Tweet
I am looking for suggestions that may help me fix a problem. Last Summer, I started replacing the clutch, flywheel & pilot bushing on my '61. Turns out some previous "mechanic" center-punched the rim of the crankshaft to hold the pilot bushing in place. Removing it was a bear and had to be cut out. The crankshaft bore is distorted and I have tried grinding a little with the Dremel tool and then re-install a bushing. The bushing gets distorted and the input shaft will not enter the bushing. I gind a little more and repeat. I got frustrated and distracted and am now attempting this project again. I did 2 more bushings last night. Don't laugh, but I think I have now installed and pulled 9 bushings and I am having to swallow some pride to announce that fact publicly on this board. Am I looking at having to pull the engine and or crank and take it to a machine shop? Or is there a reamer that someone knows about that will replace the grind-a-little and pull-a-little and repeat method I have unsuccessfully using. By the way, the 5/8" tap worked great on removing the bushings. Well worth the money. You wouldn't believe how sore my arms and wrists were from using a slide hammer on the first 7 bushings. Last night I finally tore apart an old Muncie to use its input shaft to test fit the bushings. I was getting tired of pressing the T-10 up there each time. Thanks, Doug
-
-
Re: Pilot Bushing Help
install the bushing and the ream with 19/32 reamer
-
Re: Pilot Bushing Help
my response should say then ream not the ream. sorry
Comment
-
Re: Pilot Bushing Help
I wondered about reaming it after it was installed. I was a little concerned that it may not last as long. The pulled bushings all show stress cracks and I wonder if they may cause shorter bearing life. Then again maybe all bushings show these cracks when they are pulled. Thanks for the tip, I'll go hunting for a reamer.Comment
-
Re: Pilot Bushing Help
Being a machinist, I would have a competent shop set the new bushing up in a lathe, dial it in, and remove some mat'l. from the i.d. to obtain .007" to .009" of running clearance. (racing clearance!) Then while still in the lathe, bore a .002" lead (or overbore) on the leading edge of the bushing--the edge facing the trans. This will help the trans start in the bore. Now chamfer a .050" by 45 degree chamfer on that lead edge. That'll make sure you don't bung up the bore while trying to jam the trans in. As far as the flywheel goes, it should be rebored on the back end to receive a new oversize o.d. bushing to really do it right, but you might be able to get away with just the bushing modifications. I used to drag race a hot '57 and did'nt run a bushing just to get faster shifts, but being older and wiser (?) now, I really would'nt recommend it! Good luck! J.Comment
-
Re: Pilot Bushing Help
Are you shure that you have the right crank in the engine? I nearly tore my hair out on my '61 trying to get the pilot bushing to fit the crank, it turns out that the engine was swapped with one out of an automatic. Whoever did the last bearing replacement had ground down the bearing and then punched to keep from slipping. I'm told that you can buy a bearing that will fit auto crank to 4 speed input shaft. I learned this after working the bearing to fit.Tom BradyComment
-
Re: Pilot Bushing Help
i have never seen a chevy crankshaft that the pilot bushing hole was ever a different size.as far as i know all cranks have the same size hole within a couple of thousands. the parts books do not list a different crank for auto trans.
Comment
-
Re: Pilot Bushing Help
That's what really got me. Went to all the parts books and couldn't find a different part number for auto vs. manual crank or and different bushing listed for any thing even close to my small block. I know the hole in the crank is too small, I have no idea how it got that way but after I was done grinding the bushing to fit, I caught a thread on a different news group that mentioned the special bushing. May be all smoke. I was trying to verify and hoping someone here could confirm.Tom BradyComment
-
Re: Pilot Bushing Help
Auto and manual cranks are the same.Comment
Comment