Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Crank End Play

Thread Tools
 
Search this Thread
 
Old 04-19-2011, 04:24 PM
  #1  
11 Second Club
Thread Starter
iTrader: (7)
 
AznMuscle's Avatar
 
Join Date: Jan 2007
Location: Someplace Hot
Posts: 817
Likes: 0
Received 1 Like on 1 Post
Default Crank End Play

My car has been F'ing up lately, crank position issues. Not gonna bore you with everything, this thread from yellowbullet I found pretty much covers it, but this is the part I am concerned with.


Yes you can check it in the car. Take a pry bar and pry the crank as far as you can in one direction. Then put a dail indicator on the snout or the balancer whateever. The move the crank all the way in the opposite direction. The differnce from start to finish is the crankshaft thrust amount. If it was in exess of 7-9 thousanths I would be concrned.


We did this, and it visibly looked to play about 1/16". It was bad. New motor time?

This is the thread for reference.

http://www.yellowbullet.com/forum/sh...ad.php?t=92391
Old 04-19-2011, 09:38 PM
  #2  
TECH Senior Member
 
joecar's Avatar
 
Join Date: Apr 2002
Location: So.Cal.
Posts: 6,077
Likes: 0
Received 12 Likes on 10 Posts

Default

Do you have A4...?
Old 04-20-2011, 04:16 AM
  #3  
11 Second Club
Thread Starter
iTrader: (7)
 
AznMuscle's Avatar
 
Join Date: Jan 2007
Location: Someplace Hot
Posts: 817
Likes: 0
Received 1 Like on 1 Post
Default

I have a t56.
Old 04-20-2011, 09:15 AM
  #4  
FormerVendor
iTrader: (18)
 
Jon@Texas-Speed's Avatar
 
Join Date: Sep 2004
Location: Lubbock, TX
Posts: 3,043
Likes: 0
Received 2 Likes on 2 Posts
Default

You need to actually measure it and see what it actually is moving. You usually want to see .004-.007". Any larger isn't a good thing. I would say the absolute most would be .012" or so. There's only a certain window the crank sensor will pick up the reluctor as well. If you're really seeing 1/16" it's probably time to start saving your money.

Jon
Old 04-20-2011, 06:58 PM
  #5  
11 Second Club
Thread Starter
iTrader: (7)
 
AznMuscle's Avatar
 
Join Date: Jan 2007
Location: Someplace Hot
Posts: 817
Likes: 0
Received 1 Like on 1 Post
Default

The car does cut off and backfire at higher rpm. We tightened the crank pulley, and it was moving a lot. I am saving for a lq now. how safe is this to drive though?
Old 04-21-2011, 12:05 AM
  #6  
TECH Senior Member
iTrader: (96)
 
01ssreda4's Avatar
 
Join Date: Aug 2007
Location: Turnin' Wrenches Infractions: 005
Posts: 24,241
Likes: 0
Received 81 Likes on 72 Posts

Default

At 40 thousandths the crank is scraping the inside of the block. It literally cannot go more then .030 to .040 without direct metal to metal contact. At .040 my motor ran perfect with zero issues. The thrust bearing was absolutely trashed though. It was a matter of time before I had catastrophic failure. Here's the thread if you are interested. And you do need a dial indicator to get a correct measurement (with the drive belts off). Don't go crazy prying though. I found that mine (new engine) would basically rest in the rearward position and I only had to really pry behind the crank pulley forward to get my measurement.

https://ls1tech.com/forums/racers-lo...ew-engine.html



Quick Reply: Crank End Play



All times are GMT -5. The time now is 02:37 PM.