Crank/Harmonic balancer bolt

Thread Tools
 
Search this Thread
 
Old Mar 15, 2025 | 04:30 PM
  #1  
EsoWuhn's Avatar
Thread Starter
Registered User
 
Joined: Aug 2014
Posts: 107
From: southeast
Crank/Harmonic balancer bolt

Snapped the head off of one of the holts holding the crank pulley to the balancer. Would tapping/drilling it out be my best course of action? Anyone else have this happen to them? Stupid and my apologies, just want to make sure to do things as close to right as possible.
Old Mar 15, 2025 | 06:23 PM
  #2  
illumined's Avatar
1978 Ninety Eight
 
Joined: Jul 2014
Posts: 467
Having had several broken bolts I would say the best thing to start with would be an extractor, less likely to damage the threads. As a last resort you can take it to a machine shop and have them fix it.
Old Mar 15, 2025 | 09:13 PM
  #3  
Sugar Bear's Avatar
Registered User
 
Joined: Aug 2011
Posts: 4,120
Try grinding or filing the remaining bolt flat, strike it on center with a punch, apply penetrating oil and let it sit overnight. Strike it again and then drill it with a left hand/reverse drill bit. It may turn out with the drilling.

Take extra time to punch precisely on center and drill it on center/straight.
Old Mar 16, 2025 | 04:17 AM
  #4  
joe_padavano's Avatar
Old(s) Fart
 
Joined: Mar 2007
Posts: 50,815
From: Northern VA
Now that the head is broken off, is there any resistance to just spinning the stub out with a punch? Unless the bolt is cross-threaded or the threads are rusted, it should back out pretty easily.
Old Mar 16, 2025 | 06:03 AM
  #5  
oldolds88's Avatar
Registered User
 
Joined: May 2012
Posts: 1,503
From: laingsburg mi
drill it thru the backside, probably will unscrew itself
Old Mar 16, 2025 | 12:06 PM
  #6  
BillK's Avatar
Registered User
 
Joined: Dec 2016
Posts: 1,986
From: Beautiful Southern Maryland
Like Joe said it might come out by hand. Take the rest of the bolts off and take the pulley out of the way and give it a try.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
madmax442.com
Vintage Oldsmobiles
1
May 24, 2024 10:56 AM
Gene kerr
Big Blocks
2
Apr 1, 2020 08:07 AM
Oldsragger
Small Blocks
10
Jun 15, 2015 04:33 AM
455man
Small Blocks
3
Apr 29, 2011 06:32 AM
defiant1
Small Blocks
4
Apr 2, 2011 05:11 PM




All times are GMT -7. The time now is 05:02 PM.