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Old 06-26-2012, 10:48 PM   #1
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Default Do I need a new crankshaft?

Just took off my crank pulley because it was wobbling.


Can I still use this crank or is it time for a new one? I'm guessing the crankshaft bolt wasn't properly torqued since I had to remove it a bunch of times recently.

I have a good pulley boss/pulley/woodruff key. But does the crank need to be replaced as well?

You can click pics for 3000x2000 res.


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Old 06-26-2012, 10:57 PM   #2
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The damage to the crank nose doesn't look all that horrible. I'd certainly attempt the
Loctite 660 Quick-Metal Loctite 660 Quick-Metal
repair first. Worst-case scenario is you wind up having to replace the crank anyway. Best-case is it lasts for another half light-second or more.
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Old 06-26-2012, 10:58 PM   #3
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i'd wait for someone else to chime in; take my opinion with a grain of salt...
but the crank looks fine.
a new pulley boss looks to be in order.
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Old 06-26-2012, 11:06 PM   #4
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Yeah I have a new everything except the crank. I even have a crank that I gave away to a friend.

I figure the same way - worst case scenario it starts wobbling again I'll just put in another crank.
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Old 06-27-2012, 12:14 AM   #5
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Reinstalled everything using my old 1.6 pulley boss. Once the thinner boss arrives (cause I need it for toothed wheel) I'll redo it. For now, no wobble.

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Old 06-27-2012, 01:46 AM   #6
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Crank is fine....I'd loctite it and be done. I recently did this and my crank was much worse than this and have had no problems since
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Old 06-27-2012, 01:55 AM   #7
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With loctite fix you basically loctite crank + key + timing belt sprocket into 1 solid piece, correct?
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Old 06-27-2012, 08:25 AM   #8
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Quote:
Originally Posted by soviet View Post
With loctite fix you basically loctite crank + key + timing belt sprocket into 1 solid piece, correct?
Yes basically fill in the key way on the crank with Loctite....set the woodruff key in ..and slide the crank gear/pulley over key. The excess loctite will fill in the gaps. note this is Loctite 660 aka quick metal...for me not the easiest stuff to find an cost about 15$ for small tube.
I also used regular blue Loctite on the crank bolt..torque to a little over 90ftlbs
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Old 06-27-2012, 09:52 AM   #9
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Quote:
Originally Posted by Joe Perez View Post
The damage to the crank nose doesn't look all that horrible. I'd certainly attempt the Loctite 660 Quick-Metal repair first. Worst-case scenario is you wind up having to replace the crank anyway. Best-case is it lasts for another half light-second or more.
I'd think he could get a full light-second out of it, the keyway might be a little loose at the end, but the keyway doesn't appear displaced at all, as shown in the m.net locticte repair how-to. A new pulley is definitely in order though.
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Old 06-27-2012, 10:15 AM   #10
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I posted in the other thread: crank good, pulley shot. JB Weld or the Loctite fix if you think the key is too loose. Otherwise, go for it.
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Old 06-27-2012, 05:38 PM   #11
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Quote:
Originally Posted by fooger03 View Post
I'd think he could get a full light-second out of it, the keyway might be a little loose at the end, but the keyway doesn't appear displaced at all, as shown in the m.net locticte repair how-to. A new pulley is definitely in order though.
You know what's funny, is that after I posted that, it sort of hit me that the speed of light is actually not all that fast.

I mean, it is fast. We all know that. Faster than a leopard, for instance, or a lotto vendor on welfare-check day. But it's not incomprehensibly fast. My own car has traveled just over 1.149 light-seconds in only 22 years, which easily falls into the range of "things that I can actually wrap my head around," especially since it was parked for the majority of that time.
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Old 06-27-2012, 06:56 PM   #12
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Damn, my chassis is right around 1 light second. The crank... was in 4 different cars at this point.
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Old 06-27-2012, 08:26 PM   #13
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I have two cranks you could have.
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Old 06-28-2012, 12:19 PM   #14
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My keyway is worse than yours with most of the damage toward the last 1/4 of the outter portion of the nose. I have over 100k on it with multiple teardowns and no Locktite, just torqued to factory specs, and it looks no worse now than it did 100k miles ago.
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Old 06-28-2012, 01:51 PM   #15
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Quote:
Originally Posted by Faeflora View Post
I have two cranks you could have.


Quote:
Originally Posted by jcnormar View Post
My keyway is worse than yours with most of the damage toward the last 1/4 of the outter portion of the nose. I have over 100k on it with multiple teardowns and no Locktite, just torqued to factory specs, and it looks no worse now than it did 100k miles ago.
100k miles turbo?
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Old 06-28-2012, 06:10 PM   #16
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Non turbo. Built 1.9L, lightened crank, 11:1 compression. Lots of autocrossing/high rpm before and after the re-build (100+ events). The last 30k+ the engine has seen numerous trips to 8000 rpm.

When I bought the engine, the damage had already been done. I bought a new pulley boss and key. The key fits snugly in the keyway.
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