.

As soon as I started to drive the car, there was a problem: I could not shift into reverse. It would grind.

The reason was the conversion bearing was not concentric with the recess of the crank.

I still drove the car, and after about 500 miles, the conversion bearing started to squeal like a small pig.

Pulled the engine, and had the crank corrected drilled for the BCA7109 bearing.

Works perfectly now.

Railguy

Here are some pics of my crank it'a 350
IMG_3316.jpg

IMG_3317.jpg

IMG_3318.jpg

Railguy

I'm curious of this, as never knew it was a problem. Sold a guy the 403 engine out of my 77', which now resides under the hood of his 67' Cutlass post car with a 4 speed. Know he didn't pull the motor apart, so I'm gonna try finding out what he did.


My Mondello book said very few automatic engines where given the crank that could be used with a manual trans.So maybe yours was one of those.

When I rebuilt my motor I had My rotating assembly balanced no way am I going to drill it by eye ball.

Railguy

On a chevy isn't there just a bushing?Isn't the Chevy manual trans the exact same thing?And if it is,then is it possible that the 3/4" hole is there just so the same trans will work in both Brands?Also the bearing only works when the clutch is depressed.The hole thats 1.7"why couldn't you press bearing in to it?
railguy

DeltaPace77

Guy got back to me and used a bushing. He's a retired machinest with a lathe, and had to turn the bushing a bit to fit inside the 403 crank. Also, his car's actually a 70' F-85.

MX442

When I got my W-30, it had a 4-speed in it. However after decoding the #'s, and options, it was apparent that it was originally an auto car that was converted. So, is this a conversion bearing, or drilled the right way?

citcapp

Looks like a stock crank to me. Some autos came with the stick crank. Mine did. That is an aftermarket roller bearing though.

Indy_68_S

Looks like a real pilot bearing in the proper hole ....not the 'AT conversion' bearing which is larger dia. Also, another clue is the tip of your trans input shaft. These are typically cut/trimmed for the AT conversion bearing setup...

MX442

The trans that was in there was not trimmed. However the input shaft bearing was trashed and so was the cluster, 2nd, and reverse. Ended up selling all the 4speed stuff and building a th400 for it. Wish I kept it all and kept it a 4 speed. I was hung up on making it factory original again. Now I decided to put the original engine in storage, and throw a junkyard 455 in it to thrash. Wish I left it a 4 speed.