Pilot Bushing from Mars?

[Vette66AirCoupe]

Today I was all set to reinstall the clutch on my '60 283. I had already checked to make sure the pilot bushing fit the input shaft (thanks IH2LOSE). I had some help standing by and popped the pilot bushing out of the freezer and was kind of stunned when I couldn't get it started into the back of the crank. After quite a bit of hammering I stopped to take a look. Long story short, I miked the bushing and found it to be almost 1.1 inches while the hole in the crank was 1.06 inches across. Doesn't sound like much but believe me, this looks wrong. This sucker doesn't seem to be the right bushing. Off to the parts store where they produce the same size bushing as was provided in the clutch kit. The guy says his book says it's for a slew of small block Chevy's for years and years. Worse part, every stinkin' part I took off the car is there EXCEPT the old pilot bushing which I would love to be able to measure but the gremlins have hidden it. :W I stopped the project as I didn't want to damage anything forcing the wrong part though it seems like an impossible fit anyway. I'm wondering if I have an aftermarket crankshaft that takes a different bushing. :confused Anybody been up against this before? I'm thinking if worse comes to worse I could get a machine shop to turn this one down but I don't know what size to ask him to turn it down to. 1.065, 1.070, 1.075? I'd appreciate any light anyone can shed on this situation.

 

[bossvette]

You would want a .001 press fit if your hole is 1.060 turn the bushing to 1.061

Too much press and the ID will close up.

 

[allcoupedup]

I think I remember hearing crankshafts that were supplied on powerglide cars had a smaller bushing. Hope someone with more knowledge confirms this....
Brian

 

[wishuwerehere82]

Ditto on what Bossvette says.
http://www.atlasbronze.com/CAST_Bronze_Properties_2.pdf

 

[bossvette]

I thought autos had a different size hole but can't be sure, I remember making pilot bushings back in the 60's to do conversions but wasn't sure if it was on a Chevy or Buick my memory isn't what it used to be.

 

[allcoupedup]

http://www.chevytalk.com/tech/transmission/4speedconvo.html


extract:
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]NOTE: I bought a pilot bearing for a Chevrolet with manual trans (only one listed, one size fits all). It didn't fit in the end of the crank, outside diameter of the bearing was too large. Called around and visited several parts stores, all had the same part, all too large. I suppose the crankshaft for Powerglide cars are different from crankshafts for standard shift cars. Became a real headache. With no other solution, I ground down the pilot bearing (equally, I hope) on a grinder until it fit in the end of the crankshaft. I have since found that Year one, Inc. has a pilot bearing listed in their catalog that is for converting a Powerglide car to a manual trans.[/SIZE][/FONT]



I checked yearone and couldn't find anything. Doesn't mean they don't have it because their search function leaves much to be desired. I googled this and found that many other have had the same issue.

brian

 

[allcoupedup]

check this out --- sound familiar?

http://www.chevelles.com/forums/showthread.php?p=585589

 

[Vette66AirCoupe]

Thanks to all for enlightening me. Now if I can just find someone who sells it already cut to spec I can order it and not worry about getting the one I have now cut to the proper dimension. Since this problem seems to be well documented here on the internet somebody must be making them.

 

[67HEAVEN]

I froze mine in the freezer overnight.

 

[Vette66AirCoupe]

I froze mine in the freezer overnight.

Me too, but I've seen more shrinkage from jumping in a pool!

 

[00fxd]

There is an auto parts company out there called "Pioneer". They have a great many parts and pieces all usually available from your local auto parts store. Their clutch/flywheel/pilot bearing catalogue will surely show the adapting bushing you need. Have a look throught their performance parts catalogue too while your at it. You'll be amazed. Engine stud kits, sfi approved flex plates, roller rockers.

 

[Subfixer]

Hopefully VNV will post here... We ran into the same problem when we put the 5 speed in his small block 65. He ran to the parts store and came back with a bushing that was the correct size.

 

[cfalson]

You have a late 70's bushing, for 283/327's small journal cranks the pilot bushing is smaller. Go to you local FLAPS or speed shop and let them know you are looking for 283/327 from the the 60's and they will give you the correct one.

 

[Vette66AirCoupe]

You have a late 70's bushing, for 283/327's small journal cranks the pilot bushing is smaller. Go to you local FLAPS or speed shop and let them know you are looking for 283/327 from the the 60's and they will give you the correct one.

I did specify that it was from a '60 Corvette at three different parts stores and one speed shop. The old guy at the speed shop showed me a listing he had showing that the bushing I had in my hand was for small blocks from day one, including the 265 CI. If I'm understanding this correctly I'm not looking for a bushing made for an original 4 speed car but for one that will fit the smaller automatic car engine's crank while still fitting over the 4 speed input shaft. This doesn't sound like a part I'll find in a GM box.

 

[JL66REDCPE]

Hopefully VNV will post here... We ran into the same problem when we put the 5 speed in his small block 65. He ran to the parts store and came back with a bushing that was the correct size.

Terry - I was also present when we put the 5 speed in Mark's (VNV) car. Paul (Subfixer) is correct Mark learned that his small block was originally attached to a powerglide. As I remember he just went down to the local parts store (NAPA) and got one. Subfixer knows this first hand as he spent a lot of time under the car that day working on it.

 

[srthom13]

I installed a pilot bushing in my 66 BB - M 21 - last year. Went to a GM dealer and purchased a roller bearing type ( GM 14061685 ) . I wanted a bronze one but was told by them that the roller bearing type was now the only GM replacement. I did not measure it but it was a pefect fit ( without freezing ) for both the crank and trans. Maybe the roller bearing type will work for you. Steve

 

[Vette66AirCoupe]

John,

What time does Mark get up on Sunday's? I'm hoping he has the receipt with the part number on it. I visited two different NAPA stores yesterday to no avail.

Steve,

I saw one of those roller jobs yesterday but unfortunately it was also the larger size. I'd love to find that design in the size I need.

Brian,

A friend of mine has the Year One catalog, hard copy, and he couldn't find the conversion bushing listed. However, he did give me the specs for the "wrong" one (the proper one for a real 4 speed car). 1.094 OD and .592 ID, per the Year One catalog.

 

[00fxd]

You're better off with the bronze bushimg.

 

[JL66REDCPE]

Terry - I just got off the phone with Mark. He agreed on the powerglide pilot bearing being smaller. He was up to his ears putting new carpet etc in the 65 when I called him and he asked me to post this on his behalf. He said he did not have the part number. He verified that he just went out and got it at a local parts store. He used RTS (regional tire supply). He said you are probably not going to find it at an Advance or Autozone. He thought NAPA would probably have it. He said the parts store he went to was an old style parts store that "has everything".

 

[Vette66AirCoupe]

Thanks John. I might need a phone number for that place.

Terry