crank with no threads
Burning Brakes
Joined: Jun 2000
Posts: 865
Likes: 6
From: Auburn Michigan
Most SBC cranks did not have a threaded bolt on the end of the crankshaft snout until around the late 60's if I recall correctly. Does yours not have threads in it, or has a bolt been broken off in there? Might be able to see with a mirror & flashlight.
If it is an early crank, I am not sure if they took a different balancer, or how they were pressed on. Anyone?
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 37
Likes: 0
The balancer is an interference fit on the crankshaft snout, so it shouldn't wiggle.
Most SBC cranks did not have a threaded bolt on the end of the crankshaft snout until around the late 60's if I recall correctly. Does yours not have threads in it, or has a bolt been broken off in there? Might be able to see with a mirror & flashlight.
If it is an early crank, I am not sure if they took a different balancer, or how they were pressed on. Anyone?
Most SBC cranks did not have a threaded bolt on the end of the crankshaft snout until around the late 60's if I recall correctly. Does yours not have threads in it, or has a bolt been broken off in there? Might be able to see with a mirror & flashlight.
If it is an early crank, I am not sure if they took a different balancer, or how they were pressed on. Anyone?
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
I had a mid 60's 327 crank with no threads a while back. I successfully drilled and tapped it with the engine in the car. I seem to recall there was a forged opening that held the drill bit true.
Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 276
From: Melbourne, Victoria, Australia
Hi
Yes drill and tap the crankshaft, also use the correct tool to install the ballancer, It has a thread that screws into the crankshaft and has a wide nut to tighten the ballancer till its fully seated.
Then remove the threaded shaft with two nuts tightened.
I always clean the crankshaft and put a little oil on the crankshaft snout and ballancer. You can get away with a couple of longer bolts to start the ballancer onto the crankshaft, then when it is almost home use the correct length bolt and torque it. Do not overdo it if you think its not going any further and is jammed remove the ballancer put oil on check the crankshaft for any burs (going over a little with emery paper should make it fit easily) emery paper is like sandpaper but on a cloth.
If you are not careful you will end up having to tap an even bigger thread.
Yes drill and tap the crankshaft, also use the correct tool to install the ballancer, It has a thread that screws into the crankshaft and has a wide nut to tighten the ballancer till its fully seated.
Then remove the threaded shaft with two nuts tightened.
I always clean the crankshaft and put a little oil on the crankshaft snout and ballancer. You can get away with a couple of longer bolts to start the ballancer onto the crankshaft, then when it is almost home use the correct length bolt and torque it. Do not overdo it if you think its not going any further and is jammed remove the ballancer put oil on check the crankshaft for any burs (going over a little with emery paper should make it fit easily) emery paper is like sandpaper but on a cloth.
If you are not careful you will end up having to tap an even bigger thread.
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 37
Likes: 0
Hi
Yes drill and tap the crankshaft, also use the correct tool to install the ballancer, It has a thread that screws into the crankshaft and has a wide nut to tighten the ballancer till its fully seated.
Then remove the threaded shaft with two nuts tightened.
I always clean the crankshaft and put a little oil on the crankshaft snout and ballancer. You can get away with a couple of longer bolts to start the ballancer onto the crankshaft, then when it is almost home use the correct length bolt and torque it. Do not overdo it if you think its not going any further and is jammed remove the ballancer put oil on check the crankshaft for any burs (going over a little with emery paper should make it fit easily) emery paper is like sandpaper but on a cloth.
If you are not careful you will end up having to tap an even bigger thread.
Yes drill and tap the crankshaft, also use the correct tool to install the ballancer, It has a thread that screws into the crankshaft and has a wide nut to tighten the ballancer till its fully seated.
Then remove the threaded shaft with two nuts tightened.
I always clean the crankshaft and put a little oil on the crankshaft snout and ballancer. You can get away with a couple of longer bolts to start the ballancer onto the crankshaft, then when it is almost home use the correct length bolt and torque it. Do not overdo it if you think its not going any further and is jammed remove the ballancer put oil on check the crankshaft for any burs (going over a little with emery paper should make it fit easily) emery paper is like sandpaper but on a cloth.
If you are not careful you will end up having to tap an even bigger thread.
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 37
Likes: 0
mine slides on easy and with key in I can wiggle off w/o using puller upon further examination it looks the bolt broke off . that has to be the only way to stay on ...it can not be fitted otherwise I couldn't remove so easy..tpia have to get 90 deg drill and use easy out hopefully it works... car run fine before this.
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