Crank pulley bolt question
Thread Starter
Instructor
Joined: Jan 2011
Posts: 214
Likes: 0
From: Des Moines, Iowa
Crank pulley bolt question
I'm in the process of replacing my underdrive pulley with a stock one, and after taking out the bolt I found this:
Does just the lower part of the bolt that is darker actually thread into the crank, or does the upper yellowish part thread in also? There is a black chunk of something stuck pretty good to the bolt, and it's just past/outside the black part of the threads. I'm really hoping I didn't screw up the crank threads, could this be a combination of excess loctite and grease that hardened?
Anyone else ever have this issue or know what it could be? Any help is greatly appreciated!
Does just the lower part of the bolt that is darker actually thread into the crank, or does the upper yellowish part thread in also? There is a black chunk of something stuck pretty good to the bolt, and it's just past/outside the black part of the threads. I'm really hoping I didn't screw up the crank threads, could this be a combination of excess loctite and grease that hardened?
Anyone else ever have this issue or know what it could be? Any help is greatly appreciated!
Racer
Joined: Oct 2007
Posts: 263
Likes: 7
From: Brownsville Texas
I'm in the process of replacing my underdrive pulley with a stock one, and after taking out the bolt I found this:
Does just the lower part of the bolt that is darker actually thread into the crank, or does the upper yellowish part thread in also? There is a black chunk of something stuck pretty good to the bolt, and it's just past/outside the black part of the threads. I'm really hoping I didn't screw up the crank threads, could this be a combination of excess loctite and grease that hardened?
Anyone else ever have this issue or know what it could be? Any help is greatly appreciated!
Does just the lower part of the bolt that is darker actually thread into the crank, or does the upper yellowish part thread in also? There is a black chunk of something stuck pretty good to the bolt, and it's just past/outside the black part of the threads. I'm really hoping I didn't screw up the crank threads, could this be a combination of excess loctite and grease that hardened?
Anyone else ever have this issue or know what it could be? Any help is greatly appreciated!
Thread Starter
Instructor
Joined: Jan 2011
Posts: 214
Likes: 0
From: Des Moines, Iowa
Got the crank pulley off, what a PITA. I've never taken one off before, needed to get out the breaker bar to get enough torque on the puller, maybe I'm just weak.
I took a good look at the inside of the crank, and I found a bunch of little remnants of hardened goop, but the threads seem 100% intact still, which is a relief to say the least. I cleaned them out as best I could and will be running the bolt in and out a few times to clean up the remainder of what may still be in there.
This is an aftermarket crank and internals, not OEM stuff. I believe DRM installed the pulley, I'll have to give them a call to see what they use when installing it. I'll be ordering a new bolt to go in with the new OEM pulley.
I took a good look at the inside of the crank, and I found a bunch of little remnants of hardened goop, but the threads seem 100% intact still, which is a relief to say the least. I cleaned them out as best I could and will be running the bolt in and out a few times to clean up the remainder of what may still be in there.
This is an aftermarket crank and internals, not OEM stuff. I believe DRM installed the pulley, I'll have to give them a call to see what they use when installing it. I'll be ordering a new bolt to go in with the new OEM pulley.
Last edited by ashanson; Feb 24, 2012 at 01:10 AM.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
Got the crank pulley off, what a PITA. I've never taken one off before, needed to get out the breaker bar to get enough torque on the puller, maybe I'm just weak.
I took a good look at the inside of the crank, and I found a bunch of little remnants of hardened goop, but the threads seem 100% intact still, which is a relief to say the least. I cleaned them out as best I could and will be running the bolt in and out a few times to clean up the remainder of what may still be in there.
This is an aftermarket crank and internals, not OEM stuff. I believe DRM installed the pulley, I'll have to give them a call to see what they use when installing it. I'll be ordering a new bolt to go in with the new OEM pulley.
I took a good look at the inside of the crank, and I found a bunch of little remnants of hardened goop, but the threads seem 100% intact still, which is a relief to say the least. I cleaned them out as best I could and will be running the bolt in and out a few times to clean up the remainder of what may still be in there.
This is an aftermarket crank and internals, not OEM stuff. I believe DRM installed the pulley, I'll have to give them a call to see what they use when installing it. I'll be ordering a new bolt to go in with the new OEM pulley.
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Thread Starter
Instructor
Joined: Jan 2011
Posts: 214
Likes: 0
From: Des Moines, Iowa
I thought about going aftermarket, are the OEM ones that bad? I have a guy willing to trade me his brand new stock one plus $75 cash for my used SLP.
Maybe I shouldn't be such a cheap a$$ haha, after spending a few grand on the SC kit, what's another $400 for something like an Innovators West pulley. I thought about going with the 10 rib 10% overdrive in the for sale section. I don't need 10 ribs, but it would be nice if I ever step up to an 8 rib setup, one piece already out of the way. I also have a fairly big/high overlap cam, so I'm going to lose a pound or two of boost, the 10% overdrive could help make up for that.
Maybe I shouldn't be such a cheap a$$ haha, after spending a few grand on the SC kit, what's another $400 for something like an Innovators West pulley. I thought about going with the 10 rib 10% overdrive in the for sale section. I don't need 10 ribs, but it would be nice if I ever step up to an 8 rib setup, one piece already out of the way. I also have a fairly big/high overlap cam, so I'm going to lose a pound or two of boost, the 10% overdrive could help make up for that.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
I thought about going aftermarket, are the OEM ones that bad? I have a guy willing to trade me his brand new stock one plus $75 cash for my used SLP.
Maybe I shouldn't be such a cheap a$$ haha, after spending a few grand on the SC kit, what's another $400 for something like an Innovators West pulley. I thought about going with the 10 rib 10% overdrive in the for sale section. I don't need 10 ribs, but it would be nice if I ever step up to an 8 rib setup, one piece already out of the way. I also have a fairly big/high overlap cam, so I'm going to lose a pound or two of boost, the 10% overdrive could help make up for that.
Maybe I shouldn't be such a cheap a$$ haha, after spending a few grand on the SC kit, what's another $400 for something like an Innovators West pulley. I thought about going with the 10 rib 10% overdrive in the for sale section. I don't need 10 ribs, but it would be nice if I ever step up to an 8 rib setup, one piece already out of the way. I also have a fairly big/high overlap cam, so I'm going to lose a pound or two of boost, the 10% overdrive could help make up for that.
OEM is bad even for stock application due to the poor elastomer bonding material.
Track Junky
Joined: Jun 2007
Posts: 4,074
Likes: 36
From: Orlando Area
Tech Contributor
The dark part is the threads engaged in the crank, nothing else. The lighter part is the threads that were not engaged.
A new bolt is a must - do not reuse the old one except to seat the balancer back on.
A new bolt is a must - do not reuse the old one except to seat the balancer back on.
Le Mans Master
Joined: Jul 2005
Posts: 5,328
Likes: 405
This is a great idea right up to the point where the threads gall and you end up having to remove the engine to replace the crankshaft because you just ruined the threads. It doesn't happen often but it does happen...the previous owner of one of my 'Vettes did it but glued the bolt in so I could have the pleasure of dealing with it. 
A better idea is to get a harmonic damper installer...it costs a little extra initially but it could save you $$$ and headaches down the road. I made my own installer from all-thread, too easy and it was cheap.
A better idea is to get a harmonic damper installer...it costs a little extra initially but it could save you $$$ and headaches down the road. I made my own installer from all-thread, too easy and it was cheap.
Track Junky
Joined: Jun 2007
Posts: 4,074
Likes: 36
From: Orlando Area
Tech Contributor
This is a great idea right up to the point where the threads gall and you end up having to remove the engine to replace the crankshaft because you just ruined the threads. It doesn't happen often but it does happen...the previous owner of one of my 'Vettes did it but glued the bolt in so I could have the pleasure of dealing with it.
A better idea is to get a harmonic damper installer...it costs a little extra initially but it could save you $$$ and headaches down the road. I made my own installer from all-thread, too easy and it was cheap.
A better idea is to get a harmonic damper installer...it costs a little extra initially but it could save you $$$ and headaches down the road. I made my own installer from all-thread, too easy and it was cheap.
I thought I remember reading somewhere that using the old bolt was standard practice even with the dealership. I may be wrong though. I would say that as long as the threads appear damage free and clean you will be fine. Galling threads is very common in stainless and aluminum but not as common with carbon steel (it's been a long time since I have researched this though so I may be wrong again).
Take it for what it's worth - one data point that happened to work out for me.
Le Mans Master
Joined: Aug 2007
Posts: 6,473
Likes: 297
From: Orange Park FL
I have read a couple threads thru the years where someone stripped the first few threads in the crank tyring to use the old bolt. Just go to NAPA and get a little longer bolt and start and tighten down the pulley till you get to 150lbs or so, then back it out and insert your new bolt that is the shorter one and finish torquing it down.
I have been using and loaning out my longer NAPA bolt for years now.
I have been using and loaning out my longer NAPA bolt for years now.