Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by: KPower

Do I need a new crankshaft?

Thread Tools
 
Search this Thread
 
Old 06-26-2012, 09:48 PM
  #1  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
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.


soviet is offline  
Old 06-26-2012, 09:57 PM
  #2  
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,052
Total Cats: 6,615
Default

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.
Joe Perez is offline  
Old 06-26-2012, 09:58 PM
  #3  
Senior Member
iTrader: (8)
 
phillyb's Avatar
 
Join Date: Sep 2010
Location: misery
Posts: 1,127
Total Cats: 9
Default

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.
phillyb is offline  
Old 06-26-2012, 10:06 PM
  #4  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
Default

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.
soviet is offline  
Old 06-26-2012, 11:14 PM
  #5  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
Default

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.

Attached Thumbnails Do I need a new crankshaft?-dsc_0856.jpg  
soviet is offline  
Old 06-27-2012, 12:46 AM
  #6  
Junior Member
iTrader: (4)
 
1FastMx5's Avatar
 
Join Date: May 2011
Posts: 153
Total Cats: -40
Default

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
1FastMx5 is offline  
Old 06-27-2012, 12:55 AM
  #7  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
Default

With loctite fix you basically loctite crank + key + timing belt sprocket into 1 solid piece, correct?
soviet is offline  
Old 06-27-2012, 07:25 AM
  #8  
Junior Member
iTrader: (4)
 
1FastMx5's Avatar
 
Join Date: May 2011
Posts: 153
Total Cats: -40
Default

Originally Posted by soviet
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
1FastMx5 is offline  
Old 06-27-2012, 08:52 AM
  #9  
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,140
Total Cats: 229
Default

Originally Posted by Joe Perez
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.
fooger03 is offline  
Old 06-27-2012, 09:15 AM
  #10  
Elite Member
iTrader: (21)
 
rleete's Avatar
 
Join Date: Jun 2007
Location: Rochester, NY
Posts: 6,599
Total Cats: 1,263
Default

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.
rleete is offline  
Old 06-27-2012, 04:38 PM
  #11  
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,052
Total Cats: 6,615
Default

Originally Posted by fooger03
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.
Joe Perez is offline  
Old 06-27-2012, 05:56 PM
  #12  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
Default

Damn, my chassis is right around 1 light second. The crank... was in 4 different cars at this point.
soviet is offline  
Old 06-27-2012, 07:26 PM
  #13  
Elite Member
iTrader: (2)
 
Faeflora's Avatar
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,682
Total Cats: 130
Default

I have two cranks you could have.
Faeflora is offline  
Old 06-28-2012, 11:19 AM
  #14  
Newb
 
jcnormar's Avatar
 
Join Date: Jan 2009
Posts: 16
Total Cats: 0
Default

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.
jcnormar is offline  
Old 06-28-2012, 12:51 PM
  #15  
Elite Member
Thread Starter
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,493
Total Cats: 268
Default

Originally Posted by Faeflora
I have two cranks you could have.


Originally Posted by jcnormar
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?
soviet is offline  
Old 06-28-2012, 05:10 PM
  #16  
Newb
 
jcnormar's Avatar
 
Join Date: Jan 2009
Posts: 16
Total Cats: 0
Default

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.
jcnormar is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Cody Strife
Engine Performance
20
05-14-2017 01:27 PM
skou
WTB
4
10-11-2015 03:42 PM
Frank_and_Beans
WTB
1
01-15-2012 05:27 AM
ZX-Tex
Insert BS here
17
06-06-2010 07:39 AM



Quick Reply: Do I need a new crankshaft?



All times are GMT -4. The time now is 11:36 PM.